MY FOODBOOK: what are common causes?

Common causes of food-related issues (intolerances, sensitivities, or metabolic responses) are multifactorial. They include genetic variants affecting digestion, gut microbiome composition, enzyme deficiencies (e.g., lactase), and environmental factors. DNA tests like MyBody-X may identify variants such as rs1260326 (linked to glucose metabolism) or rs601338 (FUT2 non-secretor, associated with lower Bifidobacterium levels). However, the evidence is mixed: some associations come from GWAS or mechanistic studies, while others are preliminary or not clinically validated. Microbiome testing can reveal low diversity, which may correlate with bloating or fatigue, but these are observational findings. Importantly, genetic and microbiome tests are not diagnostic tools. Persistent symptoms should be evaluated by a healthcare professional. The root causes are often a combination of genetics, diet, lifestyle, and gut health – no single test provides a complete answer.