In this land of plenty, it's hard to believe that our diet could be deficient in any nutrient to the point where supplementation would be necessary. But the American diet tends to lack appropriate amounts of some nutrients, whether it's because we don't consume adequate amounts of certain foods, we've lost our taste for certain foods or some things are not widely available. While the diet of most Americans does contain adequate amounts of fat, our daily consumption of an essential fatty acid known as docosahexaenoic acid (DHA) is less than half of the recommended level. This omega-3 fatty acid is contained in high quantities in the brain, retina and nervous system, and it's critical to the development of a fetus and growing child.
Because a fetus demands DHA, and because we don't consume enough of it, pregnancy is associated with a decline in DHA levels. In addition, health advisories limit the intake of fish in pregnancy — and fish is one of the richest sources of this nutrient.
What is DHA?
Certain fatty acids are indispensable for human development and health and must be consumed in our diet. These are collectively known as essential polyunsaturated fatty acids. While consumption of trans fatty acids has been discouraged, research has confirmed the many benefits of eating foods high in polyunsaturated fatty acids.
DHA is one of the fatty acids critical for the development of a fetus. An appropriate intake of DHA, both prior to and during the pregnancy and the postpartum period, is essential for normal placental, fetal, neonatal and early childhood growth. It's an important element in the development of cell membranes and in the formation of new tissues. The brain and nerves of the human body are particularly rich in DHA, and the cerebral accumulation of these fatty acids may have been decisive in our evolution. The fetal brain has a growth spurt in the third trimester of pregnancy and during early childhood, so the intake of essential fatty acids is especially important during late pregnancy and the early years of life. DHA accumulates in the fetal brain three to five times more rapidly during the last three months of pregnancy than it does during the first months of gestation.