Epigenetics is the study of genetic variations that are caused within an individual, by external or environmental factors that can switch genes on and off, as opposed to changes in DNA sequence which happen as genes are passed down to the next generation. One of the most potent ways epigenetics can change is through nutrition.  In fact, one of the main reasons good nutrition is so important is because healthy food choices will minimize the expression of disease-causing genes we may have inherited. Unlike behavior or stress, diet is one of the more easily studied, and therefore better understood, environmental factors in epigenetic change. The nutrients we extract from food enter metabolic pathways where they are broken down, modified, and assembled into molecules the body can use. One such pathway is responsible for making methyl groups (CH3), which interact with important epigenetic tags that silence genes. Familiar nutrients like folic acid, B vitamins, and SAM-e (S-Adenosyl methionine, a popular over-the-counter supplement) are key components of this methyl-making pathway. Diets high in these methyl-donating nutrients can rapidly alter gene expression, especially...