Role of diet in epigenetics: a review

Abstract

Epigenetics refers to the mechanisms that alter gene expression without altering the primary DNA sequence. The epigenetic modifications may be due to cytosine base methylation in DNA or by post-translational biochemical modifications of histones, the core proteins of nucleosomes. Epigenetic mechanisms are heritable and reversible. Epigenetic modifications can occur in response to environmental stimuli, of which the most important one is diet. Nutrients can modify physiologic processes through epigenetic mechanisms. The dietary nutrients enter metabolic pathways and get modified in to simpler forms for the body to utilize. One carbon cycle is such a unique pathway which produces methyl groups to silence the genes. Nutrients like methionine, Vitamin B12, folic acid, and Vitamin B6, are the key components of this pathway. These methyl-donating nutrients in the diet can alter gene expression. The knowledge regarding nutritional epigenetics is still limited. As Epigenetics is reversible in nature, it is now considered as an attractive field of nutritional intervention. In the future, we need to investigate on more nutrients or bioactive food compounds to find the ones that can improve human health.