Can Folsäure help with sleep?

Whether folic acid (vitamin B9) can improve sleep is not clearly supported by scientific evidence. Folic acid is crucial for DNA synthesis and homocysteine metabolism, and deficiency can cause fatigue and neurological symptoms. Some observational studies suggest a link between low folate levels and sleep disturbances, but randomized controlled trials demonstrating a direct sleep-enhancing effect are lacking. The evidence is therefore 'unclear'. Additionally, folic acid (the synthetic form) differs from natural dietary folate. Supplementation without confirmed deficiency is not recommended, as high doses can mask vitamin B12 deficiency, especially in older adults. For sleep issues, established factors like sleep hygiene, stress, and underlying medical conditions should be addressed first. Genetic testing for MTHFR variants (e.g., rs1801133) may influence folate needs, but the direct impact on sleep remains unproven. Conclusion: folic acid is not a sleep aid; if deficiency is suspected, consult a doctor.