Is Folsäure useful for sleep?

Whether folate (folic acid) is useful for sleep lacks strong scientific support. Folate (vitamin B9) is involved in neurotransmitter synthesis (serotonin, dopamine) and homocysteine metabolism, which can influence sleep regulation. Low folate status has been linked to sleep disturbances in observational studies, especially in individuals with MTHFR variants. However, randomized controlled trials do not consistently show that folate supplementation improves sleep quality in healthy populations. The evidence is mixed, relying mostly on mechanistic reasoning and epidemiological associations. High-dose folic acid can also mask vitamin B12 deficiency, posing a safety risk. Therefore, while correcting a confirmed deficiency may be beneficial, routine supplementation for sleep is not evidence-based. A thorough medical assessment is recommended before use.