What to watch with MTHFR and weight loss?

MTHFR variants (e.g., C677T) affect folate metabolism and can elevate homocysteine levels. However, a direct causal link to weight loss is not well established. Evidence (human-moderate) from association studies suggests that risk allele carriers may have slightly altered metabolic rates or fat oxidation, but effect sizes are small and overshadowed by lifestyle factors. The key practical takeaway: if you have an MTHFR variant, prioritize active methylfolate over synthetic folic acid, as conversion may be impaired. For weight loss, caloric balance, macronutrient composition, and physical activity remain paramount – genetics play a minor role. Consumer DNA tests can offer insights but should not dictate a weight loss plan. Be cautious of marketing that overstates MTHFR as a 'fat-burning gene.' Consult a healthcare professional for personalized advice, especially regarding supplementation and diet.