The quality of the food that you eat before - and during - pregnancy may reduce the chances of your baby having certain birth defects such as neural tube defects according to a 2011 study from Stanford University: The National Birth Defects Prevention Study. Birth defects which were found to be connected to the quality of a mother's diet included: cleft lip, cleft palate and neural tube defects which can cause anencephaly (where the baby is born without a brain) or spina bifida (where the spine does not close properly exposing the spinal cord).

This study was huge and included over 3000 cases of children born with birth defects and over 6,000 normally formed controls in the USA. Mothers were questioned about their dietary intakes and scored using two well respected assessment instruments to evaluate the 'Mediterranean Diet Score' (MDS) and their 'Diet Quality Index' (DQI). Together these scoring systems award high scores for diets rich in fruits and vegetables, whole grains and healthy fats suh as olive oil, fish and seafood and award low scores for processed foods, saturated fats and red meats. The researchers concluded that:

"...increasing diet quality based on either index was associated with reduced risks for the birth defects studied. The strongest association was between anencephaly and DQI (Dietary Quality Index)."

"Healthier maternal dietary patterns, as measured by diet quality scores, were associated with reduced risks of NTDs and clefts."

"These results suggest that dietary approaches could lead to further reduction in risks of major birth defects and complement existing efforts to fortify foods and encourage periconceptional multivitamin use."

The routine recommendation that women take folic acid in prenatal vitamins - since 1991 - and measures to fortify foods with folic acid - since 1998 - have helped to reduce the incidence of neural tube defects but have by no means eradicated the condition. Studies have shown that other individual nutrients may help to prevent neural tube defects too but studies on the quality and nutrient density of a woman's diet have been lacking.

This study didn't just measure the effectiveness of a single nutrient - such as folic acid - but instead looked at the quality and nutrient density of women's diets highlighting the fact that food can be enormously protective. Lead researcher Suzan Carmichael, PhD stated that:

"Our study showed for the first time that the overall quality of the diet, and not just a single nutrient, matters in terms of reducing the risk of birth defects..."

Diet proved to be very protective; women with the highest nutritional scores (top quartile) were 36 to 51 percent less likely than women with lowest quality diets (lowest quartile) to have a baby with anencephaly, and 24 to 34 percent less likely to have a baby with cleft lip.

A varied whole food diet rich in fruits, vegetables, whole grains, beans, healthy fats, hormone-free meats and dairy foods, mercury-free fish and other healthy foods, typical of a Mediterranean diet may offer significant protection against birth defects. Following a healthy pre-conception and pregnancy diet is just as important as taking a good quality pre-natal vitamin.

This article is purely for educational and informational purposes and is not intended to substitute for medical diagnosis or treatment or nutritional advice for which you should consult a physician or licensed dietitian.


Suzan L. Carmichael; Wei Yang; Marcia Lynn Feldkamp; Ronald G. Munger; Anna Maria Siega-Riz; Lorenzo D. Botto; Gary Shaw; for the National Birth Defects Prevention Study. Reduced Risks of Neural Tube Defects and Orofacial Clefts With Higher Diet Quality. Archives of Pediatrics & Adolescent Medicine, 2011; DOI: 10.1001/archpediatrics.2011.185