The DOI matches its Crossref record; 71 of the 72 references it cites were found in a registry or an index; 9 of the 34 sources its claims cite were checked for support.
Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis
Open accessAbstract
OBJECTIVE: Few randomized clinical studies have evaluated the impact of diet and physical activity on testosterone levels in obese men with conflicting results. Conversely, studies on bariatric surgery in men generally have shown an increase in testosterone levels. The aim of this study is to perform a systematic review and meta-analysis of available trials on the effect of body weight loss on sex hormones levels. DESIGN: Meta-analysis. METHODS: An extensive Medline search was performed including the following words: 'testosterone', 'diet', 'weight loss', 'bariatric surgery', and 'males'. The search was restricted to data from January 1, 1969 up to August 31, 2012. RESULTS: Out of 266 retrieved articles, 24 were included in the study. Of the latter, 22 evaluated the effect of diet or bariatric surgery, whereas two compared diet and bariatric surgery. Overall, both a low-calorie diet and bariatric surgery are associated with a significant (P<0.0001) increase in plasma sex hormone-binding globulin-bound and -unbound testosterone levels (total testosterone (TT)), with bariatric surgery being more effective in comparison with the low-calorie diet (TT increase: 8.73 (6.51-10.95) vs 2.87 (1.68-4.07) for bariatric surgery and the low-calorie diet, respectively; both P<0.0001 vs baseline). Androgen rise is greater in those patients who lose more weight as well as in younger, non-diabetic subjects with a greater degree of obesity. Body weight loss is also associated with a decrease in estradiol and an increase in gonadotropins levels. Multiple regression analysis shows that the degree of body weight loss is the best determinant of TT rise (B=2.50±0.98, P=0.029). CONCLUSIONS: These data show that weight loss is associated with an increase in both bound and unbound testosterone levels. The normalization of sex hormones induced by body weight loss is a possible mechanism contributing to the beneficial effects of surgery in morbid obesity.
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32 Own result · 7 Own method · 7 Own interpretation · 6 No full text of the sources · 5 Partly supported · 3 Supported so far · 3 No basis given · 2 Sources not found · accuracy not yet measured
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In the paper
“However, it is important to note that an increased BMI was associated with a low measured, or calculated, free and bioavailable testosterone (24).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Introduction
What the sources say
- Partly supportedcites [24] 24. Saad F, Aversa A, Isidori AM & Gooren LJ. Testosterone as potential effective therapy in treatment of obesity in men with testosterone deficiency: a review. Current Diabetes Reviews 2012 8 131-143. (doi:10.2174/157339912799424573) sourceExperimental — accuracy not yet measured
The 'Relationship Between Testosterone and Obesity' section reports an inverse relationship between BMI and testosterone levels in men. It does not specify that this BMI association holds for measured or calculated free and bioavailable testosterone; its separate discussion of free and bioavailable testosterone concerns diabetes risk, not BMI. Page numbers were not available in our copy. (LLM, conf=0.84)
plaincorrelational- Asserted: passes — The authors put it forward as true.
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- Partly supported
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Accordingly, patients with T2DM and insulin resistance show a higher prevalence of hypogonadotropic hypogonadism (54,55,60)”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [54] 54. Dhindsa S, Prabhakar S, Sethi M, Bandyopadhyay A, Chaudhuri A & Dandona P. Frequent occurrence of hypogonadotropic hypogo- nadism in type 2 diabetes. Journal of Clinical Endocrinology and Metabolism 2004 89 5462-5468. (doi:10.1210/jc.2004- 0804) source
- Supportedcites [55] 55. Dandona P & Dhindsa S. Update: hypogonadotropic hypogonadism in type 2 diabetes and obesity. Journal of Clinical Endocrinology and Metabolism 2011 96 2643-2651. (doi:10.1210/jc.2010- 2724) source
The passage headed Abstract reports that hypogonadotropic hypogonadism is present in 25–40% of men with type 2 diabetes. Another passage headed Abstract says it is probably related to insulin resistance, supporting the citing sentence’s association without establishing insulin resistance as a cause. (LLM, conf=0.90)
- Not checked — no full text of the sourcecites [60] 60. Corona G, Mannucci M, Petrone L, Ricca V, Balercia G, Mansani R, Chiarini V, Giommi R, Forti G & Maggi M. Association of hypogonadism and type 2 diabetes in men attending an outpatient erectile dysfunction clinic. International Journal of Impotence Research 2006 18 190-197. (doi:10.1038/sj.ijir.3901391) source
plaincorrelational- Asserted: passes — The authors put it forward as true.
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The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“An obesityassociated decline in SHBG might partially explain the observed fall in testosterone levels (19,20,21,22,23).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Introduction
What the sources say
- Not checked — no full text of the sourcecites [19] 19. Corona G, Rastrelli G, Vignozzi L & Maggi M. Emerging medication for the treatment of male hypogonadism. Expert Opinion on Emerging Drugs 2012 17 239-592. (doi:10.1517/14728214. 2012.683411) source
- Partly supportedcites [20] 20. Corona G, Rastrelli G, Vignozzi L, Mannucci E & Maggi M. How to recognize late-onset hypogonadism in men with sexual dysfunc- tion. Asian Journal of Andrology 2012 14 251-259. (doi:10.1038/ aja.2011.138) sourceExperimental — accuracy not yet measured
The classification section says SHBG can be decreased in obesity and recommends considering free testosterone measurement in that setting. The Abstract reports that waist circumference helps detect low testosterone, but the paper does not explicitly say that reduced SHBG explains the fall in testosterone levels. (LLM, conf=0.82)
- Not checked — no full text of the sourcecites [21] 21. Corona G, Rastrelli G, Morelli A, Vignozzi L, Mannucci E & Maggi M. Hypogonadism and metabolic syndrome. Journal of Endocrinological Investigation 2011 34 557-567. source
- Not checked — no full text of the sourcecites [22] 22. Corona G, Mannucci E, Forti G & Maggi M. Following the common association between testosterone deficiency and diabetes mellitus, can testosterone be regarded as a new therapy for diabetes? International Journal of Andrology 2009 32 431-441. (doi:10.1111/j.1365-2605.2009.00965.x) source
- Not checked — no full text of the sourcecites [23] 23. Wu FC, Tajar A, Pye SR, Silman AJ, Finn JD, O'Neill TW, Bartfai G, Casanueva F, Forti G, Giwercman A et al. Hypothalamic-pituitary- testicular axis disruptions in older men are differentially linked to age and modifiable risk factors: the European Male Aging Study. Journal of Clinical Endocrinology and Metabolism 2008 93 2737-2745. (doi:10.1210/jc.2007-1972) source
hedgedconditional- Asserted: passes — The authors put it forward as true.
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- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
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The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Based on these and other studies (53,54), obesity-related male hypogonadism is now considered as a form of hypogonadotropic hypogonadism (see for a review, references (55,56)).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [53] 53. Corona G, Mannucci E, Fisher AD, Lotti F, Petrone L, Balercia G, Bandini E, Forti G & Maggi M. Low levels of androgens in men with erectile dysfunction and obesity. Journal of Sexual Medicine 2008 5 2454-2463. source
- Not checked — no full text of the sourcecites [54] 54. Dhindsa S, Prabhakar S, Sethi M, Bandyopadhyay A, Chaudhuri A & Dandona P. Frequent occurrence of hypogonadotropic hypogo- nadism in type 2 diabetes. Journal of Clinical Endocrinology and Metabolism 2004 89 5462-5468. (doi:10.1210/jc.2004- 0804) source
- Supportedcites [55] 55. Dandona P & Dhindsa S. Update: hypogonadotropic hypogonadism in type 2 diabetes and obesity. Journal of Clinical Endocrinology and Metabolism 2011 96 2643-2651. (doi:10.1210/jc.2010- 2724) source
The passage headed “What Comes First: Hypogonadism or Type 2 Diabetes?” says that obesity is associated with hypogonadotropic hypogonadism (HH). The preceding discussion also identifies the primary defect in obesity-related hypogonadism as hypothalamo-hypophyseal, consistent with that classification. (LLM, conf=0.92)
- Could not verifycites [56] 56. Saad F, Aversa A, Isidori AM, Zafalon L, Zitzmann M & Gooren L. Onset of effects of testosterone treatment and time span until maximum effects are achieved. European Journal of Endocrinology 2011 165 675-685. (doi:10.1530/EJE-11-0221) sourceExperimental — accuracy not yet measured
The Discussion addresses testosterone treatment, visceral obesity and metabolic syndrome, but does not classify obesity-related male hypogonadism as hypogonadotropic. Searches for that classification and for “hypogonadotropic” found the term only in titles in the References, not a passage making the claimed connection; page numbers were unavailable in our copy. (LLM, conf=0.74)
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“The increased amount of estrogen levels might, in turn, play a negative feedback on both the hypothalamus and the pituitary, leading to decreased LH secretion (22,55).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [22] 22. Corona G, Mannucci E, Forti G & Maggi M. Following the common association between testosterone deficiency and diabetes mellitus, can testosterone be regarded as a new therapy for diabetes? International Journal of Andrology 2009 32 431-441. (doi:10.1111/j.1365-2605.2009.00965.x) source
- Partly supportedcites [55] 55. Dandona P & Dhindsa S. Update: hypogonadotropic hypogonadism in type 2 diabetes and obesity. Journal of Clinical Endocrinology and Metabolism 2011 96 2643-2651. (doi:10.1210/jc.2010- 2724) sourceExperimental — accuracy not yet measured
The Abstract describes a hypothesis that excess estrogen in obesity may suppress hypothalamic GnRH secretion, which could account for reduced LH. It does not attribute estrogen feedback to the pituitary, and it reports that lower estradiol in men with diabetic hypogonadotropic hypogonadism argues against this mechanism as their explanation. (LLM, conf=0.86)
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
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- Based: passes — The paper gives a reason why it holds.
The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“Our knowledge of the long-term effects of bariatric surgery is based only on observational, non-randomized studies, often of poor methodological quality.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not matchedcites [64] 64. Sjo ¨stro ¨m L, Narbro K, Sjo ¨stro ¨m CD, Karason K, Larsson B, Wedel H, Lystig T, Sullivan M, Bouchard C, Carlsson B et al. Effects of bariatric surgery on mortality in Swedish obese subjects. New England Journal of Medicine 2007 357 741-752. (doi:10.1056/ NEJMoa066254)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Partly supportedcites [65] 65. Sjo ¨stro ¨m L, Lindroos AK, Peltonen M, Torgerson J, Bouchard C, Carlsson B, Dahlgren S, Larsson B, Narbro K, Sjo ¨stro ¨m CD et al. Lifestyle, diabetes, and cardiovascular risk factors 10 years after bariatric surgery. New England Journal of Medicine 2004 351 2683-2693. (doi:10.1056/NEJMoa035622) sourceExperimental — accuracy not yet measured
The Study Design section (page not provided) describes the SOS study as a prospective, nonrandomized intervention trial, and the discussion (under “death and other adverse events”; page not provided) says its main limitation was the lack of randomization. These passages support the concern about nonrandomized long-term evidence, but the paper does not say that such studies were often of poor methodological quality or that the evidence consisted only of observational studies. (LLM, conf=0.83)
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
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- Not matched
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“When considering data on E 2 , body weight loss was associated with a significant reduction in plasma E 2 (mean changes K8.87 (K15.22;K2.52)pmol/l, P!0.0001; Fig. 4A).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Study Location
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In particular, malabsorptive surgery (including studies which performed biliopancreatic diversion, see references (35,43,44,46,50)) determined a more consistent increase in TT when compared with non-malabsorptive surgery (including studies which performed gastroplasty approach, see references (41, 42)) (11.58 (7.12-16.03)vs 6.08 (2.38-9.78)nmol/l, respectively; both P!0.0001).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Effect of Diet or bariatric surgery on hormonal modifications
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Similar to what was observed for TT, SHBG (P!0.0001) and cFT levels significantly increased after body weight loss (P!0.0001; see also Fig. 2B and C).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Study Location
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Finally, body weight loss, whatever obtained, was significantly associated with a significant increase in both LH and FSH levels (1.31 (0.80-1.82) and 1.79 (1.28-2.30)U/l for LH and FSH, respectively; both P!0.0001, see also Fig. 5A and B).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Study Location
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- It may state two separate claims as one. 14
- Probably not a substantial claim. 10
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“It is known that obesity in men is associated with low testosterone and reduced sex hormone-binding globulin (SHBG) levels (19,20,21,22,23).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Introduction
What the sources say
- Not checked — no full text of the sourcecites [19] 19. Corona G, Rastrelli G, Vignozzi L & Maggi M. Emerging medication for the treatment of male hypogonadism. Expert Opinion on Emerging Drugs 2012 17 239-592. (doi:10.1517/14728214. 2012.683411) source
- Supportedcites [20] 20. Corona G, Rastrelli G, Vignozzi L, Mannucci E & Maggi M. How to recognize late-onset hypogonadism in men with sexual dysfunc- tion. Asian Journal of Andrology 2012 14 251-259. (doi:10.1038/ aja.2011.138) source
In the section on recognizing late-onset hypogonadism, the paper reports that increased waist circumference was associated with low testosterone in men seeking care for sexual dysfunction. In its classification section, it also identifies obesity as a condition in which sex hormone-binding globulin can be decreased. The wording about SHBG is qualified as a possibility, rather than an inevitable effect. (LLM, conf=0.85)
- Not checked — no full text of the sourcecites [21] 21. Corona G, Rastrelli G, Morelli A, Vignozzi L, Mannucci E & Maggi M. Hypogonadism and metabolic syndrome. Journal of Endocrinological Investigation 2011 34 557-567. source
- Not checked — no full text of the sourcecites [22] 22. Corona G, Mannucci E, Forti G & Maggi M. Following the common association between testosterone deficiency and diabetes mellitus, can testosterone be regarded as a new therapy for diabetes? International Journal of Andrology 2009 32 431-441. (doi:10.1111/j.1365-2605.2009.00965.x) source
- Not checked — no full text of the sourcecites [23] 23. Wu FC, Tajar A, Pye SR, Silman AJ, Finn JD, O'Neill TW, Bartfai G, Casanueva F, Forti G, Giwercman A et al. Hypothalamic-pituitary- testicular axis disruptions in older men are differentially linked to age and modifiable risk factors: the European Male Aging Study. Journal of Clinical Endocrinology and Metabolism 2008 93 2737-2745. (doi:10.1210/jc.2007-1972) source
boostedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“These studies showed a relevant beneficial effect of surgery on body weight loss, survival, and obesity-related comorbidities (64, 65).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [64] 64. Sjo ¨stro ¨m L, Narbro K, Sjo ¨stro ¨m CD, Karason K, Larsson B, Wedel H, Lystig T, Sullivan M, Bouchard C, Carlsson B et al. Effects of bariatric surgery on mortality in Swedish obese subjects. New England Journal of Medicine 2007 357 741-752. (doi:10.1056/ NEJMoa066254) source
- Partly supportedcites [65] 65. Sjo ¨stro ¨m L, Lindroos AK, Peltonen M, Torgerson J, Bouchard C, Carlsson B, Dahlgren S, Larsson B, Narbro K, Sjo ¨stro ¨m CD et al. Lifestyle, diabetes, and cardiovascular risk factors 10 years after bariatric surgery. New England Journal of Medicine 2004 351 2683-2693. (doi:10.1056/NEJMoa035622) sourceExperimental — accuracy not yet measured
The Abstract reports substantial long-term weight loss and improvements in several obesity-related risk factors after surgery, though not all risk factors improved. The “death and other adverse events” section says mortality analyses were still ongoing, so this paper does not establish a survival benefit. (LLM, conf=0.91)
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Out of 266 retrieved articles, 24 were included in the study.”
- Also stated in: § Results · plain
“Out of 266 retrieved articles, 24 were included in the study.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Abstract Objective: Few randomized clinical studies have evaluated the impact of diet and physical activity on testosterone levels in obese men with conflicting results.Conversely, studies on bariatric surgery in men generally have shown an increase in testosterone levels.The aim of this study is to perform a systematic review and meta-analysis of available trials on the effect of body weight loss on sex hormones levels.Design: Meta-analysis.Methods: An extensive Medline search was performed including the following words: 'testosterone', 'diet', 'weight loss', 'bariatric surgery', and 'males'.The search was restricted to data from January 1, 1969 up to August 31, 2012.Results: Out of 266 retrieved articles, 24 were included in the study.Of the latter, 22 evaluated the effect of diet or bariatric surgery, whereas two compared diet and bariatric surgery.Overall, both a lowcalorie diet and bariatric surgery are associated with a significant (P!0.0001) increase in plasma sex hormone-binding globulin-bound and -unbound testosterone levels (total testosterone (TT)), with bariatric surgery being more effective in comparison with the low-calorie diet (TT increase: 8.73 (6.51-10.95)vs 2.87 (1.68-4.07)for bariatric surgery and the low-calorie diet, respectively; both P!0.0001 vs baseline).Androgen rise is greater in those patients who lose more weight as well as in younger, non-diabetic subjects with a greater degree of obesity.Body weight loss is also associated with a decrease in estradiol and an increase in gonadotropins levels.Multiple regression analysis shows that the degree of body weight loss is the best determinant of TT rise (BZ2.50G0.98,PZ0.029).Conclusions: These data show that weight loss is associated with an increase in both bound and unbound testosterone levels.The normalization of sex hormones induced by body weight loss is a possible mechanism contributing to the beneficial effects of surgery in morbid obesity.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
- Also stated in: § Results · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“with bariatric surgery being more effective in comparison with the low-calorie diet (TT increase: 8.73 (6.51-10.95)vs 2.87 (1.68-4.07)for bariatric surgery and the low-calorie diet, respectively; both P!0.0001 vs baseline).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Abstract Objective: Few randomized clinical studies have evaluated the impact of diet and physical activity on testosterone levels in obese men with conflicting results.Conversely, studies on bariatric surgery in men generally have shown an increase in testosterone levels.The aim of this study is to perform a systematic review and meta-analysis of available trials on the effect of body weight loss on sex hormones levels.Design: Meta-analysis.Methods: An extensive Medline search was performed including the following words: 'testosterone', 'diet', 'weight loss', 'bariatric surgery', and 'males'.The search was restricted to data from January 1, 1969 up to August 31, 2012.Results: Out of 266 retrieved articles, 24 were included in the study.Of the latter, 22 evaluated the effect of diet or bariatric surgery, whereas two compared diet and bariatric surgery.Overall, both a lowcalorie diet and bariatric surgery are associated with a significant (P!0.0001) increase in plasma sex hormone-binding globulin-bound and -unbound testosterone levels (total testosterone (TT)), with bariatric surgery being more effective in comparison with the low-calorie diet (TT increase: 8.73 (6.51-10.95)vs 2.87 (1.68-4.07)for bariatric surgery and the low-calorie diet, respectively; both P!0.0001 vs baseline).Androgen rise is greater in those patients who lose more weight as well as in younger, non-diabetic subjects with a greater degree of obesity.Body weight loss is also associated with a decrease in estradiol and an increase in gonadotropins levels.Multiple regression analysis shows that the degree of body weight loss is the best determinant of TT rise (BZ2.50G0.98,PZ0.029).Conclusions: These data show that weight loss is associated with an increase in both bound and unbound testosterone levels.The normalization of sex hormones induced by body weight loss is a possible mechanism contributing to the beneficial effects of surgery in morbid obesity.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Of the latter, 22 evaluated the effect of diet or bariatric surgery, whereas two compared diet and bariatric surgery.”
- Also stated in: § Results · plain
“Of the included studies (see the trial flow summary in Fig. 1), 22 evaluated the effect of diet or bariatric surgery, whereas two compared diet and bariatric surgery.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Abstract Objective: Few randomized clinical studies have evaluated the impact of diet and physical activity on testosterone levels in obese men with conflicting results.Conversely, studies on bariatric surgery in men generally have shown an increase in testosterone levels.The aim of this study is to perform a systematic review and meta-analysis of available trials on the effect of body weight loss on sex hormones levels.Design: Meta-analysis.Methods: An extensive Medline search was performed including the following words: 'testosterone', 'diet', 'weight loss', 'bariatric surgery', and 'males'.The search was restricted to data from January 1, 1969 up to August 31, 2012.Results: Out of 266 retrieved articles, 24 were included in the study.Of the latter, 22 evaluated the effect of diet or bariatric surgery, whereas two compared diet and bariatric surgery.Overall, both a lowcalorie diet and bariatric surgery are associated with a significant (P!0.0001) increase in plasma sex hormone-binding globulin-bound and -unbound testosterone levels (total testosterone (TT)), with bariatric surgery being more effective in comparison with the low-calorie diet (TT increase: 8.73 (6.51-10.95)vs 2.87 (1.68-4.07)for bariatric surgery and the low-calorie diet, respectively; both P!0.0001 vs baseline).Androgen rise is greater in those patients who lose more weight as well as in younger, non-diabetic subjects with a greater degree of obesity.Body weight loss is also associated with a decrease in estradiol and an increase in gonadotropins levels.Multiple regression analysis shows that the degree of body weight loss is the best determinant of TT rise (BZ2.50G0.98,PZ0.029).Conclusions: These data show that weight loss is associated with an increase in both bound and unbound testosterone levels.The normalization of sex hormones induced by body weight loss is a possible mechanism contributing to the beneficial effects of surgery in morbid obesity.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Also stated in: § Results · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Baseline TT, BMI, and D-BMI as well as the percent increase in SHBG (D-SHBG) were all significantly associated with D-TT (BZ5.16G2.13,PZ0.022; BZ2.51G0.84,PZ0.007; BZ2.76G0.71,PZ0.001; and BZ0.70G 0.24, PZ0.013 respectively), whereas no association between D-TT and D-E 2 or DM at baseline was observed after adjusting for age (data not shown).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Effect of Diet or bariatric surgery on hormonal modifications
plaincorrelational- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“Furthermore, a reduction in body weight is associated with an increase in SHBG, cFT, LH, and FSH and a reduction in E 2 .”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“However, the testosterone rise induced by lifestyle interventions was only modest, probably reflecting the relatively modest results of the targeted diet and physical activity on body weight loss (9.8% with diet vs 32% with surgery in the studies included in this meta-analysis).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Interestingly, we now report that the diabetic condition has a negative effect on testosterone rise after the intervention; however, this difference does not retain statistical significance after adjusting for D-BMI, suggesting that it could be due to a greater body weight loss in non-diabetic patients.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“The quality of studies was assessed using the Cochrane criteria (49).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Materials and methods
What the sources say
- Not matchedcites [49] 49. The Cochrane Collaboration, 2008. (Available from www. cochrane-handbook.org).
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“The identification of relevant abstracts, the selection of studies based on the criteria described above, and the subsequent data extraction were performed independently by two of the authors (G Corona and G Rastrelli), and conflicts resolved by the third investigator (M Monami).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Materials and methods
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Completed but still unpublished trials were identified through a search of the www.clinicaltrials.govwebsite and the results, when not already available on the website, were obtained through a formal request to the authors.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Materials and methods
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The beneficial effects of body weight loss are more apparent in younger, nondiabetic subjects with a greater degree of obesity; however, this could be due to a greater body weight loss.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“In line with this data, the Endocrine Society Guidelines (62) and the Third International Consultation on Sexual Medicine (63) emphasized that lifestyle modifications should be strongly encouraged in hypogonadal subjects with obesity, T2DM, and the MetS.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [62] 62. Bhasin S, Cunningham GR, Hayes FJ, Matsumoto AM, Snyder PJ, Swerdloff RS, Montori VM, Task Force & Endocrine Society. Testosterone therapy in men with androgen deficiency syndromes: an Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology and Metabolism 2010 95 2536-2559. (doi:10.1210/jc.2009-2354) source
- Not checked — no full text of the sourcecites [63] 63. Buvat J, Maggi M, Gooren L, Guay AT, Kaufman J, Morgentaler A, Schulman C, Tan HM, Torres LO, Yassin A et al. Endocrine aspects of male sexual dysfunctions. Journal of Sexual Medicine 2010 7 (4 Pt 2) 1627-1656. (doi:10.1111/j.1743-6109.2010.01780.x) source
boosted- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Similarly, an 18-week, placebocontrolled RCT in obese patients with obstructive sleep apnea demonstrated that the combination of TRT and lifestyle modifications improved insulin sensitivity, reduced liver fat, and increased muscle mass in comparison with placebo and lifestyle modifications alone (69).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [69] 69. Hoyos CM, Yee BJ, Phillips CL, Machan EA, Grunstein RR & Liu PY. Body compositional and cardiometabolic effects of testosterone therapy in obese men with severe obstructive sleep apnea: a randomised placebo-controlled trial. European Journal of Endo- crinology 2012 167 531-541. (doi:10.1530/EJE-12-0525) source
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Evidence indicates that testosterone deficiency induces increased adiposity while increased adiposity induces hypogonadism (22,25).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Introduction
What the sources say
- Not checked — no full text of the sourcecites [22] 22. Corona G, Mannucci E, Forti G & Maggi M. Following the common association between testosterone deficiency and diabetes mellitus, can testosterone be regarded as a new therapy for diabetes? International Journal of Andrology 2009 32 431-441. (doi:10.1111/j.1365-2605.2009.00965.x) source
- Not checked — no full text of the sourcecites [25] 25. Stanik S, Dornfeld LP, Maxwell MH, Viosca SP & Korenman SG. The effect of weight loss on reproductive hormones in obese men. Journal of Clinical Endocrinology and Metabolism 1981 53 828-832. (doi:10.1210/jcem-53-4-828) source
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“Accordingly, it has been reported that a weekly low dose (2.5 mg) of the aromatase inhibitor letrozole can restore testosterone levels and increase LH levels in severely obese hypogonadal men (57).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [57] 57. Loves S, Ruinemans-Koerts J & de Boer H. Letrozole once a week normalizes serum testosterone in obesity-related male hypogonad- ism. European Journal of Endocrinology 2008 158 741-747. (doi:10.1530/EJE-07-0663) source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“First, hormonal assays and reference values were not often comparable.”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“An alternative possibility is that weight reduction is associated with increased insulin sensitivity, with insulin having a permissive role on GnRH neuron activity (59).”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
What the sources say
- Not checked — no full text of the sourcecites [59] 59. Burcelin R, Thorens B, Glauser M, Gaillard RC & Pralong FP. Gonadotropin-releasing hormone secretion from hypothalamic neurons: stimulation by insulin and potentiation by leptin. Endocrinology 2003 144 4484-4491. (doi:10.1210/en.2003-0457) source
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
The paper relies on this without support.
Most studies that did not describe P values reported a non-significant difference across groups.
“Given that most of the studies that did not describe P values reported a non-significant difference across groups, the mean (paired) analysis, which excludes these data, is likely to overestimate the effect of treatments.”
The paper relies on this without support.
Obesity is characterized by a relative abundance of estrogens because P450 aromatase is highly expressed by fat tissue.
“Obesity is characterized by a relative abundance of estrogens since P450 aromatase is highly expressed by fat tissue.”
The paper relies on this without support.
Male hypogonadism is one of the many adverse consequences of overweight and obesity.
“Male hypogonadism can be considered as one of the many adverse consequences of overweight and obesity.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The cited source says what the claim attributes to it.
In the citing paper
“Both bariatric surgery and a low-calorie diet were associated with a significant increase in testosterone levels, however the effect was more pronounced for bariatric surgery than for the low-calorie diet.”
From Treatment of Men with Central Hypogonadism: Alternatives for Testosterone Replacement Therapy (2020) · cites this paper as [21]
The cited source says what the claim attributes to it.
In the citing paper
“The magnitude of increase in testosterone levels was associated with the amount of weight loss [21].”
From Treatment of Men with Central Hypogonadism: Alternatives for Testosterone Replacement Therapy (2020) · cites this paper as [21]
The cited source says what the claim attributes to it.
In the citing paper
“Both bariatric surgery and a low-calorie diet were associated with a significant increase in testosterone levels, however the effect was more pronounced for bariatric surgery than for the low-calorie diet.”
From Treatment of Men with Central Hypogonadism: Alternatives for Testosterone Replacement Therapy (2020) · cites this paper as [21]
In the citing paper
“Genetic heritability likely accounts for a significant portion of mean T levels in a select population as well as observed diurnal variations.”
From Challenges in Testosterone Measurement, Data Interpretation, and Methodological Appraisal of Interventional Trials (2016) · cites this paper as [56]
In the citing paper
“Results of adult males have confirmed similar findings, with genetic contribution towards T variability of 42–65%.”
From Challenges in Testosterone Measurement, Data Interpretation, and Methodological Appraisal of Interventional Trials (2016) · cites this paper as [56]
In the citing paper
“The authors concluded that weight loss is associated with an increase on TT and free Testosterone levels and that bariatric surgery is more effective compared to a low-calorie diet on the hormonal profile.”
From MOSH Syndrome (Male Obesity Secondary Hypogonadism): Clinical Assessment and Possible Therapeutic Approaches (2018) · cites this paper as [47]
In the citing paper
“The authors concluded that weight loss is associated with an increase on TT and free Testosterone levels and that bariatric surgery is more effective compared to a low-calorie diet on the hormonal profile.”
From MOSH Syndrome (Male Obesity Secondary Hypogonadism): Clinical Assessment and Possible Therapeutic Approaches (2018) · cites this paper as [47]
In the citing paper
“This evidence of a causative effect of BMI on serum T is supported by a recent meta-analysis of the impact of body weight reduction on serum T, revealing that body weight reductions as a result of both low-calorie diet and bariatric surgery are associated with significantly increased serum T [37].”
From Causal relationship between obesity and serum testosterone status in men: A bi-directional mendelian randomization analysis (2017) · cites this paper as [37]
In the citing paper
“Not only serum T but also the gonadotropins FSH and LH were increased by body weight reduction, suggesting that body weight loss reverses obesity-associated hypogonadotropic hypogonadism [37].”
From Causal relationship between obesity and serum testosterone status in men: A bi-directional mendelian randomization analysis (2017) · cites this paper as [37]
In the citing paper
“Notably, this meta-analysis demonstrated that the degree of body weight loss is a robust determinant of the increase in serum T.”
From Causal relationship between obesity and serum testosterone status in men: A bi-directional mendelian randomization analysis (2017) · cites this paper as [37]
In the citing paper
“The mean percent body weight loss at endpoint was 10% in low-calorie diet studies and 32% in bariatric surgery studies and the corresponding increases in serum T levels were 0.83 ng/ml and 2.54 ng/ml, respectively.”
From Causal relationship between obesity and serum testosterone status in men: A bi-directional mendelian randomization analysis (2017) · cites this paper as [37]
In the citing paper
“We found that an average diet-induced weight loss of 9.8% was associated with a significant increase in total T (TT) of 2.8 nmol/L (1.68–4.07 nmol/L) and 2.05 (0.93–3.16 nmol/L), when paired and non-paired t-test models were applied.”
From Treatment of Functional Hypogonadism Besides Pharmacological Substitution (2020) · cites this paper as [23]
In the citing paper
“However, when data from diet were combined with those from bariatric surgery (see below), we reported a significant weight loss-induced increase in luteinizing hormone (LH) (1.31 mU/L [0.80–1.82 mU/L]) and follicle stimulating hormone (1.79 mU/L [1.28–2.30 mU/L]) [23].”
From Treatment of Functional Hypogonadism Besides Pharmacological Substitution (2020) · cites this paper as [23]
In the citing paper
“While exact mechanisms are unknown, the reversal of HPT axis suppression with weight loss 43,46,47 suggests a pathogenic role for excess adipose tissue.”
From Hypogonadism and male obesity: Focus on unresolved questions (2018) · cites this paper as [47]
In the citing paper
“Bariatric surgery is associated with an increase in total testosterone of 8.73 nmol/L [6.51-10.95]together with increases in gonadotropins and free testosterone, suggesting a genuine reactivation of the HPT axis.47”
From Hypogonadism and male obesity: Focus on unresolved questions (2018) · cites this paper as [47]
In the citing paper
“In a meta-analysis, diet-associated weight loss (mean 9.8%) increased testosterone by 2.9 nmol/L (84 ng/dL) and surgical weight loss (32%) by 8.7 nmol/L (251 ng/dL) (21).”
From A Perspective on Middle-Aged and Older Men With Functional Hypogonadism: Focus on Holistic Management (2017) · cites this paper as [21]
In the citing paper
“However, this meta-analysis was limited to small studies (total < 500 patients) with short-term follow-up and heterogeneous study designs (21).”
From A Perspective on Middle-Aged and Older Men With Functional Hypogonadism: Focus on Holistic Management (2017) · cites this paper as [21]
In the citing paper
“30% of weight loss after bariatric surgery with the increase of total testosterone by 8.7 nmol/L (3, 20, 22)”
From Effects of liraglutide on obesity-associated functional hypogonadism in men (2019) · cites this paper as [3]
In the citing paper
“Its impact was generally related to the magnitude of WR.”
From Effects of liraglutide on obesity-associated functional hypogonadism in men (2019) · cites this paper as [3]
In the citing paper
“The impact of WR on testosterone level in obese men has been evaluated only in few RCT and meta-analysis that was limited to small studies with short-term follow-up and heterogeneous study designs (3, 20).”
From Effects of liraglutide on obesity-associated functional hypogonadism in men (2019) · cites this paper as [3]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Rated major: it would touch a result — a value a result rests on, reported and recomputed p-values on opposite sides of the significance level, two passages that conflict with no sign which is right, or a cited work retracted before this paper was published.
In the paper
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Study Location
“mean changes K8.87 (K15.22;K2.52)pmol/l, P!0.0001; Fig. 4A”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
“-6.50 -10.0 -3.0 0.0 -6.54 -10.4 -2.7 0.0 Differences in mean LL, 95% CI UL, 95% CI P”
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
“S: 0.43 (0.37; 0.49), P< 0.0001 I: -12.58 (-14.76;10.39), P< 0.0001”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
Reported -12.58 · recomputed -2.185
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Study Location
“1.31 (0.80-1.82) and 1.79 (1.28-2.30)U/l for LH and FSH, respectively”
§ Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis > Discussion
“0.98 0.12 1.84 0.03 1.33 0.75 1.91 0.00 A”
Citations
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Metadata
- Authors
- Corona, G., Rastrelli, G., Monami, M., Saad, F., Luconi, M., Lucchese, M., Facchiano, E., Sforza, A., Forti, G., Mannucci, E., & Maggi, M.
- Affiliations
- Azienda USL di Bologna (IT)
- University of Florence (IT)
- Azienda Ospedaliero-Universitaria Careggi (IT)
- Corresponding author
- Maggi, Mario
- ORCID
- Venue
- European Journal of Endocrinology
- Publisher
- Oxford University Press (OUP)
- Published
- 2013-06
- Volume
- 168
- Issue
- 6
- Pages
- 829-843
- ISSN
- 0804-4643 (ISSN-L)
- 1479-683X
- OpenAlex
- W2102933102
- Cited by
- 414
- References
- 72
- Citations by year
- 2026: 19 · 2025: 29 · 2024: 22 · 2023: 33 · 2022: 40 · 2021: 34 · 2020: 30 · 2019: 33 · 2018: 38 · 2017: 29 · 2016: 20 · 2015: 37 · 2014: 35 · 2013: 14
- FWCI
- 5.18
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- European Journal of Endocrinology (publishedVersion)
- PubMed (publishedVersion)
- Florence Research (University of Florence) (submittedVersion)
- Topics
- Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Hormonal and reproductive studies
- Health Sciences › Medicine › Surgery › Bariatric Surgery and Outcomes
- Health Sciences › Medicine › Reproductive Medicine › Hypothalamic control of reproductive hormones
- Keywords
- obesity, hypogonadotropic hypogonadism, testosterone, weight loss, bariatric surgery, hypocaloric diet, sex hormone-binding globulin, estradiol, gonadotropins, morbid obesity, men
- MeSH terms
- Body Weight, Humans, Hypogonadism, Obesity, Weight Loss
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