A nutrigenetic approach to examine the relationship between vitamin B12 status and cardio-metabolic traits in multiple ethnic groups – findings from the GeNuIne Collaboration

Abstract

Low vitamin B12 concentration has been shown to be a risk factor for cardio-metabolic traits in numerous observational studies; however, the relationship has remained inconsistent. It is possible that certain genotypes jointly contribute to cardio-metabolic diseases and vitamin B12 deficiency, and these may be modulated by dietary factors. The main objective of this article is to summarise the findings from the GeNuIne (Gene-Nutrient Interactions) Collaboration on the effect of gene–nutrient interactions on vitamin B12 concentrations and cardio-metabolic disease risk factors in population-based studies from different ethnic groups. Interactions between vitamin B12-related single-nucleotide polymorphisms (SNPs) and protein energy intake (%) on waist circumference (Pinteration =0.002) and body fat percentage (Pinteraction =0.034) were observed in Sri Lankan and Indonesian populations, respectively. In the study in Brazilian adolescents, the metabolic and vitamin B12-related SNPs showed a significant interaction with dietary carbohydrate and protein intakes on oxidised low-density lipoprotein cholesterol and homocysteine concentrations, respectively. In the Asian Indian population, an association between obesity-related SNPs and vitamin B12 concentrations (p = 0.018) was observed. In summary, these studies in multiple ethnic groups show that the association between genetically low vitamin B12 concentrations and cardio-metabolic traits may be modified by dietary intake. Further studies utilising larger sample sizes are needed to confirm or refute our findings.