Maternal nutrition: effects on health in the next generation.

Nearly 20 years ago, it was discovered that low birthweight was associated with an increased risk of adult diabetes and cardiovascular disease (CVD). This led to the hypothesis that exposure to undernutrition in early life increases an individual's vulnerability to these disorders, by 'programming' permanent metabolic changes. Implicit in the programming hypothesis is that improving the nutrition of girls and women could prevent common chronic diseases in future generations. Research in India has shown that low birthweight children have increased CVD risk factors, and a unique birth cohort in Delhi has shown that low infant weight, and rapid childhood weight gain, increase the risk of type 2 diabetes. Progress has been made in understanding the role of specific nutrients in the maternal diet. In the Pune Maternal Nutrition Study, low maternal vitamin B12 status predicted increased adiposity and insulin resistance in the children, especially if the mother was folate replete. It is not only maternal undernutrition that causes problems; gestational diabetes, a form of foetal overnutrition (glucose excess), is associated with increased adiposity and insulin resistance in the children, highlighting the adverse effects of the 'double burden' of malnutrition in developing countries, where undernutrition and overnutrition co-exist. Recent intervention studies in several developing countries have shown that CVD risk factors in the offspring can be improved by supplementing undernourished mothers during pregnancy. Results differ according to the population, the intervention and the post-natal environment. Ongoing studies in India and elsewhere seek to understand the long-term effects of nutrition in early life, and how best to translate this knowledge into policies to improve health in future generations.