Folic acid, iodine and vitamin D

A healthy diet is important during pregnancy. But you can’t always get everything that you and your baby need from food. Find out about folic acid and iodine tablets and how to get enough vitamin D.

Supplements during pregnancy
Folic acid

Folic acid helps the body to make new cells. Folic acid is important because it can help to prevent birth defects of a baby’s brain and spine, such as spina bifida. Spina bifida can cause walking, bladder and bowel problems.

Take a folic acid tablet (0.8 milligram [mg]) every day for 4 weeks (1 month) before you might become pregnant through to 12 weeks after becoming pregnant.

If you find out that you are pregnant and you haven’t been taking a folic acid tablet, start taking tablets straight away. Keep taking them until the 12th week of your pregnancy.

You can buy folic acid tablets from pharmacies (or at a lower cost when prescribed by your midwife, medical practitioner or nurse practitioner - talk to them to find out more.)


Iodine helps the body to grow and develop, especially the brain. Because babies get iodine from their mothers, pregnant and breastfeeding women need more iodine.

During pregnancy and while breastfeeding, choose foods that are high in iodine and take an iodine tablet every day. Foods that are high in iodine are well cooked seafood, milk, eggs, some cereals and bread.

Take one 0.150 milligram (mg)/150 micrograms (mcg or μg) iodine-only tablet every day when pregnant and breastfeeding. You can buy iodine tablets at pharmacies (or at a lower cost when prescribed by your midwife, medical practitioner or nurse practitioner - talk to them to find out more.)

Vitamin D

Vitamin D is needed for strong bones and joints as well as healthy muscle and nerve activity. If you don’t have enough vitamin D during pregnancy, your baby may be born with low vitamin D levels. This can affect how your baby develops.

The sun is the main source of vitamin D. Small amounts of vitamin D can also be found in foods such as oily fish (tuna, sardines and salmon), eggs and some margarines, milks and yoghurts.

Some time in the sun is recommended so that your body can make vitamin D. Try to get outside before 10 am or after 4 pm between September and April, and around the middle of the day between May and August. The lighter your skin, the less time you need to be in the sun to make enough vitamin D. Don’t get sunburnt!

Some people have low levels of vitamin D – called vitamin D deficiency. If you have darker skin, spend most of your time inside, have liver or kidney disease or are taking certain medicines (eg, anticonvulsants), you are at a higher risk of vitamin D deficiency. If you live south of Nelson-Marlborough in winter, you’re also more likely to have low vitamin D levels in late winter and early spring.

If you are worried that you don’t get enough vitamin D, or you have a higher risk of vitamin D deficiency, talk to your midwife, medical practitioner or nurse practitioner.

Related websites

Folic acid and spina bifida/iodine and iodine deficiency – HealthEd (Health Promotion Agency and Ministry of Health)
Advice on reducing the risk of spina bifida (a serious birth defect and the most common type of neural tube defect) by taking folic acid and eating foods containing folate when planning to be pregnant and during pregnancy. Advice on taking iodine supplements when pregnant and breastfeeding.

Eating for healthy pregnant women – HealthEd (Health Promotion Agency and Ministry of Health)
Food information for pregnant women. Includes food for a healthy mother and baby, dietary variety, drinking plenty of fluids, foods low in fat, salt and sugar, keeping active, food safety and listeria, salmonella, campylobacter and toxoplasma, snack and lunch ideas, eating well during pregnancy, indigestion, heartburn, constipation, alcohol, being smokefree, folic acid, iodine and vitamin D.

Food safety in pregnancy – Ministry for Primary Industries
Food safety information for pregnant women, and the most up-to-date list of high-risk foods to avoid. You can also call MPI Food Safety on 0800 693 721.

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