What to watch with MY FOODBOOK and fatigue?

When using MY FOODBOOK (a nutrigenetic test) to address fatigue, focus on key genetic markers that influence energy metabolism and detoxification. The GSTT2 gene (and related GSTT1, GSTM1) encodes glutathione S-transferase; null variants reduce detox capacity, potentially increasing oxidative stress and fatigue. Methylation genes (MTHFR, MTRR) affect homocysteine and B-vitamin status – imbalances can cause tiredness. Iron-related genes (HFE, TMPRSS6) and VDR (vitamin D receptor) are relevant because iron deficiency and low vitamin D are linked to fatigue. Caffeine metabolism (CYP1A2) and fat oxidation (PPARs, FTO) also influence energy. Evidence strength is mixed: many associations are from GWAS or mechanistic studies, not clinical trials. A genetic test alone cannot diagnose fatigue; lifestyle, sleep, stress, hormones (cortisol, thyroid), and gut microbiome play major roles. MY FOODBOOK offers personalized dietary suggestions, but do not replace medical evaluation. If fatigue persists, consult a doctor for comprehensive testing (e.g., iron, vitamin D, thyroid, cortisol).