Can Folsäure help with blood sugar?

Folic acid (vitamin B9) is primarily involved in cell division, DNA synthesis, and homocysteine metabolism. Some observational studies suggest a link between low folate status and increased insulin resistance, but evidence for a direct blood-sugar-lowering effect of folic acid supplementation is weak. Randomized controlled trials have not consistently shown improvements in fasting glucose or HbA1c in healthy individuals or those with diabetes. High doses may even pose risks (e.g., masking vitamin B12 deficiency). Adequate folate intake through diet (leafy greens, legumes) is beneficial, but targeted supplementation for blood sugar control is not supported by strong evidence. Caveat: Folic acid is indicated during pregnancy for neural tube defect prevention, not for glucose regulation. Evidence grade: mechanistic/unclear.