What do studies say about MTHFR Training?

The concept of 'MTHFR training' originates from direct-to-consumer genetic testing, claiming that variants in the MTHFR gene (e.g., C677T) influence athletic performance, recovery, or injury risk. However, the scientific evidence is weak. MTHFR encodes an enzyme involved in folate metabolism; certain variants may modestly affect methylation, but their impact on exercise-related outcomes is small, inconsistent, or only mechanistic. No robust studies support using MTHFR genotype to guide training programs. Most claims rely on underpowered association studies or overinterpreted data. Furthermore, nutritional factors (folate, vitamin B12) and general training principles are far more influential. 'MTHFR training' is not evidence-based and should not be considered a medical or performance recommendation. Be cautious of marketing that oversimplifies complex training adaptations into a single genetic test.