“Effect of Two Weekly Servings of Cod for 16 Weeks in Pregnancy on Maternal Iodine Status and Infant Neurodevelopment: Mommy’s Food, a Randomized-Controlled Trial.” This study was conducted to examine how increasing cod intake in pregnant women would impact their iodine status and the cognitive development of their infants at 11 months old. Women of childbearing age are most vulnerable to iodine deficiency, especially in countries without iodized salt. The women who participated in this study had mild to moderate iodine deficiencies. They were either assigned to the intervention group of women who would consume cod, or the control group of women who would stick to their regular diets. The intervention group was told to consume 200 grams of cod two times per week for weeks 20-36 of their pregnancy. Cod was chosen so that the effect of a non-fortified iodine-rich food source could be investigated. Urinary iodine concentration (UIC) was measured to examine maternal iodine status. The neurodevelopment of the infants was measured using the Bayley Scales of Infant and Toddler Development third edition, or Bayley-III. This assessment tool consists of cognitive, language, and motor scales.
The RDA for iodine is 150 mcg/day for non-pregnant women and 220 mcg/day for pregnant women. The results of the study found that UIC greatly increased in the intervention group after cod consumption compared to the control group. However, UIC didn’t even meet the RDA of 150 mcg for nonpregnant women. For the infants, the intervention group actually scored lower on the cognitive scale than the control group while language and motor scores were similar for both groups. This could be because the first trimester is vital for fetal brain development and the cod was introduced much later into the pregnancies.
Some main talking points I would provide to my client about this study are:
Maternal iodine status can be somewhat improved during pregnancy with non-fortified food sources, but this improvement may not be enough to prevent iodine deficiency
Increasing intake of iodine too far into pregnancy can negatively impact cognitive development of infants
More research is needed to support iodine supplementation during pregnancy
This study speaks to the importance of treating deficiencies and taking prenatal vitamins before conception, not just after conception
The main take-home message I would give my client is that the relationship between a mother’s nutrition and her infant’s growth and development is more complex and critical than most people realize. The food that a mother consumes before and during pregnancy, and during lactation is essential to the fetus and the infant as they rely solely on their mother for nutrients. These nutrients directly affect brain development and bodily functions. When and what nutrients are consumed, and the quality of those nutrients are equally important for pregnancy and infancy.
