Can Folsäure help with fatigue?

Folic acid (vitamin B9) can help with fatigue if a deficiency is confirmed. Deficiency leads to megaloblastic anemia, whose hallmark is fatigue and weakness. In the general non-deficient population, evidence for an energy-boosting effect is weak. Trials show no significant improvement in fatigue or vitality with folic acid supplementation in people with normal levels. Additionally, high folic acid intake can mask vitamin B12 deficiency, a risk especially for older adults and vegans. Before taking folic acid for fatigue, a blood test (e.g., MyBody-X nutrient deficiency test) should confirm a true deficiency. Fatigue has many causes—sleep deprivation, stress, thyroid issues—and folic acid is not a universal energy remedy.