Why is iodine important for little ones

Iodine is one of those nutrients that doesn’t get very much attention, yet it’s important because it’s needed for a number of different functions in the body.

To begin with, iodine is essential for the thyroid gland to work properly. The thyroid gland produces hormones that help regulate many of our body’s systems, so inadequate iodine can have some serious knock-on effects.

In babies and young children, iodine is critical to development, especially brain development. Babies who don’t get enough iodine tend to have lower IQs and, in more severe cases, they may even have brain retardation and stunted growth. In fact, iodine deficiency is the single biggest cause of preventable brain damage in the world.

Thankfully, severe iodine deficiency is very uncommon in Australia. However, mild-to-moderate iodine deficiency is actually quite common, especially in New South Wales and Victoria.

Part of the reason for this is that the level of iodine in soils where we grow our food is low. We also don’t eat as much seafood as we should, and many people don’t have as much iodised table salt as they used to (which is generally a good thing for our health).

How much iodine do we need?

The National Health and Medical Research Council (NHMRC) recommends the following daily intakes of iodine:

  • Young babies aged 0–6 months – 90 μg
  • Older babies aged 7–12 months – 110 μg
  • Children aged 1–8 years – 90 μg
  • Pregnant women and women trying to get pregnant – 220 μg
  • Breastfeeding women – 270 μg

Pregnant and breastfeeding women need more, as they have their own iodine requirements to meet as well as those of their baby.

Where do we get iodine?

Babies who are breastfed rely on their mums’ breast milk for iodine, and that in turn depends on the mother’s diet. The main sources of iodine in Australia include fortified bread (but this does not include organic bread), dairy and seafood. As it is difficult for pregnant and breastfeeding women to get enough iodine to meet their needs from their diet alone, during this time a ‘top up’ is needed via a supplement. When choosing a breastfeeding multivitamin and mineral supplement, make sure it contains 150 μg iodine, which is the amount Australia’s NHMRC recommends for breastfeeding women. However, women with pre-existing thyroid conditions should seek advice from their medical practitioner before taking a supplement.

For babies who are formula fed, it is essential that the infant formula contains the right amount of iodine to fulfil their needs. Look for an infant formula that contains at least 12 μg iodine per 100 mL prepared formula, to be confident your little one is meeting the iodine intake levels recommended by Australia’s NHMRC.

If your baby is receiving both breast milk and infant formula, remember that your baby will be getting iodine from both milk supplies, so be sure to follow the NHMRC recommendations for iodine supplementation for as long as you are breastfeeding.

Once solids and other foods are introduced to your baby, the best sources of iodine include seafood (although take care to avoid fish known to be higher in mercury contamination, such as swordfish, orange roughy and ling) and seaweed. Canned fish is another good option, providing iodine with low levels of mercury. Oh, and why not swap your regular salt for iodised salt? This is another way to get extra iodine in the diet and you’ll not even notice the difference.

Eggs, dairy, vegetables and meat can also provide some iodine, but levels are highly dependent on the iodine content of the soil used to grow the food or feed the animal. These foods are therefore unreliable sources of iodine.

How can you ensure they are getting enough?

If you are pregnant or trying to get pregnant or breastfeeding, the NHMRC recommends a supplement of 150 μg a day. If you are already taking a multivitamin and mineral supplement, check the level of iodine in the product before taking any additional supplements. Most supplements today contain enough iodine. Be sure to talk to your Accredited Practising Dietitian if you are confused in any way, or feel free to contact our qualified dietitians.

For formula fed babies, check that the level of iodine in the formula is adequate to match the daily requirements listed above. As a guide, check that the formula you choose contains at least 12 μg iodine per 100 mL prepared formula. Oh, and remember that once your little one is eating solid foods from around six months, that he or she will receive iodine from their food, so look to include seafood and fortified bread in their daily food intake.

Toddlers and young children continue to require iodine, so ensure they eat seafood at least twice a week. It’s also good to include seaweed in their diets – sushi is a great way to do this – and use an iodised salt if you add any salt when cooking at home.

If you’re unsure whether you or your family are getting enough iodine, speak with your doctor or dietitian for further advice. Visit the Dietitians Association of Australia website to find a dietitian.

Article provided by:

Dr Joanna McMillan
Accredited Practising Dietitian