Genetic Variants Shaping Inter-individual Differences in Response to Dietary Intakes—A Narrative Review of the Case of Vitamins

Abstract

Recent advances in the field of nutrigenetics have provided evidence on how genetic variations can impact the individuals' response to dietary intakes. An objective and reliable assessment of dietary exposures should rely on combinations of methodologies including frequency questionnaires, short-term recalls or records, together with biological samples to evaluate markers of intake or status and to identify genetic susceptibilities. In an attempt to present current knowledge on how genetic fingerprints contribute to an individual's nutritional status, we present a review of current literature describing associations between genetic variants and levels of well-established biomarkers of vitamin status in free-living and generally healthy individuals. Based on the outcomes of candidate gene, genome-wide-association studies and meta-analyses thereof, we have identified several single nucleotide polymorphisms (SNPs) involved in the vitamins' metabolic pathways. Polymorphisms in genes encoding proteins involved in vitamin metabolism and transport are reported to have an impact on vitamin D status; while genetic variants of vitamin D receptor were most frequently associated with health outcomes. Genetic variations that can influence vitamin E status include SNPs involved in its uptake and transport, such as in SCAR-B1 gene, and in lipoprotein metabolism. Variants of the genes encoding the sodium-dependent vitamin C transport proteins are greatly associated with the body's status on vitamin C. Regarding the vitamins of the B-complex, special reference is made to the widely studied variant in the MTHFR gene. Methodological attributes of genetic studies that may limit the comparability and interpretability of the findings are also discussed. Our understanding of how genes affect our responses to nutritional triggers will enhance our capacity to evaluate dietary exposure and design personalized nutrition programs to sustain health and prevent disease.

Personalized Nutrition Intervention Improves Health Status in Overweight/Obese Chinese Adults: A Randomized Controlled Trial

“…Vitamin B2, for example, is a vital cofactor within the electron transport chain, Krebs cycle, and beta-oxidation (fat burning) ( 45 ), which explained why the increased vitamin B2 intake is a major contributor of BMI reduction. Vitamin B6 and vitamin B12 are involved in one-carbon metabolism, in which MTHFR plays a critical role ( 46 ). Although there is a lack of clear evidence of how promoted one-carbon metabolism is related to weight loss, it is reported that vitamin B intake is positively associated with fat-free mass in overweight/obese females ( 47 ), and according to a meta-analysis with 9,075 participants, higher serum vitamin B12 levels are inversely associated with obesity ( 48 ).…”

Genetic Variants in Folate and Cobalamin Metabolism-Related Genes in Pregnant Women of a Homogeneous Spanish Population: The Need for Revisiting the Current Vitamin Supplementation Strategies

“…Preeclampsia is characterised by hypertension accompanied by proteinuria in pregnant women over 20 weeks of gestation. This disease can affect both the foetus and the mother and, in extreme situations, can compromise the life of both [47][48][49]. A meta-analysis report by Wang et al (2013) [50] showed a significant association between the MTHFR T allele and pre-eclampsia among Caucasians and people of Asian descent but not among people of African descent.…”

Genetic polymorphisms related to the vitamin D pathway in patients with cirrhosis with or without hepatocellular carcinoma (HCC)

“…Incidentally, this study showed a higher frequency of reduced vitamin D levels in patients with cirrhosis with or without HCC carrying at least one mutant allele (_/A) for DBP-rs4588 , compared to the control group, in agreement with Santos et al [ 37 ]. There is also a reference to the influence of the polymorphisms of DBP-rs7041 and DBP -rs4588 affecting the binding affinity of DBP with vitamin D, which could consequently influence its anti-tumorigenesis activity [ 41 ]. However, haplotype variations in different ethnicities may contribute to divergences between studies [ 39 , 42 ].…”