Nutrition During Pregnancy and the Effect of Carbohydrates on the Offspring’s Metabolic Profile: In Search of the “Perfect Maternal Diet”

Fetal growth and development is primarily dependent upon the nutritional, hormonal and metabolic environment provided by the mother. A wartime famine study in Holland first showed that a low food intake reduces the glucose offered to the fetus and thus produces smaller size infants at birth. Maternal glucose regulation is however affected by numerous factors including physiological changes of pregnancy (e.g. insulin resistance [IR]), pathological conditions (e.g. gestational diabetes mellitus) and maternal nutrition. Maternal glucose is substantially influenced by the type of carbohydrates in the diet through its direct effect on glycemia. The rate at which each carbohydrate raises blood glucose levels after ingestion, can be measured via the dietary glycemic index (GI). Carbohydrate type and the GI of the diet enhance or inhibit abnormal hyperglycemia during pregnancy caused by either pathological conditions or the inability of the mother to cope with the physiological IR of pregnancy. In turn, maternal gestational hyperglycemia may be involved in the pathogenesis of IR, impaired glucose tolerance, type 2 diabetes mellitus, the Metabolic Syndrome and subsequent cardiovascular diseases in adult offspring. A low GI maternal diet has been associated with measurable benefits to the offspring. These include a positive effect on altering maternal blood glucose production, insulinemia and reduced adiposity as well as fetal and placental insulin and glucose regulation, fetal growth, birth weight and offspring adiposity. We review the possible links between dietary carbohydrate in health during pregnancy and the effect of maternal carbohydrate ingestion on programming the offspring's metabolic profile.