What to watch with DNA Stoffwechseltest and Müdigkeit?

A DNA metabolism test (e.g., from MyBody-X) examines genes involved in nutrient processing, methylation, and detoxification – such as MTHFR, FUT2, or VDR. These can theoretically relate to fatigue if, for example, folate or B12 activation is impaired. However, the evidence is mixed: most SNPs have small effect sizes, and fatigue is multifactorial (sleep, stress, iron deficiency, thyroid, etc.). The test does not provide a diagnosis, only clues. Blood biomarkers (ferritin, vitamin B12, vitamin D, TSH) and a clinical workup are more reliable. Caution against self-supplementation: high-dose folic acid can mask B12 deficiency in MTHFR variants. The test can be a useful starting point but should not replace medical evaluation.