For this blog, I want to talk all about a topic that can be quite confusing – what are the recommendations for supplements during pregnancy.
Most of the time, the overall guidelines for a healthy and balanced diet are that we should aim to get the majority of our nutrition from food sources rather than supplements. However, there are always exceptions and, in some situations, supplements can be a really useful way to ensure we’re meeting requirements for certain nutrients that might be harder to get from food. When it comes to pregnancy, there are a few supplements that are recommended to take both before and during pregnancy. To help make sure we aren’t missing out on vital nutrients that a baby needs to grow and develop.
Hopefully in this blog, I can help clear up some of the confusion around what nutrients are particularly important during pregnancy and what we should look for when it comes to supplements. It’s quite a lot of information but I’ve also included a table at the end which breaks down the key nutrients to look out for, where they’re found in the diet and when you might need to supplement.
Two Important Supplements
Firstly, let’s take a look at what the current recommendations are for supplements during pregnancy. There are two supplements that are recommended for all pregnant women:
- Vitamin D: In the UK, it’s recommended that (especially during the winter months) everyone takes a supplement of vitamin D. This is because we don’t have access to much sun and, additionally, there are only a few foods that actually contain a decent source of vitamin D. For pregnant women, a daily Vitamin D supplement of 10mg is recommended throughout the pregnancy, regardless of the time of year. To read more about vitamin D, see my blog here.
- Folic Acid: Women who are trying to conceive AND those who are pregnant are recommended to take 400micrograms of folic acid until the 12th week of pregnancy. This is to prevent neural tube defects, which can result in a foetus’ spine not developing properly.
What about other recommendations during pregnancy?
Ultimately, during pregnancy there are a few foods that women are recommended to avoid. But mostly the general recommendation is to follow a healthy, well-balanced diet, in line with the rest of the population. However, there are certain micronutrients that are particularly important during pregnancy and where requirements are actually higher than for the rest of the population. For most of them, it is possible to get them purely from our diets but a supplement can be a helpful way to ensure you’re getting what you need if you’re concerned that you’re not getting enough.
For the rest of this blog I want to highlight exactly which nutrients to look out for and when you might want to consider a supplement. An important thing to note; talk to your GP, midwife or pharmacist if you’re taking multiple supplements. Or if you’re taking other medications, to ensure there’s no unintended side effects or that they don’t contain components that you should avoid during pregnancy.
Folic Acid


As noted above, a daily supplement of 400mcg folic acid is recommended from when you decide to start trying for a baby and throughout the first 12 weeks of pregnancy. Folate (the natural form of folic acid) recommendations are slightly higher during pregnancy so it’s also good to increase your intake of folate-rich foods to meet this. Folate can be found in leafy green vegetables, brown rice and fortified cereals.
Folic acid is important for the development of the baby’s spine and in the prevention of neural tube defects (NTDs). It can be difficult to get the recommended amounts purely from food, which is why a supplement is recommended. In certain cases, a higher dose of folic acid (5mg vs 400mcg) may be advised. This includes if you or the baby’s father have a history of neural tube defects, if you have diabetes or if you take anti-epileptic medicine. If this applies to you, you should discuss the need for a higher dose supplement with your GP.
Iron


Iron is a particularly important nutrient during pregnancy. Extra iron is necessary to support the normal growth of the baby as well as supplementing the iron lost during childbirth. However, as the body adapts to absorb iron more efficiently from foods and there is no menstruation, there are currently no formal guidelines in the UK for iron supplementation or an increase in iron requirements. In some cases, particularly if your iron stores were low before pregnancy, an iron supplement might be recommended. Interestingly, the WHO do recommend a 30-60mcg daily supplement of iron, but this is currently not reflected in UK recommendations.
If you’re unsure about your iron status or have any symptoms of iron deficiency anaemia (including tiredness / lack of energy, shortness of breath, noticeable heartbeats, pale skin), you can discuss with your GP and have a blood test to check your iron levels.
In terms of iron from food, good sources include red meat, eggs, green leafy vegetables, sesame seeds, nuts and pulses. Generally, iron from plant-based sources is absorbed slightly less efficiently, so if you don’t include animal products in your diet, make sure you’re including lots of iron-rich foods. Vitamin C also helps with the absorption of iron from plant-based sources so it’s helpful to include a source of Vitamin C (e.g. tomatoes, peppers, oranges) at the same time.
Iodine


Another key nutrient to consider during pregnancy is iodine. A mineral that contributes to the development of a baby’s brain during pregnancy. It is both possible to have too little and too much iodine so it’s important to be aware of your intake and whether a supplement is necessary.
The requirement for iodine is slightly higher during pregnancy. Generally speaking, you should be able to get enough from a varied and balanced diet. However, most iodine-rich foods are animal products, such as dairy, eggs and fish (especially white fish). So if you don’t include these in your diet, you may be at increased risk of deficiency and should consider supplementing.
Seaweed can be a source of iodine, but it’s quite concentrated and so it’s not recommended more than once per week during pregnancy. Or you could end up exceeding the required amount. Plant-based milks are not always fortified with iodine so if you do consume these regularly, check the label to see if they are.
A pregnancy supplement should contain no more than 150mcg of iodine, and should be in the form of “potassium iodide” or “potassium iodate.” The additional ~50mcg can be made up through your diet. It might be helpful to discuss supplementation with your GP if you have a history of thyroid disease, have had long-term iodine deficiency or are taking other medication.
Vitamin D


Here in the UK we are not particularly blessed with abundant sunshine. Therefore, as a population we are at a higher risk of not meeting our Vitamin D needs. An adequate supply of Vitamin D is necessary for calcium and phosphate regulation. This promotes muscle and bone health. It is important for all adults to be consuming 10ug of Vitamin D per day and this applies during pregnancy too.
Vitamin D is only found in a small number of foods (including oily fish, eggs and red meat). Therefore for the general population as well as pregnant and breastfeeding women, a 10mcg supplement is recommended.
10mcg is equivalent to 400iU, so look out for this on supplement labels.
Calcium


The recommended daily intake for calcium for all adults is 700mg which does not change during pregnancy. Calcium is vital for the development of the baby’s teeth and bones. Despite high calcium demands on the mother, the body naturally adapts to meet these needs. However, as Vitamin D supply promotes the absorption of calcium, it’s really important that Vitamin D requirements are met in order for calcium to be absorbed effectively. Calcium rich foods include dairy products, green leafy vegetables, tofu and fortified soya drinks.
Omega 3 Fatty Acids


Omega-3 fatty acids are essential for the baby’s nerve development as well as a healthy blood and heart. There are currently no UK recommendations for omega-3 intake, but consuming 1-2 portions of fish per week (one of which should be oily) is recommended. Good fish sources of omega-3 include mackerel, sardines, trout and salmon. While plant-based sources include walnuts, flaxseeds and tofu. If you do opt for a supplement, the equivalent dose is around 450mg EPA and DHA per adult daily dose (Reference: BDA). It is important to make sure that the supplement you’re taking doesn’t contain Vitamin A as this can harm the baby and should be avoided during pregnancy.
What else do I need to be aware of?
Vitamin A
An excess of Vitamin A is not recommended during pregnancy and could be harmful to your baby. If you’re taking a multivitamin during pregnancy, make sure that it doesn’t include vitamin A (may be labelled as retinol) and avoid taking a cod liver oil supplement. Additionally, pregnant women should avoid liver or liver pate as this is a particularly concentrated source of vitamin A.
Vegan / Vegetarian diets
Overall, well-planned vegan and vegetarian diets are perfectly healthy during pregnancy. There are however, some nutrients, that can be harder to get in sufficient amounts from plant-based sources. Including iodine, iron, omega-3 fatty acids and vitamin B12. If you’re concerned that your intake might be low and are unsure whether to supplement, you can discuss with your GP, pharmacist or midwife.
Finding out what are the recommendations for supplements during pregnancy is really important information for you to use, moving forwards with your pregnancy. To condense all of this information into one (hopefully) straightforward source, the table below should help you identify where requirements are higher in pregnancy and when you might want to think about a supplement.

