Myths vs facts: Fertility Check | Fruchtbarkeits-Test and Müdigkeit

Myths vs. Facts: Fertility Check and Fatigue. Many direct-to-consumer (DTC) DNA tests claim that single gene variants (e.g., MTHFR, FTO, HTR2A) can predict fertility issues or chronic fatigue. The scientific evidence for such claims is weak or purely mechanistic. For example, the MTHFR C677T polymorphism is often linked to fertility problems, but large meta-analyses find no clinically meaningful effect. Similarly, linking FTO variants to fatigue is not supported by robust studies. The reality: fertility and fatigue are multifactorial – hormones, sleep, diet, stress, environment, and lifestyle have far greater impact than individual SNPs. A DNA test can at best provide weak clues, but not a diagnosis or personalized therapy. Anyone experiencing persistent fatigue or planning fertility treatment should seek medical evaluation (blood count, thyroid, iron status, etc.) rather than relying on supplement recommendations from a genetic test. The evidence level is 'mechanistic/unclear'. Safety note: self-supplementing with high-dose 5-MTHF or melatonin can cause adverse effects.