If you’re pregnant or trying to conceive, you’ve probably heard that you need to take folic acid. You might also have heard something about iodine. But between the different dosages, the “start before you’re even pregnant” advice, and the overwhelming number of supplements on the shelf, it can be genuinely hard to know whether you’re doing the right thing.
So here’s the plain-English version, based on what the Ministry of Health actually recommends for pregnant people in Aotearoa.
Why Folic Acid Matters So Much in Early Pregnancy
Folic acid is a synthetic form of folate, a B vitamin that plays a critical role in the early development of your baby’s neural tube. The neural tube is what becomes the brain and spinal cord, and it forms in the very first weeks of pregnancy, often before many people even know they’re hapū.
That’s why the timing matters so much.
A deficiency in folic acid during this window is linked to neural tube defects such as spina bifida. The good news is that taking folic acid before and during early pregnancy significantly reduces this risk.
How Much Folic Acid Do You Need in NZ?
The Ministry of Health recommends 800 micrograms (mcg) of folic acid per day for most people who are pregnant or trying to conceive. This is a higher dose than what you’d find in a standard multivitamin, so it’s worth checking the label of whatever you’re taking.
A higher dose of 5mg per day is recommended if any of the following apply to you:
- You or your partner has a personal or family history of neural tube defects
- You have diabetes (type 1 or type 2, including insulin-treated diabetes)
- You’re taking certain medications, including some anti-epileptic drugs
- You’ve had a previous pregnancy affected by a neural tube defect
If any of these apply, talk to your LMC or GP about getting a prescription for the higher dose.
When Should You Start Taking Folic Acid?
Ideally, you should start taking folic acid at least four weeks before you conceive, and continue through the first 12 weeks of pregnancy. Because many pregnancies aren’t planned, health guidelines in Aotearoa suggest that anyone who could become pregnant take folic acid as a matter of routine.
If you’ve found out you’re pregnant and haven’t started yet, start now. It’s still worth taking even if you’re past the four-week mark.
What About Iodine? Why Does It Matter in Pregnancy?
Iodine is one of those nutrients that doesn’t get as much attention as folic acid, but it’s just as important for your growing pēpi. Iodine is essential for thyroid function, and your thyroid plays a big role in regulating your metabolism and supporting your baby’s brain and nervous system development.
New Zealand soils are naturally low in iodine, which means the food grown here tends to have lower iodine levels than in some other countries. Iodine deficiency has been identified as a public health concern in Aotearoa, particularly for pregnant and breastfeeding people.
How Much Iodine Do You Need?
The Ministry of Health recommends a daily 150 mcg iodine-only tablet for pregnant and breastfeeding women. Unlike folic acid, you don’t need to start iodine before conception. The recommendation is to begin from confirmation of pregnancy and continue throughout breastfeeding.
Iodine tablets are available at pharmacies, and can be obtained at a lower cost when prescribed by your midwife, GP, or nurse practitioner. The funded brand in NZ is NeuroTabs.
Getting Iodine from Food
Some dietary sources of iodine include:
- Seafood and fish
- Dairy products (milk, yoghurt, cheese)
- Eggs
- Bread (mandatory iodine fortification of non-organic bread via iodised salt has been in place in NZ since 2009)
While food sources can contribute to your iodine intake, it’s generally difficult to meet the higher pregnancy requirements through diet alone, which is why a supplement is recommended in addition to eating well.
Do You Need a Separate Folic Acid Supplement, or Will a Prenatal Vitamin Cover It?
This is where a lot of people get tripped up. The answer depends on what’s in the supplement you’re taking.
Many standard multivitamins don’t contain enough folic acid to meet the 800mcg pregnancy recommendation. Some prenatal vitamins do include both folic acid and iodine at the right doses, but not all of them do.
When you’re looking at supplements, check:
- Folic acid: at least 800mcg (or 0.8mg)
- Iodine: 150mcg
- That you’re not paying for a long list of extras if your diet is already reasonably balanced
Some people also take folate (the natural form) rather than folic acid. There’s growing interest in methylfolate as an alternative, particularly for people with a gene variant called MTHFR that affects how the body processes synthetic folic acid. If this is something you’re curious about, it’s worth discussing with your LMC, midwife, or GP.
A Note on Supplements and Cost in NZ
Folic acid at 800mcg is available over the counter from most pharmacies and health stores in Aotearoa, and it’s generally not expensive. If you need the higher 5mg folic acid dose, this is available on prescription and can be subsidised. It’s worth asking your GP or LMC about this.
Iodine tablets (150mcg) are also available at pharmacies and are subsidised when prescribed. Your midwife or GP can prescribe both if needed, which can make them more affordable.
What About Folic Acid in Food?
Since August 2023, mandatory folic acid fortification of all non-organic bread-making wheat flour has been in place in New Zealand. This means most commercially made bread now contains folic acid. This is a useful contribution to your daily intake, but it’s not a replacement for supplementation, especially given how critical the pre-conception window is.
What If You’re Still in the Planning Stage?
If you’re thinking about trying for a pēpi and haven’t started taking folic acid yet, now is genuinely the best time to start. The neural tube forms so early in pregnancy that waiting until you get a positive test can mean the critical window has already passed.
Starting folic acid before conception is one of the most straightforward things you can do to support a healthy pregnancy before it even begins. Iodine can be added once you have a confirmed pregnancy.
The Short Version
You don’t need to overthink this. Here’s the practical summary:
- Start folic acid at least four weeks before trying to conceive and continue for the first 12 weeks
- Take 800mcg of folic acid daily (or 5mg if your LMC or GP advises it)
- Start a 150mcg iodine tablet daily from confirmation of pregnancy and continue while breastfeeding
- Check your prenatal vitamin covers both at adequate doses
- Both are available subsidised on prescription, so ask your midwife or GP
- If you’re unsure about anything, ask your LMC, midwife, or GP
Taking these two nutrients consistently is a small thing that can make a meaningful difference for your baby’s development, especially in those early weeks when a lot is happening before you even realise it.
Disclaimer: The information in this article is general in nature and is not a substitute for professional medical advice. Every pregnancy is different. Please speak with your LMC, midwife, or GP about what’s right for you and your whānau.