International Society of Sports Nutrition position stand: diets for body weight reduction

In the paper

“The critical issue with BMI is that it correlates poorly with body fat percentage (BF%) [13–15].”

What the sources say

• Supported

  In “BMI as a Determinant of Body Fat Mass,” the review explicitly describes a relatively poor correlation between BMI and percent body fat, citing evidence from men and the NHANES III database. It notes that the limitation is particularly pronounced in men. (LLM, conf=0.94)

  cites [13] Nuttall FQ. Body mass index: obesity, BMI, and health: a critical review. Nutr Today. 2015; 50(3): 117– 128. doi: 10.1097/NT.0000000000000092 PMC4890841 27340299 source
• Disputed

  The Discussion says BMI and percentage body fat were highly correlated within sex-age groups, contrary to the claim that they correlate poorly. The Results report BMI–body-fat correlations of 0.716–0.789 in men and 0.724–0.839 in women for the age groups specified. (LLM, conf=0.90)

  Checked by a reasoning model — may be wrong.

  cites [14] Flegal KM, Shepherd JA, Looker AC, et al. Comparisons of percentage body fat, body mass index, waist circumference, and waist-stature ratio in adults. AJCN. 2009; 89(2): 500– 508. doi: 10.3945/ajcn.2008.26847 PMC2647766 19116329 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [15] Okorodudu DO, Jumean MF, Montori VM, et al. Diagnostic performance of body mass index to identify obesity as defined by body adiposity: a systematic review and meta-analysis. Int J Obes (Lond). 2010; 34(5): 791– 799. doi: 10.1038/ijo.2010.5 20125098 source

In the paper

“Gout was the only one of the fifteen adverse effects for which men exhibited a higher prevalence.”

What the sources say

• Disputed

  In Results, Table 3, gout was more prevalent in men (0.8%) than women (0.0%), but it was not the only adverse effect with a higher reported prevalence in men. Sore throat (0.6% vs 0.4%) and dizziness (2.4% vs 1.8%) were also higher in men, although those differences were not marked statistically significant. (LLM, conf=0.93)

  Checked by a reasoning model — may be wrong.

  cites [49] Christensen P, Meinert Larsen T, Westerterp-Plantenga M, et al. Men and women respond differently to rapid weight loss: metabolic outcomes of a multi-centre intervention study after a low-energy diet in 2500 overweight, individuals with pre-diabetes (PREVIEW). Diabetes Obes Metab. 2018; 20(12): 2840– 2851. doi: 10.1111/dom.13466 PMC6282840 30088336 sourceExperimental — accuracy not yet measured

In the paper

“It is worth noting that traditional concerns with high protein intakes (i.e. adverse effects on kidney, liver, and bone health) lack evidentiary support in healthy populations [123–128].”

What the sources say

• Partly supported

  The Discussion reports no harmful effects on renal or hepatic function in resistance-trained young men consuming a high-protein diet, supporting the kidney and liver portions of the claim. The Methods describe blood tests but no assessment of bone health, and the Limitations caution that the small study may not apply to other populations. This paper therefore does not establish the broader claim for healthy populations or its bone-health component. (LLM, conf=0.88)

  cites [123] Antonio J, Ellerbroek A, Silver T, et al. A high protein diet has no harmful effects: a one-year crossover study in resistance-trained males. J Nutr Metab. 2016; 2016: 9104792. doi: 10.1155/2016/9104792 PMC5078648 27807480 sourceExperimental — accuracy not yet measured
• Partly supported

  The Background reports evidence that a high-protein diet for one year had no negative effect on kidney or liver function. The Conclusion reports no harm to bone density or content in exercise-trained women and states that there is no evidence of harm to bone health. These passages support the general concern being questioned, but the kidney and liver evidence is limited to a one-year study and this paper’s bone findings are limited to exercise-trained women, rather than healthy populations generally. (LLM, conf=0.85)

  cites [124] Antonio J, Ellerbroek A, Evans C, et al. High protein consumption in trained women: bad to the bone?. J Int Soc Sports Nutr. 2018; 15: 6. doi: 10.1186/s12970-018-0210-6 PMC5793405 29434529 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [125] French SJ, Kanter M, Maki KC, et al. The harms of high protein intake: conjectured, postulated, claimed, and presumed, but shown? AJCN. 2025; 122(1): 9– 16. doi: 10.1016/j.ajcnut.2025.05.002 40339907 source
• Partly supported

  The Introduction says no causal link between increased protein intake and kidney damage has been established in healthy people, and the Discussion says there is no evidence linking high-protein intake to kidney disease in healthy individuals. The paper does not establish the same point for liver or bone health; references to studies of calcium and bone outcomes do not substantiate that broader claim. (LLM, conf=0.88)

  cites [126] Devries MC, Sithamparapillai A, Brimble KS, et al. Changes in kidney function do not differ between healthy adults consuming Higher- compared with Lower- or normal-protein diets: a systematic review and meta-analysis. J Nutr. 2018; 148(11): 1760– 1775. doi: 10.1093/jn/nxy197 PMC6236074 30383278 sourceExperimental — accuracy not yet measured
• Disputed

  The Discussion (Diet characteristics; page unavailable) says high-protein diets can induce metabolic acidosis and increase urinary calcium, which may adversely affect bone metabolism. The Conclusions (page unavailable) also caution that excessive protein intake could lead to negative health outcomes. Although the study did not establish kidney, liver, or bone damage in healthy populations, it does not support the blanket assertion that these concerns lack evidentiary support. (LLM, conf=0.82)

  Checked by a reasoning model — may be wrong.

  cites [127] Kim H, Lee S, Choue R. Metabolic responses to high protein diet in Korean elite bodybuilders with high-intensity resistance exercise. J Int Soc Sports Nutr. 2011; 8: 10. doi: 10.1186/1550-2783-8-10 PMC3142197 21722409 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [128] Antonio J. High-protein diets in trained individuals. Res Sports Med. 2019; 27(2): 195– 203. doi: 10.1080/15438627.2018.1523167 30244609 source

In the paper

“However, this idea lacks support from controlled, isocaloric, protein-equated diet comparisons of disparate carbohydrate‒fat proportions, which consistently show no statistically significant fat loss differences between the KD and LFD groups [104,135,148,160,161].”

What the sources say

• Partly supported

  The Ketogenic diets section (page unavailable) says that, with scant exception, controlled protein- and energy-matched comparisons found no fat-loss advantage for ketogenic diets. It does not establish the more specific claim that every KD-versus-low-fat comparison showed no statistically significant difference; its summary includes non-KD comparators and notes a slight fat-loss advantage for higher-carbohydrate, lower-fat diets. (LLM, conf=0.86)

  cites [104] Aragon AA, Schoenfeld BJ, Wildman R, et al. International society of sports nutrition position stand: diets and body composition. J Int Soc Sports Nutr. 2017; 14: 16. doi: 10.1186/s12970-017-0174-y PMC5470183 28630601 sourceExperimental — accuracy not yet measured
• Partly supported

  The Conclusions report no significant difference in 12-month weight change, and Table 3 shows no significant between-group difference in body-fat percentage. But this trial compared healthy low-carbohydrate and low-fat diets, not a ketogenic diet and a low-fat diet under controlled, isocaloric, protein-equated conditions. The Results report different protein intakes, and the Weight Loss Intervention section says no calorie target was prescribed. (LLM, conf=0.90)

  cites [135] Gardner CD, Trepanowski JF, Del Gobbo LC, et al. Effect of low-fat vs low-carbohydrate diet on 12-Month weight loss in overweight adults and the association with genotype pattern or insulin secretion: the DIETFITS randomized clinical trial. J Am Med Assoc. 2018; 319(7): 667– 679. doi: 10.1001/jama.2018.0245 PMC5839290 29466592 sourceExperimental — accuracy not yet measured
• Not checked yet

  A check is scheduled.

  cites [148] Leaf A, Rothschild JA, Sharpe TM, et al. International society of sports nutrition position stand: ketogenic diets. J Int Soc Sports Nutr. 2024; 21(1): 2368167. doi: 10.1080/15502783.2024.2368167 PMC11212571 38934469 source
• Disputed

  In “Influence of Dietary Macronutrients on Energy Balance and Body Composition,” the paper reports a statistically significant pooled difference in body-fat loss favoring lower-fat diets (16 g/day; P < .0001), contrary to the claim that the comparisons consistently found no statistically significant difference. The authors consider the effect physiologically meaningless, but that does not make it statistically nonsignificant. (LLM, conf=0.90)

  Checked by a reasoning model — may be wrong.

  cites [160] Hall KD, Guo J. Obesity energetics: body weight regulation and the effects of diet composition. Gastroenterology. 2017; 152(7): 1718– 1727 e3. doi: 10.1053/j.gastro.2017.01.052 PMC5568065 28193517 sourceExperimental — accuracy not yet measured
• Not checked yet

  A check is scheduled.

  cites [161] Buga A, Kackley ML, Crabtree CD, et al. The effects of a 6-Week controlled, hypocaloric ketogenic diet, with and without exogenous ketone salts, on body composition responses. Front Nutr. 2021; 8: 618520. doi: 10.3389/fnut.2021.618520 PMC8044842 33869263 source

In the paper

“Hall and Guo [160] conducted a meta-analysis of 32 controlled feeding studies, strictly limited to comparisons where protein and energy intake were equated between conditions. No statistically significant differences in weight loss or fat loss were detected, despite carbohydrate proportions ranging 1%–83% and dietary fat ranging 4%–84%.”

What the sources say

• Disputed

  The ‘Influence of Dietary Macronutrients’ section confirms the 32 controlled feeding studies, equal protein and calories, and the stated carbohydrate and fat ranges. But it reports a statistically significant difference in body fat loss favoring lower-fat diets (16 g/day; P < .0001), contrary to the claim that no significant fat-loss difference was detected. The reported effect was described as physiologically small; the passage does not report a pooled weight-loss result. (LLM, conf=0.90)

  Checked by a reasoning model — may be wrong.

  cites [160] Hall KD, Guo J. Obesity energetics: body weight regulation and the effects of diet composition. Gastroenterology. 2017; 152(7): 1718– 1727 e3. doi: 10.1053/j.gastro.2017.01.052 PMC5568065 28193517 sourceExperimental — accuracy not yet measured

In the paper

“However, ADF tended to promote greater weight loss than CER and TRE.”

What the sources say

• Supported

  The Abstract’s Study Importance section says the pooled network analysis ranked alternate-day fasting highest for weight-loss efficacy, followed by caloric energy restriction and time-restricted eating. The claim’s “tended to” wording is consistent with that ranking. (LLM, conf=0.93)

  cites [67] Elortegui Pascual P, Rolands MR, Eldridge AL, et al. A meta-analysis comparing the effectiveness of alternate day fasting, the 5:2 diet, and time-restricted eating for weight loss. Obesity (Silver Spring). 2023; 31 (Suppl 1): 9– 21. doi: 10.1002/oby.23568 PMC10098946 36349432 source

In the paper

“However, these benefits are likely the result of weight loss via hypoenergetic conditions, rather than inherent or independent effects of intermittent energy restriction [61].”

What the sources say

• Supported

  Section 7 (page unavailable) says the available human evidence suggests intermittent fasting offers little to no cardiometabolic advantage over continuous energy restriction. It concludes that the magnitude of weight loss, rather than the dietary treatment, appears to be the main driver of the observed changes, supporting the claim’s qualified wording. (LLM, conf=0.90)

  cites [61] Rynders CA, Thomas EA, Zaman A, et al. Effectiveness of intermittent fasting and time-restricted feeding compared to continuous energy restriction for weight loss. Nutrients. 2019; 11(10): 2442. doi: 10.3390/nu11102442 PMC6836017 31614992 source

In the paper

“High-quality weight loss has distinct advantages for athletic performance.”

What the sources say

• Partly supported

  The Discussion and Conclusions (pages not provided) link lower body-fat percentage and higher fat-free mass with better field-test performance in youth soccer players and recommend aiming for optimal body composition. They do not test weight loss or establish that “high-quality weight loss” improves athletic performance; the study reports associations, not benefits caused by losing weight. (LLM, conf=0.86)

  cites [10] Esco MR, Fedewa MV, Cicone ZS, et al. Field-based performance tests are related to body fat percentage and fat-free mass, but not body mass index, in youth soccer players. Sports (Basel). 2018; 6(4): 105. doi: 10.3390/sports6040105 PMC6316319 30261675 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [11] Jalilvand F, Banoocy NK, Rumpf MC, et al. Relationship between body mass, peak power, and power-to-body mass ratio on sprint velocity and momentum in high-school football players. J Strength Cond Res. 2019; 33(7): 1871– 1877. doi: 10.1519/JSC.0000000000002808 30124563 source

In the paper

“A 25% lean mass loss as a result of VLEDs and LEDs is commonly reported [32–34].”

What the sources say

• Supported

  In “Composition, Safety, and Beneficial Effects” (page not supplied), the paper says lean body mass accounts for approximately 25% of total weight lost with very-low-calorie diets and describes its preservation as comparable to that with low-calorie diets. The 25% refers to a share of total weight loss, not a 25% reduction in a person’s starting lean mass; the paper also excludes the first two weeks of dieting from that approximate ratio. (LLM, conf=0.87)

  cites [32] Saris WH. Very-low-calorie diets and sustained weight loss. Obes Res. 2001; 9(Suppl 4): 295S– 301S. doi: 10.1038/oby.2001.134 11707557 source
• Partly supported

  In ‘An Introduction to Very-Low-Energy Diets,’ the review says that approximately 25% of total weight loss with LEDs is lean body mass; Table 1 also lists 25% lean body mass loss for VLEDs as a share of weight lost. The citing sentence omits that denominator and could be read as a 25% reduction in lean mass itself, which the source does not establish. (LLM, conf=0.86)

  cites [33] Ardavani A, Aziz H, Smith K, et al. The effects of very low energy diets and low energy diets with exercise training on skeletal muscle mass: a narrative review. Adv Ther. 2021; 38(1): 149– 163. doi: 10.1007/s12325-020-01562-0 PMC7854408 33211298 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [34] Hoie LH, Bruusgaard D, Thom E. Reduction of body mass and change in body composition on a very low calorie diet. Int J Obes Relat Metab Disord. 1993; 17(1): 17– 20. 8383636

In the paper

“Finally, of relevance to the present subtopic of non-VLED/LED research are the findings of Unick et al. [43,57], showing that faster initial weight loss is a predictor of long-term weight loss maintenance.”

What the sources say

• Supported

  The Discussion states that weight loss in the first two months predicted weight loss eight years later. The Results further show that participants with greater early weight loss had higher odds of achieving at least 5% weight loss at Year 8. This supports the citing sentence’s paraphrase of faster initial loss predicting long-term maintenance. (LLM, conf=0.92)

  cites [43] Unick JL, Neiberg RH, Hogan PE, et al. Weight change in the first 2 months of a lifestyle intervention predicts weight changes 8 years later. Obesity (Silver Spring). 2015; 23(7): 1353– 1356. doi: 10.1002/oby.21112 PMC4481874 26110890 source
• Supported

  The section “Early weight loss or program adherence as a marker of success” (page not provided) reports that greater weight loss in the first few months is associated with better long-term outcomes. It also states that weight loss in the first month predicted weight loss at 1, 4, and 8 years, supporting the claim about long-term maintenance. (LLM, conf=0.90)

  cites [57] Unick JL, Pellegrini CA, Demos KE, et al. Initial weight loss response as an indicator for providing early rescue efforts to improve long-term treatment outcomes. Curr Diab Rep. 2017; 17(9): 69. doi: 10.1007/s11892-017-0904-1 PMC5789799 28726155 source

In the paper

“Women also had a higher prevalence of adverse effects than men during and immediately after the trial, including constipation, diarrhea, nausea, dizziness, headache, infection, and hair loss.”

What the sources say

• Partly supported

  The Results (Table 3; page not specified) report more adverse effects overall in women than men during and immediately after the weight-loss period. Several listed effects were more prevalent in women, but dizziness was more prevalent in men (2.4% versus 1.8%); the table also groups nausea with other gastrointestinal symptoms rather than reporting it separately. These findings concern the initial weight-loss period, not the full PREVIEW trial. (LLM, conf=0.93)

  cites [49] Christensen P, Meinert Larsen T, Westerterp-Plantenga M, et al. Men and women respond differently to rapid weight loss: metabolic outcomes of a multi-centre intervention study after a low-energy diet in 2500 overweight, individuals with pre-diabetes (PREVIEW). Diabetes Obes Metab. 2018; 20(12): 2840– 2851. doi: 10.1111/dom.13466 PMC6282840 30088336 sourceExperimental — accuracy not yet measured

In the paper

“A consequence of low-quality weight loss called “collateral fattening” is the physiological drive to recover from lean tissue losses, which amplifies appetite, hyperphagia, and ultimately a rebound in body fat (i.e. “fat overshooting” [8,9].”

What the sources say

• Supported

  In “From a historical perspective” (page not provided), the paper says that lean-tissue deficits drive compensatory hyperphagia and that continued overeating to restore lean mass deposits excess body fat, producing collateral fattening and fat overshoot. This supports the claimed sequence following weight loss involving lean-tissue loss. (LLM, conf=0.92)

  cites [8] Dulloo AG, Miles-Chan JL, Schutz Y. Collateral fattening in body composition autoregulation: its determinants and significance for obesity predisposition. Eur J Clin Nutr. 2018; 72(5): 657– 664. doi: 10.1038/s41430-018-0138-6 PMC5945583 29559726 source
• ?Not checked — no full text of the sourcecites [9] Dulloo AG, Jacquet J, Montani JP, et al. How dieting makes the lean fatter: from a perspective of body composition autoregulation through adipostats and proteinstats awaiting discovery. Obes Rev. 2015; 16(Suppl 1): 25– 35. doi: 10.1111/obr.12253 25614201 source

In the paper

“Wang et al. [69] conducted an overview of systematic reviews and meta-analyses (upon which further meta-analysis was conducted), and found no statistically significant differences between ADF and TWF on fat mass or lean mass compared to CER.”

What the sources say

• Supported

  The Results (section 3.4.4) report that neither alternate-day fasting (ADF) nor the 5:2 diet differed from continuous energy restriction (CER) in effects on fat mass or fat-free mass in subgroup analyses. The Methods (section 2.3.2) define the 5:2 diet as fasting or reduced intake on two days per week. These are separate comparisons with CER, not a direct comparison of ADF with twice-weekly fasting. (LLM, conf=0.91)

  cites [69] Wang J, Wang F, Chen H, et al. Comparison of the effects of intermittent energy restriction and continuous energy restriction among adults with overweight or obesity: an overview of systematic reviews and meta-analyses. Nutrients. 2022; 14(11): 2315. doi: 10.3390/nu14112315 PMC9183159 35684119 source

In the paper

“In subjects with obesity, more rapid initial weight loss has been associated with greater long-term weight loss [41–43]”

What the sources say

• Supported

  The Introduction states that more rapid initial weight loss has been associated with greater long-term weight loss in obese patients. The Discussion also reports that participants who lost weight faster maintained greater losses at 18 months. Page numbers are not available in the supplied copy. (LLM, conf=0.94)

  cites [41] Nackers LM, Ross KM, Perri MG. The association between rate of initial weight loss and long-term success in obesity treatment: does slow and steady win the race? Int J Behav Med. 2010; 17(3): 161– 167. doi: 10.1007/s12529-010-9092-y PMC3780395 20443094 source
• ?Not checked — no full text of the sourcecites [42] Purcell K, Sumithran P, Prendergast LA, et al. The effect of rate of weight loss on long-term weight management: a randomised controlled trial. Lancet Diabetes Endocrinol. 2014; 2(12): 954– 962. doi: 10.1016/S2213-8587(14)70200-1 25459211 source
• Supported

  The Discussion reports that weight loss in the first two months was positively associated with weight loss eight years later among participants who were overweight or obese and had type 2 diabetes. The Results likewise show higher odds of achieving at least 5% weight loss at Year 8 for those with greater initial weight loss. The claim appropriately describes an association, though this study's participants also had type 2 diabetes. (LLM, conf=0.91)

  cites [43] Unick JL, Neiberg RH, Hogan PE, et al. Weight change in the first 2 months of a lifestyle intervention predicts weight changes 8 years later. Obesity (Silver Spring). 2015; 23(7): 1353– 1356. doi: 10.1002/oby.21112 PMC4481874 26110890 source

In the paper

“weight regain after VLED cessation is a concern, ranging from 2–14 kg in post-intervention periods ranging from 8 days to 5 years [33].”

What the sources say

• Supported

  The ‘An Introduction to Very-Low-Energy Diets’ section states that weight regain after VLED cessation ranged from 2 to 14 kg over post-intervention assessment periods of 8 days to 5 years. The review reports this finding from its authors’ previous systematic review; the citing sentence does not claim it was an original result of this paper. (LLM, conf=0.95)

  cites [33] Ardavani A, Aziz H, Smith K, et al. The effects of very low energy diets and low energy diets with exercise training on skeletal muscle mass: a narrative review. Adv Ther. 2021; 38(1): 149– 163. doi: 10.1007/s12325-020-01562-0 PMC7854408 33211298 source

In the paper

“Serious adverse effects of VLEDs (including sudden death precipitated by cardiac arrhythmias) were more prevalent in earlier research [33,46].”

What the sources say

• Supported

  The “Safety Profile of VLEDs” section reports a high incidence of sudden death following early VLEDs, attributed to cardiac arrhythmias. It contrasts this with later studies and a recent review reporting no major adverse events or cardiac arrhythmias. (LLM, conf=0.92)

  cites [33] Ardavani A, Aziz H, Smith K, et al. The effects of very low energy diets and low energy diets with exercise training on skeletal muscle mass: a narrative review. Adv Ther. 2021; 38(1): 149– 163. doi: 10.1007/s12325-020-01562-0 PMC7854408 33211298 source
• ?Not checked — no full text of the sourcecites [46] Ahmed W, Flynn MA, Alpert MA. Cardiovascular complications of weight reduction diets. Am J Med Sci. 2001; 321(4): 280– 284. doi: 10.1097/00000441-200104000-00007 11307868 source

In the paper

“The most common complaints are constipation, fatigue/muscle weakness, headache, and dizziness [30].”

What the sources say

• Supported

  The “Adverse events and attrition” section identifies constipation, fatigue/muscle weakness, headache, and dizziness as the most common complaints during total diet replacement. It reports these complaints in the PREVIEW study and says the same side effects occurred in the DROPLET trial. (LLM, conf=0.94)

  cites [30] Brown A, Leeds AR. Very low-energy and low-energy formula diets: effects on weight loss, obesity co-morbidities and type 2 diabetes remission – an update on the evidence for their use in clinical practice. Nutr Bull. 2019; 44(1): 7– 24. doi: 10.1111/nbu.12372 source

In the paper

“Jeppesen et al. [50] reported that short-term severe low energy availability was associated with adverse endocrine, metabolic, and skeletal-muscle adaptations and impaired exercise performance.”

What the sources say

• Supported

  The Physiological Consequences section describes adverse endocrine and skeletal-muscle responses, while the Abstract reports reduced resting metabolic rate and impaired exercise performance. The review focuses primarily on female athletes, as the Abstract specifies. (LLM, conf=0.92)

  cites [50] Jeppesen JS, Hellsten Y, Melin AK, et al. Short-term severe low energy availability in athletes: molecular mechanisms, endocrine responses, and performance Outcomes-A narrative review. Scand J Med Sci Sports. 2025; 35(6): e70089. doi: 10.1111/sms.70089 PMC12180388 40539747 source

In the paper

“In studies extending beyond 6 months, there were no statistically significant differences in body weight, body composition, and markers of cardiometabolic health (i.e. blood lipid profile, blood pressure, and glucose metabolism) between the IF and CER.”

What the sources say

• Partly supported

  The Results report no statistically significant differences beyond six months in body weight (§3.3), body composition (§3.4), blood pressure, or lipid profiles (§3.5). However, §3.6 reports a statistically significant reduction in long-term fasting glucose favoring fasting, so the blanket claim about glucose metabolism is not supported. (LLM, conf=0.92)

  cites [62] Siles-Guerrero V, Romero-Marquez JM, Garcia-Perez RN, et al. Is fasting superior to continuous caloric restriction for weight loss and metabolic outcomes in obese adults? A systematic review and meta-analysis of randomized clinical trials. Nutrients. 2024; 16(20): 3533. doi: 10.3390/nu16203533 PMC11510157 39458528 sourceExperimental — accuracy not yet measured

In the paper

“reiterating the conclusion that weight loss per se may be more important than the type of diet for the beneficial effects of IF.”

What the sources say

• Supported

  The Discussion states nearly the same conclusion: weight loss may matter more than diet type for the beneficial effects of intermittent energy restriction. The paper specifically makes this point about cardiometabolic risk markers. (LLM, conf=0.91)

  cites [63] Schroor MM, Joris PJ, Plat J, et al. Effects of intermittent energy restriction compared with those of continuous energy restriction on body composition and cardiometabolic risk markers - A systematic review and meta-analysis of randomized controlled trials in adults. Adv Nutr. 2024; 15(1): 100130. doi: 10.1016/j.advnut.2023.10.003 PMC10831889 37827491 source

In the paper

“In contrast to these findings, Arciero et al. [4,70,71] have shown superior body composition (reduced total body, fat, and visceral fat mass) with TWF compared with CER.”

What the sources say

• Partly supported

  The Results report greater losses of body weight and total, abdominal, and visceral fat mass with intermittent fasting–protein pacing than with continuous caloric restriction. But the intervention was a single 36–60-hour modified fasting period each week alongside higher protein intake, not twice-weekly fasting alone; the comparison does not isolate fasting from protein pacing. (LLM, conf=0.85)

  cites [4] Mohr AE, Sweazea KL, Bowes DA, et al. Gut microbiome remodeling and metabolomic profile improves in response to protein pacing with intermittent fasting versus continuous caloric restriction. Nat Commun. 2024; 15(1): 4155. doi: 10.1038/s41467-024-48355-5 PMC11133430 38806467 sourceExperimental — accuracy not yet measured
• Partly supported

  Results §5.3 reports reductions in body weight, total body fat, and visceral adipose tissue during the weight-loss phase. But Dietary Intervention §3.1 specifies one fasting day per week, not two, and that phase had no continuous-energy-restriction comparator. The later comparison was a modified regimen against a heart-healthy diet (§3.2; Results §5.8), not twice-weekly fasting against continuous energy restriction. (LLM, conf=0.90)

  cites [70] Arciero PJ, Edmonds R, He F, et al. Protein-pacing caloric-restriction enhances body composition similarly in obese men and women during weight loss and sustains efficacy during long-term weight maintenance. Nutrients. 2016; 8(8): 476. doi: 10.3390/nu8080476 PMC4997389 27483317 sourceExperimental — accuracy not yet measured
• Partly supported

  The Results (BW and composition during WL; page not provided) report greater reductions in body weight, total fat, and visceral fat for intermittent fasting plus protein pacing than for daily caloric restriction. But the Methods (Experimental design; page not provided) say only a subgroup fasted twice weekly during the first four weeks; from week 5, all fasting participants fasted once weekly. The reported overall comparison therefore does not establish the claimed result for twice-weekly fasting throughout. (LLM, conf=0.90)

  cites [71] Arciero PJ, Poe M, Mohr AE, et al. Intermittent fasting and protein pacing are superior to caloric restriction for weight and visceral fat loss. Obesity (Silver Spring). 2023; 31 (Suppl 1): 139– 149. doi: 10.1002/oby.23660 PMC10107279 36575144 sourceExperimental — accuracy not yet measured

In the paper

“It is notable that collectively, ADF [75] and TWF [76] trials resulted in a mean reduction of ~2 kg of lean mass at the 12-week point.”

What the sources say

• Supported

  Table 2 (Subgroup Analysis; page unavailable) reports a 12-week ADF lean-mass mean difference of −2.35 kg, consistent with an approximately 2 kg reduction. This source supports the ADF portion of the sentence; the separately cited TWF portion is not attributed to it. (LLM, conf=0.92)

  cites [75] Cui Y, Cai T, Zhou Z, et al. Health effects of alternate-day fasting in adults: a systematic review and meta-analysis. Front Nutr. 2020; 7: 586036. doi: 10.3389/fnut.2020.586036 PMC7732631 33330587 source
• Partly supported

  Results §3.7.4 (page unavailable) reports reduced fat-free mass in 5:2 (twice-weekly fasting) studies. Its initial pooled estimate was −2.17, but the estimate after excluding one trial was −1.24; the passage does not establish a 12-week endpoint. The paper does not provide a collective estimate for alternate-day and twice-weekly fasting trials. (LLM, conf=0.88)

  cites [76] Wu C, Chen B, Yu J, et al. Effect of the 5:2 diet on weight loss and cardiovascular disease risk factors in overweight and/or obesity: a systematic review and meta-analysis. Int J Endocrinol. 2025; 2025: 6658512. doi: 10.1155/ije/6658512 PMC11876533 40041761 sourceExperimental — accuracy not yet measured

In the paper

“These findings were echoed in another recent systematic review and meta-analysis by Schroor et al. [63] involving 28 RCTs that examined the effects of ADF, TRE, and TWF. Collectively, these IF variants were not superior to CER for improving anthropometric and cardiometabolic outcomes, reiterating the conclusion that weight loss per se may be more important than the type of diet for the beneficial”

What the sources say

• Supported

  The Results (Study characteristics; page unavailable) identify 28 RCTs covering TRE, ADF, and the 5:2 diet, which the Introduction describes as restricting intake on two days each week. The Discussion (page unavailable) concludes that the regimens combined were not superior to continuous energy restriction for weight loss, body fat, and other fasting cardiometabolic risk markers, while noting some outcome-specific differences. (LLM, conf=0.93)

  cites [63] Schroor MM, Joris PJ, Plat J, et al. Effects of intermittent energy restriction compared with those of continuous energy restriction on body composition and cardiometabolic risk markers - A systematic review and meta-analysis of randomized controlled trials in adults. Adv Nutr. 2024; 15(1): 100130. doi: 10.1016/j.advnut.2023.10.003 PMC10831889 37827491 source

In the paper

“Overall, the IF regimens resulted in similar weight loss to that of the CER.”

What the sources say

• Supported

  The Results section (‘Meta-analysis of IF regimens for weight loss’; page unavailable) explicitly reports similar weight loss for intermittent fasting regimens and continuous energy restriction, with no statistically significant overall difference. (LLM, conf=0.95)

  cites [67] Elortegui Pascual P, Rolands MR, Eldridge AL, et al. A meta-analysis comparing the effectiveness of alternate day fasting, the 5:2 diet, and time-restricted eating for weight loss. Obesity (Silver Spring). 2023; 31 (Suppl 1): 9– 21. doi: 10.1002/oby.23568 PMC10098946 36349432 source

In the paper

“The majority of ADF trials involve “fasting” days that consist of approximately 25% of the individual’s maintenance caloric requirements (~500 kcal), and are thus labeled modified ADF [58].”

What the sources say

• Supported

  Section 2.1, “Alternate-Day Fasting,” states that modified ADF permits 25% of maintenance needs—approximately 500 kcal—on fasting days and is the predominant type of ADF in the literature. This supports the claim about the majority of ADF trials. (LLM, conf=0.95)

  cites [58] Aragon AA, Schoenfeld BJ. Does timing matter? A narrative review of intermittent fasting variants and their effects on bodyweight and body composition. Nutrients. 2022; 14(23): 5022. doi: 10.3390/nu14235022 PMC9736182 36501050 source

In the paper

“For the goal of weight loss, it is axiomatic that hypoenergetic (negative energy balance; caloric deficit) conditions must be sustained [22,23].”

What the sources say

• Supported

  The “Energy Balance: Definitions” section states that when energy expenditure exceeds intake, negative energy balance results in loss of body mass. The “Treatment Versus Prevention” section also describes producing sustained reductions in body weight as requiring substantial, permanent behavior change. Together, these support the claim about sustaining a deficit to lose weight. (LLM, conf=0.91)

  cites [22] Hill JO, Wyatt HR, Peters JC. Energy balance and obesity. Circulation. 2012; 126(1): 126– 132. doi: 10.1161/CIRCULATIONAHA.111.087213 PMC3401553 22753534 source
• ?Not checked — no full text of the sourcecites [23] Strasser B, Spreitzer A, Haber P. Fat loss depends on energy deficit only, independently of the method for weight loss. Ann Nutr Metab. 2007; 51(5): 428– 432. doi: 10.1159/000111162 18025815 source

In the paper

“Pasiakos et al. [85] reported a 19% decrease in MPS during 10 days of moderate caloric deficit (20% below maintenance).”

What the sources say

• Supported

  The Abstract reports that mixed-muscle fractional synthetic rate fell approximately 19% during a 10-day energy-deficient phase at about 80% of estimated energy requirements, compared with weight maintenance. The Discussion likewise describes a 19% decrease after a 10-day moderate energy deficit. (LLM, conf=0.95)

  cites [85] Pasiakos SM, Vislocky LM, Carbone JW, et al. Acute energy deprivation affects skeletal muscle protein synthesis and associated intracellular signaling proteins in physically active adults. J Nutr. 2010; 140(4): 745– 751. doi: 10.3945/jn.109.118372 20164371 source

In the paper

“Along these lines, Arciero et al. [89,90] have repeatedly demonstrated that a high daily protein intake (>1.4 g/kg) consumed across 4–6 meals per day outperforms control diets of lower protein and meal frequency for fat mass reduction and lean mass preservation in hypocaloric conditions.”

What the sources say

• ?Not checked — no full text of the sourcecites [89] Arciero PJ, Ormsbee MJ, Gentile CL, et al. Increased protein intake and meal frequency reduces abdominal fat during energy balance and energy deficit. Obesity (Silver Spring). 2013; 21(7): 1357– 1366. doi: 10.1002/oby.20296 23703835 source
• Partly supported

  The Introduction (page unavailable) reports that a diet providing >1.4 g/kg/day across five to six meals produced greater improvements in body composition than a lower-protein, three-meal diet, including during an energy deficit. But that is a report of an earlier study: this paper’s own intervention was not energy-restricted and compared two high-protein groups, not a lower-protein control. Its results therefore do not establish the claimed repeated superiority for fat reduction and lean-mass preservation under hypocaloric conditions. (LLM, conf=0.86)

  cites [90] Arciero PJ, Edmonds RC, Bunsawat K, et al. Protein-pacing from food or supplementation improves physical performance in overweight men and women: the PRISE 2 study. Nutrients. 2016; 8(5): 288. doi: 10.3390/nu8050288 PMC4882701 27187451 sourceExperimental — accuracy not yet measured

In the paper

“In chronic interventions, higher-protein conditions consistently outperform lower-protein comparators for weight loss-related outcomes.”

What the sources say

• Partly supported

  Section 3.3 (page not available in our copy) reports small pooled advantages for higher-protein diets in weight loss and fat-mass loss. But BMI and waist-circumference differences were not statistically significant, and the weight-regain result weakened when an influential trial was removed. The claim that higher-protein conditions consistently outperform across weight-loss-related outcomes overstates the findings. (LLM, conf=0.90)

  cites [97] Vogtschmidt YD, Raben A, Faber I, et al. Is protein the forgotten ingredient: effects of higher compared to lower protein diets on cardiometabolic risk factors. A systematic review and meta-analysis of randomised controlled trials. Atherosclerosis. 2021; 328: 124– 135. doi: 10.1016/j.atherosclerosis.2021.05.011 34120735 sourceExperimental — accuracy not yet measured

In the paper

“These intriguing effects of very high protein intakes are not anomalous; Antonio et al. [121–124] conducted several other trials that consistently showed non-adipogenic effects in resistance trainees assigned additional energy intake (~400–800 kcal) when consumed as protein (2.7–4.4 g/kg).”

What the sources say

• Partly supported

  The Discussion reports that resistance-trained participants consumed about 800 additional kcal per day, averaged 4.4 g/kg/day of protein, and did not gain fat mass. This paper supports one trial at the upper end of the cited ranges, not the claim about several trials. The Discussion also says carbohydrate intake was not controlled, so it does not establish that all additional energy was consumed as protein. (LLM, conf=0.85)

  cites [121] Antonio J, Peacock CA, Ellerbroek A, et al. The effects of consuming a high protein diet (4.4 g/kg/d) on body composition in resistance-trained individuals. J Int Soc Sports Nutr. 2014; 11: 19. doi: 10.1186/1550-2783-11-19 PMC4022420 24834017 sourceExperimental — accuracy not yet measured
• Partly supported

  The Discussion (page unavailable) reports that subjects consumed approximately 400 additional calories daily during the high-protein phase, with no significant change in fat mass; it also describes similar findings from two earlier trials. Results > Diet (page unavailable) gives 3.3 g/kg/day for this trial, and the Discussion gives 3.4 and 4.4 g/kg/day for the earlier trials. This copy does not establish the full stated ranges of 400–800 kcal and 2.7–4.4 g/kg/day across the cited trials. (LLM, conf=0.84)

  cites [122] Antonio J, Ellerbroek A, Silver T, et al. The effects of a high protein diet on indices of health and body composition--a crossover trial in resistance-trained men. J Int Soc Sports Nutr. 2016; 13: 3. doi: 10.1186/s12970-016-0114-2 PMC4715299 26778925 sourceExperimental — accuracy not yet measured
• Partly supported

  The Abstract and Results report that resistance-trained men consumed more protein and calories during the high-protein phase without gaining fat mass. The Discussion also describes a prior trial with about 400 additional kcal/day and a loss of fat mass. This paper does not establish the full 400–800 kcal/day or 2.7–4.4 g/kg ranges attributed collectively to the cited trials; its own high-protein phase averaged 3.32 g/kg/day. (LLM, conf=0.86)

  cites [123] Antonio J, Ellerbroek A, Silver T, et al. A high protein diet has no harmful effects: a one-year crossover study in resistance-trained males. J Nutr Metab. 2016; 2016: 9104792. doi: 10.1155/2016/9104792 PMC5078648 27807480 sourceExperimental — accuracy not yet measured
• Partly supported

  The Discussion (page unavailable) reports that the high-protein group consumed more calories without a change in fat mass, supporting the non-adipogenic finding. But this paper reports one trial in exercise-trained women, not several trials exclusively in resistance trainees; its reported energy-intake difference was about 226 kcal, not 400–800 kcal, and its mean protein intake was 2.8 g/kg/day. The Discussion cites other investigations but does not establish the full range claimed for this source. (LLM, conf=0.88)

  cites [124] Antonio J, Ellerbroek A, Evans C, et al. High protein consumption in trained women: bad to the bone?. J Int Soc Sports Nutr. 2018; 15: 6. doi: 10.1186/s12970-018-0210-6 PMC5793405 29434529 sourceExperimental — accuracy not yet measured

In the paper

“For the general population, a daily protein intake of 1.2–1.6 g/kg is appropriate for supporting physical activity and imparting preventive/clinical benefits to musculoskeletal, gut microbiome, and cardiometabolic health [4,92,101,105].”

What the sources say

• Partly supported

  The Results report changes in body composition and gut-microbiome measures with intermittent fasting plus protein pacing in adults with overweight or obesity. The Methods describe protein as a percentage of calories, not a recommended daily intake of 1.2–1.6 g/kg. This intervention does not establish that the stated intake is appropriate for the general population or supports physical activity and all the listed health benefits. (LLM, conf=0.86)

  cites [4] Mohr AE, Sweazea KL, Bowes DA, et al. Gut microbiome remodeling and metabolomic profile improves in response to protein pacing with intermittent fasting versus continuous caloric restriction. Nat Commun. 2024; 15(1): 4155. doi: 10.1038/s41467-024-48355-5 PMC11133430 38806467 sourceExperimental — accuracy not yet measured
• Partly supported

  The Protein Quantity and Conclusions sections support 1.2–1.6 g/kg/day for improved weight management and cardiometabolic outcomes, and the Introduction notes preservation of lean mass. They do not establish that this intake is appropriate for the general population to support physical activity or benefit the gut microbiome. The Conclusions also caution that sustained effects are difficult to confirm when adherence is poor. (LLM, conf=0.88)

  cites [92] Leidy HJ, Clifton PM, Astrup A, et al. The role of protein in weight loss and maintenance. AJCN. 2015; 101(6): 1320S– 9S. doi: 10.3945/ajcn.114.084038 25926512 sourceExperimental — accuracy not yet measured
• Partly supported

  The Introduction says 1.2–1.6 g/kg/day has been suggested to improve or maintain muscle mass in healthy adults. The Abstract reports small muscle-related gains chiefly in people doing resistance exercise, rather than establishing that range as appropriate for the general population. Neither passage supports the attributed gut-microbiome or cardiometabolic benefits. (LLM, conf=0.89)

  cites [101] Nunes EA, Colenso-Semple L, McKellar SR, et al. Systematic review and meta-analysis of protein intake to support muscle mass and function in healthy adults. J Cachexia Sarcopenia Muscle. 2022; 13(2): 795– 810. doi: 10.1002/jcsm.12922 PMC8978023 35187864 sourceExperimental — accuracy not yet measured
• Partly supported

  The Abstract (page not provided) says many adults may benefit from protein intake above the RDA, particularly for muscle health during aging, inactivity, or metabolic dysfunction. The paper does not establish 1.2–1.6 g/kg per day as a recommendation for the general population or address gut-microbiome benefits; its Summary emphasizes that optimal intake depends on individual circumstances and meal composition. (LLM, conf=0.86)

  cites [105] Phillips SM, Paddon-Jones D, Layman DK. Optimizing adult protein intake during catabolic health conditions. Adv Nutr. 2020; 11(4): S1058– S69. doi: 10.1093/advances/nmaa047 PMC7360447 32666115 sourceExperimental — accuracy not yet measured

In the paper

“In the context of high-quality weight loss, the importance of adequate or optimal dietary protein intake cannot be overstated [92].”

What the sources say

• Supported

  The Introduction says increased dietary protein supports reductions in body weight and fat mass while preserving lean mass. The Conclusions likewise report benefits of higher-protein diets for weight management, while noting that long-term effects are harder to establish when dietary adherence is poor. This supports the broad claim that protein intake matters for high-quality weight loss. (LLM, conf=0.92)

  cites [92] Leidy HJ, Clifton PM, Astrup A, et al. The role of protein in weight loss and maintenance. AJCN. 2015; 101(6): 1320S– 9S. doi: 10.3945/ajcn.114.084038 25926512 source

In the paper

“Protein intakes ranging from 1.6 to 2.2 g/kg may optimize muscle anabolism when combined with resistance training [102,107–114].”

What the sources say

• Supported

  The Discussion (Muscle mass) reports a plateau in resistance-training-induced fat-free-mass gains at 1.62 g/kg/day and says that approximately 2.2 g/kg/day may be prudent for those seeking to maximize those gains. The Conclusion likewise identifies approximately 1.6 g/kg/day as sufficient during resistance training in healthy adults. (LLM, conf=0.90)

  cites [102] Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018; 52(6): 376– 384. doi: 10.1136/bjsports-2017-097608 PMC5867436 28698222 source
• Supported

  The Practical Recommendations section (5.1, Individuals in Energy Balance) states that daily protein intakes of approximately 1.6 to 2.2 g/kg can maximize muscle protein accretion with resistance exercise. The citing sentence’s hedged wording is consistent with that recommendation, though the paper gives it specifically for individuals in energy balance. (LLM, conf=0.93)

  cites [107] Stokes T, Hector AJ, Morton RW, et al. Recent perspectives regarding the role of dietary protein for the promotion of muscle hypertrophy with resistance exercise training. Nutrients. 2018; 10(2): 180. doi: 10.3390/nu10020180 PMC5852756 29414855 source
• Supported

  In §3.1 (Daily Intake), the review recommends at least 1.6 g/kg of protein for off-season bodybuilders and says that targeting closer to 2.2 g/kg may optimize the response for more athletes. The same section links these amounts to resistance-training-induced hypertrophy. (LLM, conf=0.91)

  cites [108] Iraki J, Fitschen P, Espinar S, et al. Nutrition recommendations for bodybuilders in the off-season: a narrative review. Sports (Basel). 2019; 7(7): 154. doi: 10.3390/sports7070154 PMC6680710 31247944 source
• Partly supported

  The Results and Discussion (page not provided) report that approximately 2.0 g/kg/day maximized postexercise whole-body anabolism in resistance-trained men. The paper discusses estimates near 1.6 and 2.2 g/kg/day, but does not establish that the entire range optimizes muscle-specific anabolism; its Discussion cautions that whole-body measurements may not accurately determine muscle-specific effects. (LLM, conf=0.86)

  cites [109] Mazzulla M, Abou Sawan S, Williamson E, et al. Protein intake to maximize whole-body anabolism during postexercise recovery in resistance-trained men with high habitual intakes is severalfold greater than the current recommended dietary allowance. J Nutr. 2020; 150(3): 505– 511. doi: 10.1093/jn/nxz249 31618421 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [110] Candow DG, Burke NC, Smith-Palmer T, et al. Effect of whey and soy protein supplementation combined with resistance training in young adults. Int J Sport Nutr Exerc Metab. 2006; 16(3): 233– 244. doi: 10.1123/ijsnem.16.3.233 16948480 source
• Partly supported

  The Dietary analyses table (Paragraph 28; page unavailable) reports protein intakes of about 2.0–2.1 g/kg/day in the whey-protein groups during resistance training. The conclusion in the same section says whey supplementation appeared to promote greater strength gains and muscle hypertrophy, but the study did not establish that the full 1.6–2.2 g/kg range optimizes muscle anabolism; it also cautions that the small groups limit firm conclusions. (LLM, conf=0.88)

  cites [111] Cribb PJ, Williams AD, Stathis CG, et al. Effects of whey isolate, creatine, and resistance training on muscle hypertrophy. Med Sci Sports Exerc. 2007; 39(2): 298– 307. doi: 10.1249/01.mss.0000247002.32589.ef 17277594 sourceExperimental — accuracy not yet measured
• Partly supported

  The Introduction and Discussion say that protein supplementation alongside resistance training can improve muscle hypertrophy, and Methods Table 1 reports mean intakes of 1.9 and 1.6 g/kg in the two groups. The paper does not identify 1.6–2.2 g/kg as an optimal range or establish that range for muscle anabolism; 2.2 g/kg is not reported as a target. (LLM, conf=0.88)

  cites [112] Yapici H, Gulu M, Yagin FH, et al. The effect of 8-weeks of combined resistance training and chocolate milk consumption on maximal strength, muscle thickness, peak power and lean mass, untrained, university-aged males. Front Physiol. 2023; 14: 1148494. doi: 10.3389/fphys.2023.1148494 PMC10064218 37007992 sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [113] Mhamed MB, Zarrouk F, Mrad M, et al. Effects of whey protein on body composition, biochemical profile, and high intensity physical performances in well-trained endurance runners. Sci Sports. 2024; 39(7): 588– 598. doi: 10.1016/j.scispo.2024.02.001 source
• Partly supported

  The Methods and Results report that protein-supplemented resistance-trained men gained muscle mass during an eight-week training program. The paper tested fixed supplement doses of 30 g/day whey and 10 g/day collagen, not total protein intakes of 1.6–2.2 g/kg or whether that range optimizes muscle anabolism. (LLM, conf=0.86)

  cites [114] Seyhan S, Jourkesh M, Salatin A, et al. The combined effects of whey protein and collagen supplementation on bone mineral density and muscle mass in resistance-trained men: a randomized controlled trial. BMC Sports Sci Med Rehabil. 2026; 1846. doi: 10.1186/s13102-026-01846-y 42426859 sourceExperimental — accuracy not yet measured

In the paper

“In physically active and athletic populations, distributing protein across 3 or more protein-rich meals (or eating occasions) per day may support lean mass retention and performance during sustained energy deficits [55,56].”

What the sources say

• Partly supported

  Section 6 (Frequency; page unavailable) recommends 3–6 protein-rich feedings for resistance-trained athletes during a fat-loss phase, and Section 4.1 (Protein; page unavailable) discusses preserving fat-free mass during sustained energy deficits. The review does not establish that this meal frequency supports performance, and its discussion of fat-free-mass outcomes with different feeding schedules reports mixed results. The claim also extends the recommendation beyond resistance-trained athletes to physically active populations generally. (LLM, conf=0.84)

  cites [55] Ruiz-Castellano C, Espinar S, Contreras C, et al. Achieving an optimal fat loss phase in resistance-trained athletes: a narrative review. Nutrients. 2021; 13(9): 3255. doi: 10.3390/nu13093255 PMC8471721 34579132 sourceExperimental — accuracy not yet measured
• Partly supported

  In the meal-frequency discussion (page not available), the paper suggests that extreme meal frequencies may threaten lean-mass preservation during bodybuilding contest preparation and describes 3–6 meals with at least 20 g protein each as a moderate range. It does not establish that distributing protein across three or more meals supports performance during sustained energy deficits: the reported performance finding involved added snacks and calories, and the paper notes a lack of corroborating chronic performance trials. (LLM, conf=0.84)

  cites [56] Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr. 2014; 11: 20. doi: 10.1186/1550-2783-11-20 PMC4033492 24864135 sourceExperimental — accuracy not yet measured

In the paper

“A more recent systematic review and meta-regression by Refalo et al. [116] revisited Helms et al.’s research question and included an additional decade of studies (29 in total), with analyses of non-obese, resistance-trained individuals in hypocaloric conditions. A daily protein intake of 1.9–3.2 g/kg BW, or 2.5–4.2 g/kg FFM, was associated with greater retention of fat-free mass.”

What the sources say

• Supported

  Split into 2 atoms — 2 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites [116] Refalo MC, Trexler ET, Helms ER. Effect of dietary protein on fat-free mass in energy restricted, resistance-trained individuals: an updated systematic review with meta-regression. Strength Cond J. 2026; 48(4): 398– 412. doi: 10.1519/SSC.0000000000000888 source

In the paper

“Corroborating this point, a systematic review and meta-analysis by Murphy and Koehler [87] examined RCTs with a minimum 3-week duration; and found that energy deficits at or beyond 500 kcal/day can impair lean mass gains in subjects undergoing resistance training.”

What the sources say

• Supported

  The Inclusion criteria (§2.2) specify at least three weeks of resistance training and include randomized controlled trials in Analysis A. The Meta-regression (§3.5) estimates that a deficit of about 500 kcal/day would result in no lean-mass gain, supporting the claim that such deficits can impair gains. (LLM, conf=0.91)

  cites [87] Murphy C, Koehler K. Energy deficiency impairs resistance training gains in lean mass but not strength: a meta-analysis and meta-regression. Scand J Med Sci Sports. 2022; 32(1): 125– 137. doi: 10.1111/sms.14075 34623696 source

In the paper

“Along similar lines to the findings of Helms et al. [115] and Refalo et al. [116], Barakat et al. [117] reported that a protein intake of 2.6–3.5 g/kg FFM may increase the likelihood and magnitude of recomposition in resistance-trained subjects.”

What the sources say

• Supported

  The Conclusion states that consuming 2.6–3.5 g/kg of fat-free mass may increase the likelihood or magnitude of recomposition. The paper discusses this recommendation in the context of resistance training and trained individuals. (LLM, conf=0.94)

  cites [117] Barakat C, Pearson J, Escalante G, et al. Body recomposition: can trained individuals build muscle and lose fat at the same time? Strength Cond J. 2020; 42(5): 7– 21. doi: 10.1519/SSC.0000000000000584 source

In the paper

“Smith et al. [129] reported a lack of sex-based differences in mixed MPS during a fasted or a hyperinsulinemic-hyperaminoacidemic state in young and middle-aged men and women.”

What the sources say

• Supported

  The Methods section identifies the measure as mixed muscle protein synthesis. The Abstract describes young and middle-aged men and women studied after an overnight fast and during a hyperinsulinemic-hyperaminoacidemic clamp; the Results report no sex difference in basal synthesis or in the response to the clamp. (LLM, conf=0.92)

  cites [129] Smith GI, Atherton P, Reeds DN, et al. No major sex differences in muscle protein synthesis rates in the postabsorptive state and during hyperinsulinemia-hyperaminoacidemia in middle-aged adults. J Appl Physiol (1985). 2009; 107(4): 1308– 1315. doi: 10.1152/japplphysiol.00348.2009 PMC2763845 19644030 source

In the paper

“These subjective effects are accompanied by objective mechanisms, including decreased ghrelin, and increased cholecystokinin and glucagon-like peptide-1 (GLP-1) [95,96].”

What the sources say

• Supported

  The Proteins section links protein-related satiety to the release of gut peptides including CCK and GLP-1. The section Do Some Macronutrient Sources Suppress FI Beyond Their Provision of Energy? says protein contributes to CCK release, has a sustained effect on GLP-1, and, like other macronutrients, contributes to decreased postprandial ghrelin. No page numbers are provided in the supplied passages. (LLM, conf=0.90)

  cites [95] Bellissimo N, Akhavan T. Effect of macronutrient composition on short-term food intake and weight loss. Adv Nutr. 2015; 6(3): 302S– 8S. doi: 10.3945/an.114.006957 PMC4424768 25979503 source
• Partly supported

  The “Endocrine Responses to Protein” section reports increased GLP-1 and CCK after a whey preload and reduced ghrelin with some protein sources. But it also says gut-peptide responses to protein are weak and inconsistent: other studies found no effect on CCK or ghrelin, and ghrelin increased with animal protein. The proposed hormone changes are therefore supported in particular conditions, not as a general mechanism accompanying protein’s effects on hunger and fullness. (LLM, conf=0.88)

  cites [96] Carreiro AL, Dhillon J, Gordon S, et al. The macronutrients, appetite, and energy intake. Annu Rev Nutr. 2016; 36: 73– 103. doi: 10.1146/annurev-nutr-121415-112624 PMC4960974 27431364 sourceExperimental — accuracy not yet measured

In the paper

“Importantly, there were no statistical between-group differences in protein and total caloric intake.”

What the sources say

• Partly supported

  The Results state that total energy intake did not differ between diet groups at baseline or any later time point. They also report significant between-group differences in protein intake at every time point after randomization (all P ≤ .001), so the protein part of the claim is incorrect. (LLM, conf=0.92)

  cites [135] Gardner CD, Trepanowski JF, Del Gobbo LC, et al. Effect of low-fat vs low-carbohydrate diet on 12-Month weight loss in overweight adults and the association with genotype pattern or insulin secretion: the DIETFITS randomized clinical trial. J Am Med Assoc. 2018; 319(7): 667– 679. doi: 10.1001/jama.2018.0245 PMC5839290 29466592 sourceExperimental — accuracy not yet measured

In the paper

“With a KD, ketonemia is maximal within approximately 2 weeks [152].”

What the sources say

• Partly supported

  The Overnight fasted plasma metabolite and hormone concentrations section reports that circulating ketones increased during the ketogenic diet, and the Figure 4 caption describes measurements across the diet period (page unavailable). Neither passage states that ketonemia reached its maximum within approximately two weeks; that timing is unsupported by the text of our copy. (LLM, conf=0.83)

  cites [152] Hall KD, Chen KY, Guo J, et al. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men. AJCN. 2016; 104(2): 324– 333. doi: 10.3945/ajcn.116.133561 PMC4962163 27385608 sourceExperimental — accuracy not yet measured

In the paper

“Fat oxidation increases via the KD reaches maximal levels and plateaus within the first week of the diet [152].”

What the sources say

• Supported

  The EE and RQ section reports that 24-hour respiratory quotient fell at the start of the ketogenic diet and remained approximately constant through the study, indicating a rapid and persistent increase in fat oxidation. The Figure 3 caption places the decrease within the first week. This supports the claimed early rise and plateau in the men studied. (LLM, conf=0.91)

  cites [152] Hall KD, Chen KY, Guo J, et al. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men. AJCN. 2016; 104(2): 324– 333. doi: 10.3945/ajcn.116.133561 PMC4962163 27385608 source

In the paper

“However, protein intakes as high as 1.7–2.2 g/kg have resulted in targeted levels of ketosis, with blood ketone levels ranging 0.7–1.8 mmol/L [155–157].”

What the sources say

• ?Not checked — no full text of the sourcecites [155] Wilson JM, Lowery RP, Roberts MD, et al. Effects of ketogenic dieting on body composition, strength, power, and hormonal profiles in resistance training men. J Strength Cond Res. 2020; 34(12): 3463– 3474. doi: 10.1519/JSC.0000000000001935 28399015 source
• Partly supported

  Table 2 (shown under Discussion; page not supplied) reports that the low-carbohydrate runners consumed 2.1 ± 0.6 g/kg of protein daily, and the Discussion reports approximately threefold higher circulating ketones than in the high-carbohydrate group. Our copy does not give the claimed 0.7–1.8 mmol/L range or establish that protein intake produced a targeted ketone level. (LLM, conf=0.85)

  cites [156] Volek JS, Freidenreich DJ, Saenz C, et al. Metabolic characteristics of keto-adapted ultra-endurance runners. Metabolism. 2016; 65(3): 100– 110. doi: 10.1016/j.metabol.2015.10.028 26892521 sourceExperimental — accuracy not yet measured
• Partly supported

  In Results > Diet and training compliance (page unavailable), the LCHF group’s mean protein intake was 2.2 g/kg. Results > 25 km long walk reports blood ketones maintained at approximately 1 mmol/L after treatment. The paper therefore supports ketosis alongside a high protein intake, but these passages do not establish the stated 1.7–2.2 g/kg protein range or the full 0.7–1.8 mmol/L ketone range. (LLM, conf=0.86)

  cites [157] Burke LM, Ross ML, Garvican-Lewis LA, et al. Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. J Physiol. 2017; 595(9): 2785– 2807. doi: 10.1113/JP273230 PMC5407976 28012184 sourceExperimental — accuracy not yet measured

In the paper

“KDs induce a state of ketosis – a shift in metabolic substrate use, whereby ketones (acetoacetate, acetone, and beta-hydroxybutyrate) are produced as an alternative fuel source to glucose [148].”

What the sources say

• Supported

  The Ketogenesis section identifies acetoacetate, beta-hydroxybutyrate, and acetone as ketone bodies produced during ketogenesis and describes them as an alternative energy source to glucose. The Ketosis and ketogenic diets section says ketogenic diets promote a relatively constant state of ketosis. (LLM, conf=0.93)

  cites [148] Leaf A, Rothschild JA, Sharpe TM, et al. International society of sports nutrition position stand: ketogenic diets. J Int Soc Sports Nutr. 2024; 21(1): 2368167. doi: 10.1080/15502783.2024.2368167 PMC11212571 38934469 source

In the paper

“The reductions in body fat content were not statistically significant between the groups (1.97% and 2.15%, respectively).”

What the sources say

• Supported

  The Secondary Outcomes section states that body fat percentage did not differ significantly between groups. Table 3 reports 12-month reductions of 1.97 percentage points for the healthy low-fat group and 2.15 for the healthy low-carbohydrate group, with a between-group difference whose 95% confidence interval includes zero. (LLM, conf=0.95)

  cites [135] Gardner CD, Trepanowski JF, Del Gobbo LC, et al. Effect of low-fat vs low-carbohydrate diet on 12-Month weight loss in overweight adults and the association with genotype pattern or insulin secretion: the DIETFITS randomized clinical trial. J Am Med Assoc. 2018; 319(7): 667– 679. doi: 10.1001/jama.2018.0245 PMC5839290 29466592 source

In the paper

“Recent umbrella reviews (quantitative reviews containing multiple meta-analyses) have reported that KDs tend to increase low-density lipoprotein (LDL) cholesterol [168,169].”

What the sources say

• Supported

  The Results (section 3.2) report weak evidence that ketogenic diets may increase LDL in people with overweight or obesity without type 2 diabetes, and that ketogenic diets combined with physical activity increase LDL in people with overweight or obesity. This supports the citing sentence’s hedged wording, though the reported findings concern those populations and the evidence is weak. (LLM, conf=0.91)

  cites [168] Chen S, Su X, Feng Y, et al. Ketogenic diet and multiple health outcomes: an umbrella review of meta-analysis. Nutrients. 2023; 15(19): 4161. doi: 10.3390/nu15194161 PMC10574428 37836444 source
• Supported

  The Discussion states that the review’s aggregate results confirm an increase in LDL-C with ketogenic diets. The Results section also lists increased LDL-C among the adverse outcomes associated with these diets, supporting the citing sentence’s qualified wording, “tend to increase.” (LLM, conf=0.94)

  cites [169] Patikorn C, Saidoung P, Pham T, et al. Effects of ketogenic diet on health outcomes: an umbrella review of meta-analyses of randomized clinical trials. BMC Med. 2023; 21(1): 196. doi: 10.1186/s12916-023-02874-y PMC10210275 37231411 source

In the paper

“Fasting or severe energy restriction can also induce ketosis [150].”

What the sources say

• Supported

  The Introduction explains how fasting leads to ketone-body production, and the Abstract states that long-term fasting triggered ketosis. The Fasting Program section specifies that participants consumed only 75–250 kcal/day, supporting the claim about severe energy restriction as well. (LLM, conf=0.94)

  cites [150] Grundler F, Mesnage R, Ruppert PMM, et al. Long-term fasting-induced ketosis in 1610 subjects: metabolic regulation and safety. Nutrients. 2024; 16(12): 1849. doi: 10.3390/nu16121849 PMC11206495 38931204 source

In the paper

“Indeed, fat oxidation rates are elevated in KDs [154].”

What the sources say

• Supported

  The section “Could Fat Be the Macronutrient of Choice to Produce Energy and Curb Obesity?” (page not provided) says that dietary carbohydrate deprivation, together with increased fat consumption, shifts metabolism into fat oxidation. This supports the claim about ketogenic diets; the paper does not give a numerical oxidation rate in that passage. (LLM, conf=0.86)

  cites [154] Biesiekierska M, Strigini M, Sliwinska A, et al. The impact of ketogenic nutrition on obesity and metabolic health: mechanisms and clinical implications. Nutr Rev. 2025; 83(10): 1957– 1972. doi: 10.1093/nutrit/nuaf010 PMC12422014 40036324 source

In the paper

“Carbohydrate (or total energy) restriction can raise circulating ketone levels to a range of ~0.5–3 mmol/L [104].”

What the sources say

• Supported

  The Ketogenic diets section states that, depending on the degree of carbohydrate or total-energy restriction, a ketogenic diet can raise circulating ketone levels to approximately 0.5–3 mmol/L. This directly supports the cited sentence. (LLM, conf=0.95)

  cites [104] Aragon AA, Schoenfeld BJ, Wildman R, et al. International society of sports nutrition position stand: diets and body composition. J Int Soc Sports Nutr. 2017; 14: 16. doi: 10.1186/s12970-017-0174-y PMC5470183 28630601 source

In the paper

“Subjects in both groups were unable to maintain their original (20 g) fat and carbohydrate intake assignments during the initial 8 weeks.”

What the sources say

• Partly supported

  The Weight Loss Intervention section says both groups were instructed to reduce their assigned nutrient to 20 g/day during the first 8 weeks, then gradually add it back. Table 2 reports mean intakes above 20 g/day at 3 months, but the paper does not report intake during the initial 8 weeks, so it does not establish that participants were unable to maintain the target then. (LLM, conf=0.86)

  cites [135] Gardner CD, Trepanowski JF, Del Gobbo LC, et al. Effect of low-fat vs low-carbohydrate diet on 12-Month weight loss in overweight adults and the association with genotype pattern or insulin secretion: the DIETFITS randomized clinical trial. J Am Med Assoc. 2018; 319(7): 667– 679. doi: 10.1001/jama.2018.0245 PMC5839290 29466592 sourceExperimental — accuracy not yet measured

In the paper

“Favorable shifts in body composition (lean mass gain and fat mass reduction) can occur when training is productive, thereby leading to the illusion of stagnation, when recomposition actually occurs [117].”

What the sources say

• Partly supported

  The Introduction defines body recomposition as gaining muscle mass while losing fat mass, and the Conclusion says it can occur in trained individuals. The cited paper does not address the claimed illusion of stagnation or explain how recomposition might create it. (LLM, conf=0.84)

  cites [117] Barakat C, Pearson J, Escalante G, et al. Body recomposition: can trained individuals build muscle and lose fat at the same time? Strength Cond J. 2020; 42(5): 7– 21. doi: 10.1519/SSC.0000000000000584 sourceExperimental — accuracy not yet measured

In the paper

“Greater weight loss was associated with greater increases in ghrelin levels.”

What the sources say

• Partly supported

  The Results sections on circulating total ghrelin report that greater weight loss was associated with greater increases in total ghrelin in both RCTs and non-RCTs. The claim does not specify total ghrelin: the Results on acylated ghrelin report a decrease with greater weight loss in RCTs and no significant association in non-RCTs. (LLM, conf=0.88)

  cites [189] Jin Z, Li J, Thackray AE, et al. Fasting appetite-related gut hormone responses after weight loss induced by calorie restriction, exercise, or both in people with overweight or obesity: a meta-analysis. Int J Obes (Lond). 2025; 49(5): 776– 792. doi: 10.1038/s41366-025-01726-4 PMC12095072 39929932 sourceExperimental — accuracy not yet measured

In the paper

“Moreover, Bonomi et al. [179] found that 13% weight loss decreased activity energy expenditure (AEE) by ~143 kcal.”

What the sources say

• Supported

  The Abstract reports a 13±4% reduction in body weight and a 0.6±0.4 MJ/day decrease in AEE. The Results confirm the AEE decrease; 0.6 MJ is approximately 143 kcal, so the cited figure is a valid conversion of the daily change. (LLM, conf=0.94)

  cites [179] Bonomi AG, Soenen S, Goris AH, et al. Weight-loss induced changes in physical activity and activity energy expenditure in overweight and obese subjects before and after energy restriction. PLoS One. 2013; 8(3): e59641. doi: 10.1371/journal.pone.0059641 PMC3605325 23555733 source

In the paper

“Adaptations to weight loss (imposed by changes in diet and/or physical activity) are governed by a complex neuroendocrinological network that maintains a bidirectional relationship with a wide range of bodily tissues and organ systems, which can ultimately influence eating behavior and energetic balance [172–175].”

What the sources say

• ?Not checked — no full text of the sourcecites [172] Boguszewski CL, Paz-Filho G, Velloso LA. Neuroendocrine body weight regulation: integration between fat tissue, gastrointestinal tract, and the brain. Endokrynol Pol. 2010; 61(2): 194– 206. 20464707
• ?Not checked — no full text of the sourcecites [173] Wilson JL, Enriori PJ. A talk between fat tissue, gut, pancreas and brain to control body weight. Mol Cell Endocrinol. 2015; 418(Pt 2): 108– 119 26316427. doi: 10.1016/j.mce.2015.08.022. 26316427 source
• Partly supported

  Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites [174] Iizuka K, Machida T, Hirafuji M. Skeletal muscle is an endocrine organ. J Pharmacol Sci. 2014; 125(2): 125– 131. doi: 10.1254/jphs.14r02cp 24859778 sourceExperimental — accuracy not yet measured
• Supported

  Split into 2 atoms — 2 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites [175] Paspala I, Katsiki N, Kapoukranidou D, et al. The role of psychobiological and neuroendocrine mechanisms in appetite regulation and obesity. Open Cardiovasc Med J. 2012; 6: 147– 155. doi: 10.2174/1874192401206010147 PMC3549543 23346258 source

In the paper

“These alterations in appetite-regulatory hormone levels occurred at similar magnitude regardless of the method of weight loss (caloric restriction, exercise, or a combination).”

What the sources say

• Partly supported

  The Results (subgroup analysis) and Discussion report no statistically significant differences in hormone responses among calorie restriction, exercise, and their combination. But the claim presents this as established similarity in magnitude across all methods: some hormone comparisons could not be made, and the Discussion says the effect of combined restriction and exercise remains uncertain because studies were limited. (LLM, conf=0.85)

  cites [189] Jin Z, Li J, Thackray AE, et al. Fasting appetite-related gut hormone responses after weight loss induced by calorie restriction, exercise, or both in people with overweight or obesity: a meta-analysis. Int J Obes (Lond). 2025; 49(5): 776– 792. doi: 10.1038/s41366-025-01726-4 PMC12095072 39929932 sourceExperimental — accuracy not yet measured

In the paper

“The constrained energy expenditure model proposes that increases in physical activity do not necessarily produce proportional increases in total daily energy expenditure; additional energy costs may be partially offset by reductions in other components of expenditure [180].”

What the sources say

• Supported

  Split into 2 atoms — 2 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  cites [180] Pontzer H, Durazo-Arvizu R, Dugas LR, et al. Constrained total energy expenditure and metabolic adaptation to physical activity in adult humans. Curr Biol. 2016; 26(3): 410– 417. doi: 10.1016/j.cub.2015.12.046 PMC4803033 26832439 source

In the paper

“Clark’s results notwithstanding [222], frequent self-weighing has been consistently associated with favorable weight loss outcomes [223,224].”

What the sources say

• Supported

  The Introduction says regular self-weighing is consistently associated with weight loss and weight-loss maintenance. The Discussion’s Conclusions report that this study also found an association between frequent self-weighing and favorable weight-loss outcomes in a free-living setting. The paper describes an association, not a causal effect. (LLM, conf=0.94)

  cites [223] Vuorinen AL, Helander E, Pietila J, et al. Frequency of self-weighing and weight change: cohort study with 10,000 smart scale users. J Med Internet Res. 2021; 23(6): e25529. doi: 10.2196/25529 PMC8277333 34075879 source
• Supported

  The Results report significantly greater weight loss among daily weighers than among those weighing less than daily. The Introduction describes emerging evidence for this association, and the Discussion reports similar findings from another trial. Our copy does not provide page numbers for these passages. (LLM, conf=0.90)

  cites [224] Steinberg DM, Bennett GG, Askew S, et al. Weighing every day matters: daily weighing improves weight loss and adoption of weight control behaviors. J Acad Nutr Diet. 2015; 115(4): 511– 518. doi: 10.1016/j.jand.2014.12.011 PMC4380831 25683820 source

In the paper

“Among individuals with overweight and obesity, energy intake is under-reported by ~25%–50% [214,215].”

What the sources say

• Supported

  The Introduction says overweight individuals tend to underreport dietary intake by about 20–50%, depending on the population and assessment method. The claimed ~25–50% range is a close approximation, though the source gives 20% as its lower bound. (LLM, conf=0.87)

  cites [214] Park HA, Lee JS, Kuller LH. Underreporting of dietary intake by body mass index in premenopausal women participating in the healthy women study. Nutr Res Pract. 2007; 1(3): 231– 236. doi: 10.4162/nrp.2007.1.3.231 PMC2849028 20368944 source
• ?Not checked — no full text of the sourcecites [215] Lichtman SW, Pisarska K, Berman ER, et al. Discrepancy between self-reported and actual caloric intake and exercise in obese subjects. NEJM. 1992; 327(27): 1893– 1898. doi: 10.1056/NEJM199212313272701 1454084 source

In the paper

“The evidence at-large shows a lack of differential effects between the intermittent fasting variants (alternate-day fasting, time-restricted eating, and twice-weekly fasting) and continuous energy restriction on anthropometric outcomes”

• Also stated in: § Summary and conclusions · plain

  “Intermittent energy restriction models have accumulated a substantial body of evidence of their similar effect to continuous energy restriction on body weight and body fat reduction.”

In the paper

“Intra-day meal frequency (as opposed to total daily nutrition) does not tend to crucially influence body weight and body fat reduction.”

In the paper

“Resistance training and sufficient protein intake are indispensable mitigators of lean mass loss in a sustained caloric deficit, regardless of the diet type or variant.”

• Also stated in: § Position of the International Society of Sports Nutrition (ISSN) · plain

  “Resistance training and sufficient protein intake are indispensable mitigators of lean mass loss in a sustained caloric deficit, regardless of the diet type or variant.”

• Also stated in: § Summary and conclusions · plain

  “Lean mass loss associated with the range of diet types can be substantially attenuated with progressive resistance training and sufficient protein intake.”

In the paper

“higher intakes of 1.9–3.2 g/kg BW can maximize lean mass retention in lean, resistance-trained individuals sustaining hypocaloric conditions.”

In the paper

“since the range of ketogenic to low-fat diets performs similarly.”

In the paper

“no lower or upper limits can universally be prescribed to optimize outcomes.”

In the paper

“Metabolic adaptations that reduce energy expenditure, including adaptive thermogenesis, and impair gut microbial diversity, can often be attenuated by strategic dietary and exercise programming that foster nutrient-absorption and partitioning, and metabolic flexibility.”

In the paper

“Intra-day meal frequency (as opposed to total daily nutrition) does not tend to crucially influence body weight and body fat reduction.”

In the paper

“Very-low-energy diets (<800 kcal/day) and low-energy diets (800–1200 kcal/day) produce greater short-term weight loss but lack long-term advantages over less aggressive energy restrictions, such as calorie-controlled diets.”

In the paper

“they also tend to decrease fat-free mass to a greater degree than higher-carbohydrate comparators, particularly in shorter trials where glycogen and total body water shifts can influence estimates.”

In the paper

“It can occur in response to hypocaloric conditions and weight loss”

In the paper

“These aggressive diets may increase lean mass loss, although adequate protein intake and resistance training may mitigate this risk.”

In the paper

“These aggressive diets may increase lean mass loss, although adequate protein intake and resistance training may mitigate this risk.”

In the paper

“Caution is warranted about insufficiencies in vitamins, minerals, fiber, and other nutrients.”

In the paper

“The dietary carbohydrate‒fat proportion can be individualized to personal preference for the goal of weight loss”

In the paper

“converge toward reducing energy expenditure to fulfill the body’s drive toward neutralizing disruptions to homeostasis imposed by the caloric deficit.”

In the paper

“it may attenuate substantially upon attainment of weight stability.”

In the paper

“optimizing this process involves the attenuation of lean mass loss, which characterizes high-quality weight loss [7].”

What the sources say

• ?Not checked — no full text of the sourcecites [7] Churchward-Venne TA, Murphy CH, Longland TM, et al. Role of protein and amino acids in promoting lean mass accretion with resistance exercise and attenuating lean mass loss during energy deficit in humans. Amino Acids. 2013; 45(2): 231– 240. doi: 10.1007/s00726-013-1506-0 23645387 source

In the paper

“Very-low-energy diets (<800 kcal/day) and low-energy diets (800–1200 kcal/day) produce greater short-term weight loss but lack long-term advantages over less aggressive energy restrictions, such as calorie-controlled diets.”

In the paper

“Daily protein intakes ranging 1.6–2.2 g/kg BW combined with resistance training may optimize muscle anabolism”

In the paper

“but it is not an inevitable response”

In the paper

“The evidence at-large shows a lack of differential effects between intermittent fasting variants (alternate-day fasting, time-restricted eating, and twice-weekly fasting) and continuous energy restriction on anthropometric outcomes”

In the paper

“Ketogenic diets are effective at bodyweight and body fat reduction”

In the paper

“Casting doubt on the universal superiority of rapid weight loss, a systematic review and meta-analysis by Ashtary-Larky et al. [52] determined a similar magnitude of weight loss between rapid and gradual weight loss in subjects with overweight and obesity.”

What the sources say

• ?Not checked — no full text of the sourcecites [52] Ashtary-Larky D, Bagheri R, Abbasnezhad A, et al. Effects of gradual weight loss v. Rapid weight loss on body composition and RMR: a systematic review and meta-analysis. Br J Nutr. 2020; 124(11): 1121– 1132. doi: 10.1017/S000711452000224X 32576318 source

In the paper

“lean mass loss during aggressive caloric restriction, especially in subjects with obesity, can be mitigated or prevented altogether via increased protein intake and resistance training [36,37].”

What the sources say

• ?Not checked — no full text of the sourcecites [36] Bryner RW, Ullrich IH, Sauers J, et al. Effects of resistance vs. Aerobic training combined with an 800 calorie liquid diet on lean body mass and resting metabolic rate. J Am Coll Nutr. 1999; 18(2): 115– 121. doi: 10.1080/07315724.1999.10718838 10204826 source
• ?Not checked — no full text of the sourcecites [37] Jo E, Worts PR, Elam ML, et al. Resistance training during a 12-week protein supplemented VLCD treatment enhances weight-loss outcomes in obese patients. Clin Nutr. 2019; 38(1): 372– 382. doi: 10.1016/j.clnu.2017.12.015 29352654 source

In the paper

“No fasting-specific cardiometabolic advantages were observed.”

What the sources say

• ?Not checked — no full text of the sourcecites [72] Templeman I, Smith HA, Chowdhury E, et al. A randomized controlled trial to isolate the effects of fasting and energy restriction on weight loss and metabolic health in lean adults. Sci Transl Med. 2021; 13(598). doi: 10.1126/scitranslmed.abd8034 34135111 source

In the paper

“In the 75:75 group, 92% of weight loss was attributable to fat mass, compared with only 46% in the hypocaloric ADF group (0:150), with the remainder attributable to fat-free mass.”

What the sources say

• ?Not checked — no full text of the sourcecites [72] Templeman I, Smith HA, Chowdhury E, et al. A randomized controlled trial to isolate the effects of fasting and energy restriction on weight loss and metabolic health in lean adults. Sci Transl Med. 2021; 13(598). doi: 10.1126/scitranslmed.abd8034 34135111 source

In the paper

“The greater initial weight loss achieved with VLEDs does not consistently translate into superior long-term weight loss.”

In the paper

“Varady and Gabel [66] reported that ADF results in ~3%–7% body weight reduction in trials ranging from 2 to 6 months.”

What the sources say

• ?Not checked — no full text of the sourcecites [66] Varady KA, Gabel K. Safety and efficacy of alternate day fasting. Nat Rev Endocrinol. 2019; 15(12): 686– 687. doi: 10.1038/s41574-019-0270-y 31558778 source

In the paper

“For normal-weight or lean subjects, VLEDs and LEDs may potentially pose the risk of lean mass loss, regardless of protein and exercise training interventions.”

What the sources say

• ?Not checked — no full text of the sourcecites [40] Pasiakos SM, Cao JJ, Margolis LM, et al. Effects of high-protein diets on fat-free mass and muscle protein synthesis following weight loss: a randomized controlled trial. FASEB J. 2013; 27(9): 3837– 3847. doi: 10.1096/fj.13-230227 23739654 source

In the paper

“Weight loss on VLEDs is rapid, with rates ranging from ~1.5 to 2.5 kg per week.”

In the paper

“The tendency towards greater reductions in total body mass via ADF compared to other IF variants is not necessarily surprising, since it can impose a greater weekly net caloric deficit.”

In the paper

“Plausible explanations for these differences are likely due to the high-quality, nutrient-dense, protein-pacing “feeding” days combined with the two IF days in the Arciero et al. studies, despite identical overall energy intake levels compared with those of the CER group.”

In the paper

“A recurrent theme in the pooled analyses at-large is a lack of differential effects between IF variants on anthropometric outcomes.”

In the paper

“Thus, the divergent findings may largely reflect differences in the magnitude of energy restriction rather than an intrinsic advantage of fasting for fat loss.”

In the paper

“The 4:3 model could potentially represent a more feasible alternative to ADF while still retaining its aggressive energy deficit – granted that resistance training and sufficient protein are provided.”

In the paper

“However, a 17-study systematic review by Sallahewa et al. [47] reported no major adverse events except for one study involving a non-fatal myocardial infarction.”

What the sources say

• ?Not checked — no full text of the sourcecites [47] Sellahewa L, Khan C, Lakkunarajah S, et al. A systematic review of evidence on the use of very low calorie diets in people with diabetes. Curr Diabetes Rev. 2017; 13(1): 35– 46. doi: 10.2174/1573399812666151005123431 26435354 source

In the paper

“The protein feeding distribution (across the meals/snacks/day) can potentially influence lean mass preservation.”

In the paper

“Resistance training has been shown to mitigate MPB during an aggressive (40%) short-term (10-day) caloric deficit [86].”

What the sources say

• ?Not checked — no full text of the sourcecites [86] Hector AJ, McGlory C, Damas F, et al. Pronounced energy restriction with elevated protein intake results in no change in proteolysis and reductions in skeletal muscle protein synthesis that are mitigated by resistance exercise. FASEB J. 2018; 32(1): 265– 275. doi: 10.1096/fj.201700158RR 28899879 source

In the paper

“A 6-study systematic review by Helms et al. [115] reported that a daily protein intake of 2.3–3.1 g/kg FFM was most effective for body composition outcomes in lean, resistance-trained individuals undergoing energy restriction.”

What the sources say

• ?Not checked — no full text of the sourcecites [115] Helms ER, Zinn C, Rowlands DS, et al. A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes. Int J Sport Nutr Exerc Metab. 2014; 24(2): 127– 138. doi: 10.1123/ijsnem.2013-0054 24092765 source

In the paper

“These findings support an independent role of macronutrient quality beyond overall caloric intake as a primary metabolic advantage during caloric restriction.”

In the paper

“However, this hypothesis has been repeatedly refuted in tightly controlled chamber calorimeter studies examining 24-hour energy expenditure of widely disparate frequencies, ranging 2–7 meals daily [79,80].”

What the sources say

• ?Not checked — no full text of the sourcecites [79] Taylor MA, Garrow JS. Compared with nibbling, neither gorging nor a morning fast affect short-term energy balance in obese patients in a chamber calorimeter. Int J Obes Relat Metab Disord. 2001; 25(4): 519– 528. doi: 10.1038/sj.ijo.0801572 11319656 source
• Not checked yetcites [80] Verboeket-van de Venne WP, Westerterp KR. Influence of the feeding frequency on nutrient utilization in man: consequences for energy metabolism. Eur J Clin Nutr. 1991; 45(3): 161– 169. 1905998

In the paper

“On a final note, the available evidence does not indicate sex-specific differences in the MPS response to protein feeding.”

In the paper

“Longitudinal studies have largely failed to detect a consistent advantage of higher versus lower meal frequencies for body weight management.”

In the paper

“Intermittent fasting generally produces body composition and cardiometabolic outcomes comparable to continuous energy restriction.”