Iodine deficiency has long been overlooked as a public health problem, but people need to start taking this issue more seriously. Iodine is a necessary trace mineral which is essential for the formation of thyroid hormones, thyroxine and triiodothyronine. Symptoms of a deficiency include lethargy and tiredness, difficulty concentrating and unusual weight gain. In the diet, it is found mainly in seafood, kelp and dairy products.
During pregnancy, iodine deficiency (hypothyroidism) is a leading cause of intellectual disability in babies. But while most expectant mums know about the importance of making sure they take folic acid supplements, few realise the important of topping up their levels, usually in the form of a multivitamin. A recent study published in the British Journal of Nutrition found that only one third of women in Ireland knew about the importance of iodine in pregnancy and just 43 per cent knew what the nutrient was.
Studies show that young girls aged between 11 and 18 are most likely to have iodine deficiency. The National Diet and Nutrition Survey published in 2016 found that 26 per cent of girls had iodine intake below the Lower Reference Nutrient Intake (LRNI). We think this is because they don’t eat a lot of dairy in their diet, thinking it might be fattening. They also eat very little fish which does contain iodine. Around 16 per cent of boys of the same age have an iodine intake below the LRNI.
Girls and young women are more likely to have an unplanned pregnancy which may result in a live birth, so the problem of widespread iodine deficiency in this group is very worrying.
We need a public health campaign to underline the fact that supplementation could be as important as folic acid when it comes to women who are planning to have a baby and during the first trimester. School age children need to be given this information as well as older adults.
We need greater awareness of clinicians, midwives and health workers about the issue. They too may overlook its importance, focusing solely on folic acid instead.
Mandatory fortification with iodine in certain basic foods like flour or salt could be an option but more studies need to be done. In the meantime, a daily multivitamin will ensure that people are getting the minimum to greatly reduce the risk of avoidable damage to a growing foetus.