This Generic Drug Helps Weight Loss: Now We May Know Why

Metformin, a commonly prescribed drug primarily used to treat type-2 diabetes, is known to cause weight loss in some people. This effect is beneficial for diabetic patients who experience it, but the actual mechanism behind the weight loss hasn't been clear. That may have changed with a newly published study that details the reason why metformin may trigger weight loss.

In addition to helping treat type-2 diabetes in patients suffering from it, metformin has shown promise for preventing this disease in people who are at high risk for developing it. Beyond that, past studies have also found evidence that metformin may help cause weight loss in people who don't have type-2 diabetes, making it a potential anti-obesity drug.

A study recently published in the prestigious journal Nature details the potential cause of this weight loss and it involves a protein called GDF15. This protein is associated with lower food consumption and lower body weight — and, it turns out, circulating levels of this same protein were found to increase when taking metformin.

The increased levels were identified in two different randomized controlled clinical trials, according to the study. Positive effects related to metformin and obesity were observed in wild-type mice; for example, wild-type mice fed metformin experienced an increase in their circulating GDF15 levels.

As well, this drug was found to prevent weight gain in mice fed a high-fat diet, but not in mice that lacked GDF15 or its GFRAL receptor. As well, blocking this receptor is said to have reversed the effects of metformin on lowering body weight in obese mice fed a high-fat diet. The study concludes that metformin's effect on GDF15 is 'necessary for its beneficial effects on energy balance and body weight,' among other things.