Is Folsäure useful for weight loss?

Folic acid (vitamin B9) is essential for cell division and DNA synthesis, but there is no strong evidence that it directly promotes weight loss. Some observational studies have found an inverse association between folate status and body weight, but these are confounded by diet quality and lifestyle. Randomized controlled trials have not shown a significant effect of folic acid supplementation on weight loss in overweight or obese individuals. The mechanistic rationale (e.g., via homocysteine metabolism or methylation) remains speculative and unsupported by clinical data. Therefore, folic acid should not be recommended as a weight loss aid. It is safe at standard doses but unnecessary for this purpose. A balanced diet rich in natural folate (leafy greens, legumes) is beneficial for overall health, but weight loss requires a sustained caloric deficit and lifestyle changes. Evidence grade: mixed/unclear (observational associations, lack of RCT support).