Genotype-based personalised nutrition for obesity prevention and treatment: are we there yet?

Interactions between genotype and dietary intake include genetic moderation of the effect of dietary intake on disease development (nutrigenetics). Research on nutrigenetics has focused mainly on single-nucleotide polymorphisms (SNPs) and supports the notion that interactions between genes, diet, other lifestyle factors, disease, and time (life cycle span), contribute to the risk of most polygenic nutritionrelated diseases. Typically, genotype-based personalised nutrition involves genotyping for a number of susceptibility SNPs associated with the prevention, or management, of a particular disease. Dietary advice is then personalised to the individual’s genotype to ensure optimal prevention or treatment outcomes. To ensure evidence-based practice, research design and methodology, applied in the investigation of relevant associations, and confirmation of causality, should be appropriate and rigorous. The process of identifying SNPs associated with disease patterns is ongoing. Of note is that the combined effect on body mass index of the SNPs at the currently confirmed 32 loci is a modest 1.45%, bearing in mind that the estimated heritability of obesity is 40-70%. Conclusions formulated by various researchers on the translation of nutrigenetics research into personalised nutrition, including obesity prevention and management, indicate that scientists hold the opinion that more research is necessary before evidence-based practice in this area can be guaranteed.