How to take metformin for weight loss
Pro Research Analysisby 
Searched over 200M research papers
Consensus Meter
How to Take Metformin for Weight Loss
Introduction to Metformin for Weight Loss
Metformin, a medication primarily used to treat type 2 diabetes, has been found to aid in weight loss for both diabetic and non-diabetic individuals. This article synthesizes research findings on the efficacy, dosage, and mechanisms of metformin for weight loss.
Efficacy of Metformin in Weight Loss
General Efficacy in Overweight and Obese Individuals
Research indicates that metformin significantly decreases body mass index (BMI) and body weight in overweight and obese individuals. A systematic review and network meta-analysis involving 8461 participants found that metformin effectively reduced BMI and weight across various subgroups. Another study confirmed that metformin led to a mean maximum weight loss of 8 kg over 24 weeks in obese women with non-insulin-dependent diabetes mellitus (NIDDM).
Efficacy in Children and Adults
Metformin has shown varying degrees of efficacy in children and adults. In children, more than half of the studies reported a greater reduction in BMI with metformin compared to controls after six months. In adults, metformin consistently resulted in small but significant weight reductions, with 11 out of 14 studies showing greater weight loss compared to placebo.
Dosage and Intervention Period
Optimal Dosage for Adolescents and Adults
The optimal dosage and intervention period for metformin vary by age group. For adolescents, a dosage of 2000 mg/day ranked higher in efficacy, while 1000 mg/day for three months was deemed most suitable. For adults, dosages of 3000 mg/day for six months and 1000 mg/day for 0.5 months were found to be effective.
Short-Term and Long-Term Use
Short-term studies have shown that metformin can lead to significant weight loss within a few months. For instance, a 16-week trial found that metformin led to a weight loss of 2.96 kg in overweight or obese patients with type 2 diabetes. Long-term studies, such as the Diabetes Prevention Program Outcomes Study, demonstrated that weight loss with metformin is durable for at least 10 years, provided there is adherence to the medication.
Mechanisms of Action
Appetite Suppression and Caloric Intake
Metformin's weight loss effects are partly due to its ability to suppress appetite and reduce caloric intake. A study found that metformin reduced calorie intake and hunger ratings in a dose-dependent manner, with the 1700 mg dose having the most pronounced effect. Another study suggested that metformin increases the secretion of growth differentiating factor 15 (GDF15), which suppresses appetite and promotes weight loss.
Gut Microbiota Alteration
Metformin also induces changes in gut microbiota, which may contribute to its weight loss effects. A clinical trial found that metformin led to a significant increase in the abundance of Escherichia/Shigella in the gut microbiota of non-diabetic obese women, although the overall composition remained largely unchanged.
Safety and Tolerability
Common Side Effects
Metformin is generally safe and well-tolerated, but gastrointestinal symptoms such as nausea and diarrhea are common, especially at higher doses. These symptoms tend to decline over time. A meta-analysis of elderly patients found that metformin led to a small reduction in body weight and slight improvements in blood lipid profiles, suggesting it is a safe option for older adults.
Adherence and Long-Term Safety
The long-term safety of metformin has been well-documented. The Diabetes Prevention Program Outcomes Study reported no significant safety issues over a 10-year period, and weight loss was closely related to adherence to the medication.
Conclusion
Metformin is an effective and safe option for weight loss in both diabetic and non-diabetic individuals. Optimal dosages and intervention periods vary by age group, and the medication works through mechanisms such as appetite suppression and gut microbiota alteration. Long-term adherence to metformin is crucial for sustained weight loss.
Sources and full results
Most relevant research papers on this topic