, Volume 62, Issue 3, pp 528–534 | Cite as

The effects of metformin on simple obesity: a meta-analysis

  • Hong-Hong Ning
  • Jiong Le
  • Qian Wang
  • Charlotte Aimee Young
  • Bo Deng
  • Peng-Xiang Gao
  • Hai-Qiao Zhang
  • Shu-Lan QinEmail author



To evaluate the efficacy of metformin versus a placebo in the treatment of patients with simple obesity without obesity related diseases.


A search was done on Pub-Med, EMBASE, Cochrane, and Science Citation Index Expanded databases. The main inclusion criteria included the following:(1) randomized controlled trials. (2) patients diagnosed as being overweight or obese. (3) patients were randomly assigned to receive metformin or control. Exclusion criteria included the following: patients diagnosed with an obesity related disease, such as diabetes mellitus (DM) or polycystic ovary syndrome (PCOS).


Compared with the placebo, weighted mean difference (WMD) was 2.33 (95% CI 0.31, 4.35) kg higher with metformin (p = 0.02). Compared with the placebo, WMD was 0.57 (95% CI 0.35, 0.79) kg/m² higher with metformin(p < 0.00001). There was no significant difference in the reduction of waist circumference between the metformin group and the control group (p = 0.05). The fasting blood glucose levels were significantly lower in the metformin group than in the control group (p < 0.00001). However, no hypoglycemia was noted in the metformin group or the control group.


Metformin is effective in reducing body weight of simple obesity patients, and metformin does not induce hypoglycemia as a side effect.


Metformin Obesity Overweight Weight loss Meta-analysis 



This study was funded by the health and family planning commission of jiang-xi provincial for the research of science and technology (20171964).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


  1. 1.
    T. Koca, S. Dereci, Ö. Pirgon, M. Akçam, Evaluation of the change in the prevalence of overweight and obesity in school children in South-west Turkey from 2005 to 2014. Iran. J. Public Health 47(1), 33–39 (2018)PubMedPubMedCentralGoogle Scholar
  2. 2.
    M. Jane, M. Hagger, J. Foster, S. Ho, S. Pal, Social media for health promotion and weight management: a critical debate. BMC. Public. Health 18(1), 932 (2018). CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    K. Rtveladze, T. Marsh, S. Barquera, L.M. Sanchez Romero, D. Levy, G. Melendez, L. Webber, F. Kilpi, K. Mcpherson, M. Brown, Obesity prevalence in Mexico: impact on health and economic burden. Public Health Nutr. 17(1), 233–239 (2014).;17(1):233–239 CrossRefPubMedGoogle Scholar
  4. 4.
    X. Tang, J. Li, W. Xiang, Y. Cui, B. Xie, X. Wang, Z. Xu, L. Gan, Metformin increases hepatic leptin receptor and decreases steatosis in mice. J. Endocrinol. 230(2), 227–237 (2016). CrossRefPubMedGoogle Scholar
  5. 5.
    C.J. Glueck, P. Wang, R. Fontaine, T. Tracy, L. Sieve-Smith, Metformin to restore normal menses in oligo-amenorrheic teenage girls with polycystic ovary syndrome (PCOS). J. Adolesc. Health 29(3), 160–169 (2001)CrossRefGoogle Scholar
  6. 6.
    R. Fleming, Z.E. Hopkinson, A.M. Wallace, I.A. Greer, N. Sattar, Ovarian function and metabolic factors in women with oligomenorrhea treated with metformin in a randomized double blind placebo-controlled trial. J. Clin. Endocrinol. Metab. 87(2), 569–574 (2002)CrossRefGoogle Scholar
  7. 7.
    G.A. Garinis, B. Fruci, A. Mazza, M. De Siena, S. Abenavoli, E. Gulletta, V. Ventura, M. Greco, L. Abenavoli, A. Belfiore, Metformin versus dietary treatment in nonalcoholic hepatic steatosis: a randomized study. Int. J. Obes. 34(8), 1255–1264 (2010). CrossRefGoogle Scholar
  8. 8.
    S.K. Malin, S.R. Kashyap, Effects of metformin on weight loss: potential mechanisms. Curr. Opin. Endocrinol. Diabetes Obes. 21(5), 23–329 (2014). CrossRefGoogle Scholar
  9. 9.
    D.R. Morales, A.D. Morris, Metformin in cancer treatment and prevention. Annu. Rev. Med. 66(1), 17–29 (2015). CrossRefPubMedGoogle Scholar
  10. 10.
    J.P.T. Higgins, S.G. Thompson, J.J. Deeks, D.G. Altman, Measuring inconsistency in meta-analyses. BMJ 327(7414), 557–560 (2003). CrossRefPubMedPubMedCentralGoogle Scholar
  11. 11.
    A. Golay, Metformin and body weight. Int. J. Obes. 32(1), 61–72 (2008). CrossRefGoogle Scholar
  12. 12.
    V.A. de Silva, M. Dayabandara, H. Wijesundara, T. Henegama, H. Gunewardena, C. Suraweera, R. Hanwella, Metformin for treatment of antipsychotic-induced weight gain in a South Asian population with schizophrenia or schizoaffective disorder: a double blind, randomized, placebo controlled study. J. Psychopharmacol. 29(12), 1255–1261 (2015). CrossRefPubMedGoogle Scholar
  13. 13.
    Y.W. Kim, J.Y. Kim, Y.H. Park, S.Y. Park, K.C. Won, K.H. Choi, J.Y. Huh, K.H. Moon, Metformin restores leptin sensitivity in high-fat-fed obese rats with leptin resistance. Diabetes 55(3), 716–724 (2006). CrossRefPubMedGoogle Scholar
  14. 14.
    M. Parola, F. Marra, Adipokines and redox signaling: impact on fatty liver disease. Antioxid. Redox Signal. 15(2), 461–483 (2011). CrossRefPubMedGoogle Scholar
  15. 15.
    I.S. Farooqi, S. O’Rahilly, Leptin: a pivotal regulator of human energy homeostasis. Am. J. Clin. Nutr. 89(3), 980S–984S (2009). CrossRefPubMedGoogle Scholar
  16. 16.
    N.T. Jenkins, J. Padilla, A.A. Arce-Esquivel, D.S. Bayless, J.S. Martin, H.J. Leidy, F.W. Booth, R.S. Rector, M.H. Laughlin, Effects of endurance exercise training, metformin, and their combination on adipose tissue leptin and IL-10 secretion in OLETF rats. J. Appl. Physiol. 113(12), 1873–1883 (2012). CrossRefPubMedPubMedCentralGoogle Scholar
  17. 17.
    M.P. Wróbel, B. Marek, D. Kajdaniuk, D. Rokicka, A. Szymborska-Kajanek, K. Strojek, Metformin—a new old drug. Endokrynol. Pol. 68(4), 482–496 (2017). CrossRefPubMedGoogle Scholar
  18. 18.
    A.F. Cicero, E. Tartagni, S. Ertek, Metformin and its clinical use: new insights for an old drug in clinical practice. Arch. Med. Sci. 8(5), 907–917 (2012). CrossRefPubMedPubMedCentralGoogle Scholar
  19. 19.
    J.F. Caro, Insulin resistance in obese and nonobese man. J. Clin. Endocrinol. Metab. 73(4), 691–695 (1991). CrossRefPubMedGoogle Scholar
  20. 20.
    S.A. Everson, D.E. Goldberg, S.P. Helmrich, T.A. Lakka, J.W. Lynch, G.A. Kaplan, J.T. Salonen, Weight gain and the risk of developing insulin resistance syndrome. Diabetes Care 21(10), 1637–1643 (1998)CrossRefGoogle Scholar
  21. 21.
    A. Uygun, A. Kadayifci, A.T. Isik, T. Ozgurtas, S. Deveci, A. Tuzun, Z. Yesilova, M. Gulsen, K. Dagalp, Metformin in the treatment of patients with non-alcoholic steatohepatitis. Aliment. Pharmacol. Ther. 19(5), 537–544 (2004)CrossRefGoogle Scholar
  22. 22.
    A. Fontbonne, M.A. Charles, I. Juhan-Vague, J.M. Bard, P. André, F. Isnard, J.M. Cohen, P. Grandmottet, P. Vague, M.E. Safar, E. Eschwège, The effect of metformin on the metabolic abnormalities associated with upper-body fat distribution. BIGPRO Study Group. Diabetes Care 19(9), 920–926 (1996)CrossRefGoogle Scholar
  23. 23.
    C. Rattarasarn, R. Leelawattana, S. Soonthornpun, W. Setasuban, A. Thamprasit, A. Lim, W. Chayanunnukul, N. Thamkumpee, T. Daendumrongsub, Regional abdominal fat distribution in lean and obese Thai type 2 diabetic women: relationships with insulin sensitivity and cardiovascular risk factors. Metabolism 52(11), 1444–1447 (2003)CrossRefGoogle Scholar
  24. 24.
    S.K. Praharaj, A.K. Jana, N. Goyal, V.K. Sinha, Metformin for olanzapine-induced weight gain: a systematic review and meta-analysis. Br. J. Clin. Pharmacol. 71(3), 377–382 (2011). CrossRefPubMedPubMedCentralGoogle Scholar
  25. 25.
    D.J. Siskind, J. Leung, A.W. Russell, D. Wysoczanski, S. Kisely, Metformin for clozapine associated obesity: a systematic review and meta-analysis. PLoS One 11(6), e0156208 (2016). CrossRefPubMedPubMedCentralGoogle Scholar
  26. 26.
    R. Pasquali, A. Gambineri, D. Biscotti, V. Vicennati, L. Gagliardi, D. Colitta, S. Fiorini, G.E. Cognigni, M. Filicori, A.M. Morselli-Labate, Effect of long-term treatment of metformin added to hypocaloric diet on body composition, fat distribution, and androgen and insulin levels in abdominally obese women with and without the polycystic ovary syndrome. J. Clin. Endocrinol. Metab. 85(8), 2767–2774 (2000). CrossRefPubMedGoogle Scholar
  27. 27.
    M. Ozata, C. Oktenli, N. Bingol, I.C. Ozdemir, The effect of metforrnin and diet on plasma testosterone and leptin levels in obese men. Obes. Res. 9(11), 662–667 (2001). CrossRefPubMedGoogle Scholar
  28. 28.
    H. Rezvanian, M. Hashemipour, R. Kelishadi, N. Tavakoli, P. Poursafa, A randomized, triple masked, placebo-controlled clinical trial for controlling childhood obesity. World J. Pediatr. 6(4), 317–322 (2010). CrossRefPubMedGoogle Scholar
  29. 29.
    R.R. Wu, J.P. Zhao, X.F. Guo, Y.Q. He, M.S. Fang, W.B. Guo, J.D. Chen, L.H. Li, Metformin addition attenuates olanzapine-induced weight gain in drug-naive first-episode schizophrenia patients: a double-blind, placebo-controlled study. Am. J. Psychiatry 165(3), 352–358 (2008). CrossRefPubMedGoogle Scholar
  30. 30.
    S.S. Lim, R.J. Norman, P.M. Clifton, M. Noakes, The effect of comprehensive lifestyle intervention or metformin on obesity in young women. Nutr. Metab. Cardiovasc. Dis. 21(4), 261–268 (2011). CrossRefPubMedGoogle Scholar
  31. 31.
    E. Meaney, A. Vela, V. Samaniego, A. Meaney, J. Asbún, J.C. Zempoalteca, Z.N. Elisa, M.N. Emma, M. Guzman, J. Hicks, G. Ceballos, Metformin, arterial function, intima-media thickness and nitroxidation in metabolic syndrome: the mefisto study. Clin. Exp. Pharmacol. Physiol. 35(8), 895–903 (2008). CrossRefPubMedGoogle Scholar
  32. 32.
    M. Hasnain, W.V. Vieweg, S.K. Fredrickson, Metformin for atypical antipsychotic-induced weight gain and glucose metabolism dysregulation: review of the literature and clinical suggestions. CNS. Drugs 24(3), 193–206 (2010). CrossRefPubMedGoogle Scholar
  33. 33.
    C.H. Chen, M.C. Huang, C.F. Kao, S.K. Lin, P.H. Kuo, C.C. Chiu, M.L. Lu, Effects of adjunctive metformin on metabolic traits in nondiabetic clozapine-treated patients with schizophrenia and the effect of metformin discontinuation on body weight: a 24-week, randomized, double-blind, placebo-controlled study. J. Clin. Psychiatry 74(5), e424–e430 (2013). CrossRefPubMedGoogle Scholar
  34. 34.
    M.L. Evia-Viscarra, E.R. Rodea-Montero, E. Apolinar-Jiménez, N. Muñoz-Noriega, L.M. García-Morales, C. Leaños-pérez, M. Figueroa-Barrón, D. Sánchez-Fierros, J.G. Reyes-García, The effects of metformin on inflammatory mediators in obese adolescents with insulin resistance: controlled randomized clinical trial. J. Pediatr. Endocrinol. Metab. 25(1-2), 41–49 (2012). CrossRefPubMedGoogle Scholar
  35. 35.
    L.F. Jarskog, R.M. Hamer, D.J. Catellier, D.D. Stewart, L. Lavange, N. Ray, L.H. Golden, J.A. Lieberman, T.S. Stroup, METS Investigators, Metformin for weight loss and metabolic control in overweight outpatients with schizophrenia and schizoaffective disorder. Am. J. Psychiatry 170(9), 1032–1040 (2013). CrossRefPubMedGoogle Scholar
  36. 36.
    V. Nobili, M. Manco, P. Ciampalini, A. Alisi, R. Devito, E. Bugianesi, M. Marcellini, G. Marchesini, Metformin use in children with nonalcoholic fatty liver disease: an open-label, 24-month, observational pilot study. Clin. Ther. 30(6), 1168–1176 (2008). CrossRefPubMedGoogle Scholar
  37. 37.
    O. Snorgaard, L. Køber, J. Carlsen, The effect of metformin on blood pressure and metabolism in nondiabetic hypertensive patients. J. Intern. Med. 242(5), 407–412 (1997)CrossRefGoogle Scholar
  38. 38.
    L. Tock, A.R. Damaso, A. de Piano, J. Carnier, P.L. Sanches, H.M. Lederman, R.M. Ernandes, M.T. de Mello, S. Tufik, Long-term effects of metformin and lifestyle modification on nonalcoholic Fatty liver disease obese adolescents. J. Obes. 2010, 5722–5725 (2010). CrossRefGoogle Scholar
  39. 39.
    S. Wiegand, D. l’Allemand, H. Hübel, H. Krude, M. Bürmann, P. Martus, A. Grüters, R.W. Holl, Metformin and placebo therapy both improve weight management and fasting insulin in obese insulin-resistant adolescents: a prospective, placebo-controlled, randomized study. Eur. J. Endocrinol. 163(4), 585–592 (2010). CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Hong-Hong Ning
    • 1
  • Jiong Le
    • 2
  • Qian Wang
    • 1
  • Charlotte Aimee Young
    • 3
  • Bo Deng
    • 1
  • Peng-Xiang Gao
    • 1
  • Hai-Qiao Zhang
    • 1
  • Shu-Lan Qin
    • 1
    Email author
  1. 1.Department of Endocrinology, Third Affiliated HospitalNanchang UniversityNanchangChina
  2. 2.Jiangxi Aerospace Icloud Science and Technology Co., Ltd.NanchangChina
  3. 3.Department of OphthalmologyUniversity of CaliforniaSan FranciscoUSA

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