Sarah Keogh, CORU Registered Dietitian
February 2024
Supplements are everywhere, and it is easy to get confused about what you do or don’t need. In an ideal world, a healthy diet will give you all of the nutrition that you need. But sometimes your diet can need some extra help. So where do you start?
Coeliac disease can cause low vitamin D, low vitamin B12, low zinc, low iron, and low levels of other B vitamins. This is often seen when you are diagnosed. This is because you have not been absorbing all of your nutrients, often for years. Once you are diagnosed, and your gut starts to heal, you will start to absorb these nutrients again. However, lots of people with coeliac disease can still have problems with some nutrients even once they are on a strict gluten free diet.
What supplements and when?
Lots of you will need a supplement around the time you are diagnosed with coeliac disease. This is to help get vitamin and mineral levels back up to normal. After a few months, once your gut is healed, you don’t usually need a lot of supplements. It is important to talk to your dietitian about what supplements you need. Important ones are:
Vitamin D: lots of people are diagnosed with coeliac disease because they were found to have low vitamin D levels. In fact, anyone with a low vitamin D level should be checked for coeliac disease. It is a good idea to start a supplement of vitamin D of 15 micrograms per day for adults and 5-10 micrograms per day for children, depending on their age. This is good advice for everybody, not just people with coeliac disease. However, although official advice is to take vitamin D during the Winter, for people with coeliac disease it is best to take vitamin D all year round.
Iron: If you had low iron when you were diagnosed, you would need an iron supplement. Again, speak to your dietitian about the best iron for you. You need to take an iron supplement for three to six months and then recheck your iron levels. If your iron levels are back to normal (both your haemoglobin and your ferritin) then you can stop the iron supplement. However, it is really important to check your iron levels again in three to six months to make sure that your iron levels stay up once you are finished with your supplement. If your iron levels fall again, you may need to check that you are avoiding all gluten or get your diet checked to make sure you are eating enough high-iron foods.
Vitamin B12: This is another vitamin that is often low in coeliac disease and it can make you feel really, really tired. If you had low B12 when you were diagnosed it is also a good idea to take a B12 supplement for a few months. Other B vitamins can be low, so a B complex supplement that contains B12 can be very useful. Again, after a few months you can usually stop the supplement and just focus on your food. Your gut should be back absorbing your B vitamins again.
Calcium: Osteoporosis is a big problem for people with coeliac disease. People who are coeliac will often get more osteoporosis and at a younger age than everybody else. A balanced diet with plenty of milk, yoghurt and cheese is important as well as protein like beans, lentils, fish, chicken, eggs and meat. Lots of people with coeliac disease are lactose intolerant for the first few months after diagnosis. This means that they can struggle to get all of the calcium that they need. Cheese is low in lactose and lactose free milk is a great alternative. However, if you are struggling with your calcium, talk to your dietitian about a suitable supplement.
Zinc and other B vitamins can be low in people with coeliac disease when they are diagnosed. Zinc is not often measured and usually, levels do come back up on their own once you start a strict gluten free diet. However, a general multivitamin for the first few months may be helpful as you get used to your new diet. A multivitamin will have vitamin D, B 12 and other nutrients in it, but you will often need extra iron or calcium if these nutrients are a particular problem for you.
Finding gluten free supplements:
Most supplements are gluten-free, but it doesn’t always say that on the label. It is best to check the product you are using says “gluten free”. If you are not sure ask your dietitian or contact the Coeliac Society at info@coeliac.ie for more advice.
Do you need to buy expensive supplements?
There are hundreds of different supplements that you can buy – so how do you know which one to get? It helps if you know that cheaper supplements are often just as good as more expensive brands. The trick is to read the label.
For a general multivitamin: Check that it has all of the vitamins – from vitamin A to vitamin E, check that it has lots of the minerals – iron, zinc, magnesium and so on. It doesn’t have to have 100% of what you need – a general supplement should be a top-up to your food, it’s not a replacement! There is no need to spend €40-50 on a multivitamin when you can get good versions for €8 in your local supermarket or pharmacy.
Buying individual vitamins? Just check that the supplement you are buying has the amount recommended by your dietitian. The cheaper ones are just as good – and you can check with your pharmacist or dietitian for cheaper alternatives.
Food First
Although you may need some supplements around the time you are diagnosed with coeliac disease, most people don’t need to take supplements all the time – with the exception of vitamin D. If you are not sure if you are getting what you need from your food, do speak to your dietitian who can guide you. You can book an appointment with the dietitian at the Coeliac Society at www.coeliac.ie or call the office.