Drinking milk during pregnancy may be essential to not only your children's physical health, but also their fetal brain development. Researchers from UK have produced findings that suggest mothers who don't get the recommended amount of iodine give birth to children with lower IQ scores.

"Pregnant women and those planning a pregnancy should ensure adequate iodine intake; good dietary sources are milk, dairy products and fish," said Dr. Sarah Bath, Ph.D., who co-authored the study.

"Women who avoid these foods and are seeking alternative iodine sources can consult the iodine fact sheet that we have developed, which is available on the websites of the University of Surrey and the British Dietetic Association. Kelp supplements should be avoided as they may have excessive levels of iodine."

Iodine is a dietary supplement found in milk and other dairy products necessary for thyroid hormone regulation. Thyroid hormones in turn control the production of proteins and enzymes that support the skeletal and central nervous system development of the fetus.

The study, led by Margaret Rayman, a professor of nutritional medicine from the University of Surrey, was based on data from the Avon Longitudinal Study of Parents and Children (ALSPAC). The cohort analysis launched back in the early 1990s tracked the pregnancies of more than 14,000 women in their first trimester.

To narrow their results, Rayman and her colleagues examined 1,040 pregnant women who were considered iodine deficient. The children of this study were tested at eight years old for IQ levels, and then again for reading abilities at nine. Test scores were considerably lower in children of mothers who didn't get the appropriate amount of dietary iodine.

"Our results clearly show the importance of adequate iodine status during early pregnancy, and emphasise the risk that iodine deficiency can pose to the developing infant, even in a country classified as only mildly iodine deficient," Rayman concluded.

A similar study conducted back in July 2004 analyzed different food products that contained adequate dietary iodine and inadequate dietary iodine. Although the researchers established that iodine deficiency is the leading cause of preventable mental retardation, the findings also showed that inadequate dietary iodine intake can lead to a bevy of pregnancy health concerns including decreased fertility, stillbirth, and lack of neurological development.

The results of this study were published in the online edition of The Lancet.

Source: Bath SC, Steer CD, Golding J, Emmett P, Rayman MP. Effect of inadequate iodine status in UK pregnant women on cognitive outcomes in their children: results from the Avon Longitudinal Study of Parents and Children (ALSPAC). The Lancet. 2013.