Pregnancy nutrients: iodine
Brain Builder
The importance of iodine
Iodine is a key nutrient for pregnancy. As well as being involved in many functions and processes of the body, it is vital for your baby’s brain development. Learn what this trace element does and how to include it in your pregnancy diet.
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Iodine helps to support: Normal cognitive development |
Iodine: A vital nutrient for good health
Iodine is a trace element found in dairy foods, fish and some other foods1. One of the less well-known nutrients, it has a vital role to play in your everyday health and your baby’s incredible journey from conception to birth.
Iodine is needed to make thyroid hormones. These hormones affect the way your cells function, affecting the processes of your body, including heart rate and metabolism.
During pregnancy, your baby’s cells also rely on your iodine intake, including the cells in their rapidly developing brain2.
Why you need more iodine during pregnancy
Iodine is important during pregnancy for three reasons2:
- You need thyroid hormones for your own body processes
- Your body provides your baby with iodine
- It is thought that you might naturally lose more iodine than usual during pregnancy
Building a healthy brain
With your baby’s brain developing rapidly throughout pregnancy, a good supply of iodine is essential to building this complex organ2.
A well-balanced diet that includes a healthy intake of iodine will support your baby’s developing brain, contributing to their learning and motor skills, and helping to set the stage for all future development.
Which contains more iodine, organic cows’ milk or regular cows’ milk?
Correct answer
Regular milk contains an impressive 50-80mcg of iodine per 200ml serving.
Incorrect answer
Organic milk only contains 30-65 mcg of iodine per 200ml serving.
Guidance on how much iodine to eat when pregnant
Despite being present in many foods, a 2013 study found that iodine3 deficiency is a public health concern.
The Reference Nutrient Intake (RNI – the amount considered to be enough to meet most people’s needs) for women is 140mcg per day. The World Health Organization recommends that pregnant women get 250mcg per day4.
White fish is an excellent source of iodine, as are dairy foods, including yogurt. It’s worth noting that the iodine content of dairy varies depending on the season, due to variations in how cows are fed throughout the year. Higher levels of iodine have been measured in milk over the winter when cows are fed on winter feed rations, compared with the summer, when lower levels have been measured5. These seasonal changes have been linked to the amount of iodine in maternal diets6. Because the best sources are animal-based, vegetarians and vegans may be at a higher risk of deficiency3. Talk to your midwife about taking a pregnancy-safe iodine supplement4 if you think you might not be getting enough in your diet.
You can also increase your intake by replacing your regular salt with an iodised version. However, you shouldn’t increase your salt intake just to get more iodine. Iodised salt is just a fortified version3.
Foods containing iodine4:
| Food | Portion | Average nutrient quantity (mcg) |
|---|---|---|
| Cow's milk | 200ml | 50-80 |
| Organic cow's milk | 200ml |
30-65 |
| 150g | 50-100 | |
| Eggs | 1 egg | 20 |
| Cheese | 40g | 15 |
| White fish | 100g | 115 |
| Oily fish | 100g |
50 |
| Shellfish | 100g |
90 |
| Meat | 100g |
10 |
| Poultry | 100g |
10 |
| Nuts | 25g | 5 |
| Bread | 1 slice | 5 |
| Fruit and veg | 1 portion | 3 |
NEXT STEPS
Boost your intake with the following iodine-rich meals and snacks:
- Kedgeree made with white fish and boiled eggs
- A bowl of
yogurt with sliced almonds - Prawn cocktail made with
yogurt - Jacket potato topped with cottage cheese or sardines
- A mug of hot milk before bedtime
Last reviewed: 18th August 2014
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