According to the Centers for Disease Control (CDC) 12 percent of children aged 2 to 19 years are obese—triple the number it was in 1980. This increase is attributed, in part, to the Standard American Diet (SAD), a poor diet high in refined carbohydrates, bad fats, and sugar, and low in high-fiber foods like whole grains and fruits and vegetables.
A recent study takes a look at fat intake of pregnant women and fat accumulation in their children by age 3. Specifically, the study looked at the status of two types of polyunsaturated fatty acids (PUFAs)—omega-6 and omega-3. These fats are both essential to the diet. The Standard American Diet is very high in the omega-6 fatty acids, found in vegetable oils and grains like corn. Omega-3 fatty acids, however, are not consumed in adequate amounts, creating an imbalance in the ratio of omega-6 to omega-3s.
Omega-3 fatty acids, especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) found primarily in fish, promote optimal development of the fetal brain and immune system. Many women in the U.S. do not consume enough of these beneficial omega-3s. In a study published in the American Journal of Clinical Nutrition, researchers assessed mid-pregnancy intake of omega-3 and omega-6 fatty acids and tested plasma fatty acid levels of the mother and umbilical cord fatty acid levels of the infant to determine omega-3 status. At age 3, body mass index (BMI) and skin fold measurement were taken to determine obesity in the children.
The odds of obesity in 3-year-olds were two to four times higher when cord blood had a high ratio of omega-6 to omega-3 fatty acids. When maternal intake of omega-3s was higher, or when the omega 3/6 ratio was closer to recommended levels, the odds of childhood obesity were lower.
It has long been known that omega-3s, especially DHA, are necessary for brain development of the fetus and infants. The study also found that only three percent of mothers consumed the recommended 200 mg of DHA per day in the last month of pregnancy, when DHA is most rapidly transferred from the mother to fetus. This study is building the evidence that omega-3 fatty acids provide a variety of benefits for infants and children that go beyond brain and eye development.