Cited by 2,143Diet and metabolism studiesDietary Effects on HealthNutritional Studies and Diet

Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet

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Shai, Iris, Schwarzfuchs, Dan, Henkin, Yaakov, Shahar, Danit R., Witkow, Shula, Greenberg, Ilana, Golan, Rachel, Fraser, Drora +15 more·2008·New England Journal of Medicine

Abstract

BACKGROUND: Trials comparing the effectiveness and safety of weight-loss diets are frequently limited by short follow-up times and high dropout rates. METHODS: In this 2-year trial, we randomly assigned 322 moderately obese subjects (mean age, 52 years; mean body-mass index [the weight in kilograms divided by the square of the height in meters], 31; male sex, 86%) to one of three diets: low-fat, restricted-calorie; Mediterranean, restricted-calorie; or low-carbohydrate, non-restricted-calorie. RESULTS: The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years. The Mediterranean-diet group consumed the largest amounts of dietary fiber and had the highest ratio of monounsaturated to saturated fat (P<0.05 for all comparisons among treatment groups). The low-carbohydrate group consumed the smallest amount of carbohydrates and the largest amounts of fat, protein, and cholesterol and had the highest percentage of participants with detectable urinary ketones (P<0.05 for all comparisons among treatment groups). The mean weight loss was 2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet group, and 4.7 kg for the low-carbohydrate group (P<0.001 for the interaction between diet group and time); among the 272 participants who completed the intervention, the mean weight losses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The relative reduction in the ratio of total cholesterol to high-density lipoprotein cholesterol was 20% in the low-carbohydrate group and 12% in the low-fat group (P=0.01). Among the 36 subjects with diabetes, changes in fasting plasma glucose and insulin levels were more favorable among those assigned to the Mediterranean diet than among those assigned to the low-fat diet (P<0.001 for the interaction among diabetes and Mediterranean diet and time with respect to fasting glucose levels). CONCLUSIONS: Mediterranean and low-carbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions. (ClinicalTrials.gov number, NCT00160108.)

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Crossref · 10.1056/nejmoa0708681

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  • Low-carbohydrate diet trials have reported very low urinary ketosis after six months, suggesting that sustaining low carbohydrate intake is futile for most overweight people.

    “In addition, trials of low-carbohydrate diets have reported a very low incidence of urinary ketosis after 6 months,6,8,12 suggesting that in most overweight people, it is futile to sustain a low intake of carbohydrates.”

    From Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates (2009) · cites this paper as [12]

    The Dietary Intake, Energy Expenditure, and Urinary Ketones section reports low detectable urinary ketones at 24 months (8.3% in the low-carbohydrate group), not at six months. Contrary to the claimed futility of sustaining low carbohydrate intake, it reports lower carbohydrate intake in that group, and the Discussion describes the diet as an effective alternative after two years. (LLM, conf=0.84)

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  • The most important feature for diet modification is a reduced-calorie meal plan, which is essential for effective weight loss.

    “The most important feature for diet modification is a reduced-calorie meal plan, which is essential for effective weight loss.687–690”

    From American Association of Clinical Endocrinology Clinical Practice Guideline: Developing a Diabetes Mellitus Comprehensive Care Plan-2022 Update. (2022) · cites this paper as [690]

    The Low-Carbohydrate Diet section describes a plan with no limit on total calories. The Results report weight loss on that plan, and the Discussion calls it an effective alternative for people who will not follow a restricted-calorie regimen. Although participants in all groups achieved a caloric deficit, the paper does not support the claim that a reduced-calorie meal plan is essential. (LLM, conf=0.88)

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  • Intensive lifestyle intervention in the Look AHEAD trial resulted in 1-year weight loss of 8.6% and 4-year weight loss of 4.7%, compared with 1.1% in the standard group.

    “Intensive lifestyle intervention resulted in 1-year weight loss of 8.6%, and 4-year weight loss of 4.7% compared with 1.1% in the standard group, and was accompanied by lower A1C with less need for DM medications, DM remission in ~10% of persons, lower diastolic and systolic BP, improved lipids (higher HDL-C, lower triglycerides), improvements in OSA as reflected by lower apnea hypopnea index sc”

    From American Association of Clinical Endocrinology Clinical Practice Guideline: Developing a Diabetes Mellitus Comprehensive Care Plan-2022 Update. (2022) · cites this paper as [690]

    The Abstract and Weight Loss section describe a two-year trial comparing three diets, not the Look AHEAD trial. The Weight Loss section reports weight changes in kilograms at 24 months; it does not report the claimed one- and four-year percentages or a standard-group comparison. Page numbers are unavailable in our copy. (LLM, conf=0.88)

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  • Short-term trials comparing low-carbohydrate, high-protein diets with conventional high-carbohydrate, low-fat diets have yielded inconsistent results.

    “Several trials showed that low-carbohydrate, high-protein diets resulted in more weight loss over the course of 3 to 6 months than conventional high-carbohydrate, low-fat diets,4–12 but other studies did not show this effect.13–17”

    From Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates (2009) · cites this paper as [12]

    The Weight Loss section reports that weight loss was greatest during months 1–6 and was greater in the low-carbohydrate group than in the low-fat group. This supports one outcome described in the citing sentence, but this paper does not establish that short-term trials yielded inconsistent results or that its own trial failed to show the effect. Page numbers are unavailable in our copy. (LLM, conf=0.76)

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  • The trial did not confirm earlier findings that low-carbohydrate or high-protein diets caused greater weight loss at six months and that this advantage eroded by twelve months.

    “We did not confirm previous findings that low-carbohydrate or high-protein diets caused increased weight loss at 6 months3–12 and that the advantage of these diets usually eroded by 12 months, with weight loss that was nearly or fully equivalent to that with low-fat diets6,11,18 or other diets.12”

    From Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates (2009) · cites this paper as [12]

    The Weight Loss section reports greater weight loss with the low-carbohydrate diet than with the low-fat diet, consistent with an early advantage. It does not establish that this advantage eroded to near-equivalence by 12 months; it reports greater low-carbohydrate weight loss at 24 months. The citing authors’ statement that they ‘did not confirm’ earlier findings describes their own trial, not Shai et al.’s. (LLM, conf=0.84)

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Research works printed but not linked: 1

  1. [1]1. Obesity: preventing and managing 1. the global epidemic: report of a WHO consultation. World Health Organ Tech Rep Ser 2000;894:1-253.

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Authors
Shai, I., Schwarzfuchs, D., Henkin, Y., Shahar, D. R., Witkow, S., Greenberg, I., Golan, R., Fraser, D., Bolotin, A., Vardi, H., Tangi-Rozental, O., Zuk-Ramot, R., Sarusi, B., Brickner, D., Schwartz, Z., Sheiner, E., Marko, R., Katorza, E., Thiery, J., Fiedler, G. M., Blüher, M., Stumvoll, M., & Stampfer, M. J.
Affiliations
  • Ben-Gurion University of the Negev (IL)
  • Shimon Peres Negev Nuclear Research Center (IL)
  • Soroka Medical Center (IL)
  • University Hospital Leipzig (DE)
  • Leipzig University (DE)
  • Harvard University (US)
Venue
New England Journal of Medicine
Published
2008-07-17
Volume
359
Issue
3
Pages
229-241
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
OpenAlex
W2146463166
Cited by
2,143
References
43
Citations by year
2026: 54 · 2025: 68 · 2024: 79 · 2023: 119 · 2022: 126 · 2021: 125 · 2020: 191 · 2019: 115 · 2018: 123 · 2017: 112 · 2016: 115 · 2015: 106 · 2014: 121 · 2013: 136 · 2012: 127
FWCI
95.74
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • IRIS eCampus Telematic University (Università degli Studi eCampus) (submittedVersion)
  • Research at the University of Copenhagen (University of Copenhagen) (submittedVersion)
Topics
  • Health Sciences › Medicine › Physiology › Diet and metabolism studies
  • Health Sciences › Medicine › Physiology › Dietary Effects on Health
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Nutritional Studies and Diet
Keywords
weight loss, Mediterranean diet, low-carbohydrate diet, low-fat diet, obesity, dietary adherence, dietary fiber, urinary ketones, TC/HDL-C ratio, glycemic control, fasting blood glucose, insulin, type 2 diabetes, dietary intervention
MeSH terms
Blood Glucose, Energy Intake, Female, Follow-Up Studies, Glycated Hemoglobin, Humans, Ketones, Lipids, Male, Middle Aged, Obesity, Surveys and Questionnaires, Biomarkers, Weight Loss, Body Mass Index, Diet, Fat-Restricted, Diet, Mediterranean, Diet, Carbohydrate-Restricted

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