The importance of good nutrition in the early development of children has been recognized for many decades. Nutritional experiences in early life can have profound and long-lasting effects on body weight in later life. For instance, malnutrition in early life as a result of poor nutrition during pregnancy and/or the lactation period may be stored on the offspring genome as epigenetic memory and persist into adulthood, thereby increasing the susceptibility to metabolic diseases such as obesity in later life. This area of epigenetics has become one of the fastest-growing and most complex areas of biological science.