How are Homocystein and Müdigkeit related?

Homocysteine is a sulfur-containing amino acid produced during methionine metabolism. Elevated homocysteine (hyperhomocysteinemia) is linked to oxidative stress, endothelial dysfunction, and impaired methylation – processes that may indirectly contribute to fatigue. Some studies report higher homocysteine levels in people with chronic fatigue syndrome (ME/CFS) or fibromyalgia. However, the evidence for a direct causal relationship is modest: fatigue is multifactorial, and homocysteine is just one potential contributor. Deficiencies in vitamin B12, B6, or folate – which help lower homocysteine – can also cause fatigue. Supplementing these vitamins reduces homocysteine but does not reliably relieve fatigue unless a deficiency exists. Consumer tests for homocysteine (blood) or genetic variants (e.g., MTHFR) offer clues but not diagnoses. Clinical relevance remains debated. Evidence grade: human-moderate. Caveat: Interpretation requires medical context and B-vitamin status assessment.