was ist stoffwechsel — what are common causes?

Metabolism refers to all biochemical processes that convert nutrients into energy and building blocks. Common causes of metabolic issues include genetic variants (e.g., in FTO or PPARG), poor diet, lack of exercise, hormonal imbalances (thyroid, insulin), and aging. The provided context does not directly address these causes; it only notes that consumer DNA metabolism tests (e.g., MyBody-X) have limited predictive value and should be used as general guidance. Evidence is weak and practice-based. Always consult a healthcare professional for proper diagnosis.