Lifestyle Interventions for Weight Control Modified by Genetic Variation: A Review of the Evidence

Excess weight gain is a result of the interaction between diet, environment, and genes. Evidence suggests that responses to lifestyle interventions to manage weight are partially modified by genetic factors. This review is aimed at summarizing the current evidence from studies done on gene variants - single nucleotide polymorphisms (SNPs) - and intervention outcomes on weight loss and obesity-related traits.

Intervention studies published in English between 2000 and August 2018 were retrieved from PubMed, Google Scholar, and Web of Science using various keywords.

This article is a review of 36 studies conducted in 13 different countries which included a total of 15,931 participants between 19 and 70 years of age. The effect of 26 genes and 64 SNPs on the reduction of body weight and metabolic risk factors in response to diet, exercise, and lifestyle interventions was reviewed.

Gene-lifestyle interaction studies on the same candidate gene in different populations have reported information which is challenging to interpret. Thus, it is difficult to arrive at a particular model for a strategy on weight management at this point in time. Most of the intervention studies focus on the effect of variants of a single candidate gene on weight loss. Further evidence from large-scale studies is necessary to assess the effect of multiple candidate genes to compute a gene score that could be used in a model intervention programme. Our review suggests that a healthy lifestyle with a balanced diet and regular physical activity will benefit individuals who carry the risk alleles of the obesity-related candidate genes. This message should be the mainstay of the recommendations and guidelines published by nutrition societies across the world.