How much weight can you lose on metformin
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Weight Loss with Metformin: An Overview
Metformin and Weight Loss in Overweight and Obese Individuals
Efficacy of Metformin for Weight Reduction
Metformin, a medication primarily used to treat type 2 diabetes, has shown potential for weight loss in overweight and obese individuals. A systematic review and network meta-analysis involving 8461 participants across 34 trials found that metformin significantly decreased body mass index (BMI) and weight in various subgroups. Another meta-analysis of 21 trials with 1004 participants reported a modest reduction in BMI, with the most significant effects observed in individuals with a BMI greater than 35 kg/m².
Dosage and Duration of Metformin Treatment
The effectiveness of metformin for weight loss appears to be influenced by dosage and treatment duration. For adolescents, a dosage of 2000 mg/day was found to be more effective, while for adults, doses of 3000 mg/day for six months or 1000 mg/day for shorter periods were suitable. In a study involving 154 patients treated with up to 2500 mg/day of metformin over six months, the average weight loss was 5.8 kg, compared to a weight gain in the control group.
Metformin in Specific Populations
Elderly Individuals
In elderly populations, metformin treatment resulted in a small but significant weight reduction of approximately 2.23 kg over a period of at least 12 weeks. This weight loss was accompanied by improvements in cholesterol levels, suggesting additional cardiovascular benefits.
Women with Polycystic Ovary Syndrome (PCOS)
For women with PCOS, metformin alone resulted in modest weight loss. However, when combined with liraglutide, a glucagon-like peptide-1 receptor agonist, the weight loss was significantly greater, averaging 6.5 kg over 12 weeks.
Individuals with Schizophrenia or Schizoaffective Disorder
In a study of overweight outpatients with schizophrenia or schizoaffective disorder, metformin treatment over 16 weeks led to an average weight loss of 3 kg, along with improvements in BMI, triglyceride levels, and hemoglobin A1c levels.
Mechanisms of Weight Loss
The weight loss effects of metformin may be partly due to its impact on appetite and food intake. In a study of women with non-insulin-dependent diabetes mellitus (NIDDM), metformin reduced calorie intake and hunger ratings, leading to significant weight loss over 24 weeks. Additionally, metformin's insulin-sensitizing action may contribute to reductions in weight, centripetal obesity, and other metabolic risk factors.
Conclusion
Metformin has demonstrated efficacy in promoting weight loss across various populations, including adolescents, adults, the elderly, and individuals with specific conditions such as PCOS and schizophrenia. The extent of weight loss varies depending on dosage, treatment duration, and individual characteristics. While metformin is not officially approved as a weight loss drug, its potential benefits for weight reduction and metabolic health make it a valuable option for managing obesity and its related complications.
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