60% of Cork pregnant women have iodine deficiency, UCC study shows 

New research from University College Cork (UCC) has found that a significant portion of pregnant women in Ireland show signs of iodine deficiency.

The new study showed that 900 pregnant women (60% of those surveyed) had suboptimal iodine status, highlighting a need for increased nutritional awareness to support maternal and child health.

The study highlights the first large scale assessment of iodine status in pregnant women in Ireland. Published recently in the European Journal of Nutrition, the study evaluated iodine levels in more than 1,500 women who were pregnant with their first baby at Cork University Maternity Hospital.

The research was led by Dr Áine Hennessy from the Irish Centre for Maternal and Child Health Research (INFANT) at UCC and the Cork Centre for Vitamin D & Nutrition Research at the School of Food and Nutritional Sciences.

Other findings showed that the average urinary iodine concentration (UIC) was 125µg/L, below the World Health Organisation (WHO) recommended level of 150µg/L for pregnancy. It also found that women who were younger, had a higher BMI, lower education levels, or were not taking iodine containing supplements were more likely to be deficient, and that seasonal variation played a role with lower iodine levels during the summer months.

Dr Áine Hennessy, who is the lead researcher on the study, said that iodine is essential for thyroid hormone production, which supports a baby’s brain development during pregnancy.

“Our findings are particularly concerning as most women in the study were considered healthy and low risk and two thirds reported taking pregnancy supplements containing iodine. This suggests that additional public health measures may need to be addressed. Iodine deficiency is one of the most common micronutrient deficiencies worldwide, there is little public awareness of the important role that iodine plays in brain development during pregnancy. Women planning a pregnancy should ensure adequate iodine intake through their diet — including two or more servings of milk or yoghurt daily and eating white fish once a week is recommended by the HSE,” she added.

“For those following vegan or predominantly plant-based diets, it’s important to choose iodine fortified alternatives. We do not recommend kelp or seaweed supplements, as they can contain very high levels of iodine that can cause issues for the thyroid.”