Supplements for IBS and diarrhoea: a nutritionist's review

While I always advocate simple changes to diet and lifestyle to minimise symptoms of IBS including diarrhoea, sometimes supplements can support.

A national newspaper asked me about supplements that could help people with IBS and diarrhoea. I always put food at the top of my advice to clients, but targeted supplementation can be a helpful addition as long as it's done safely.

I was pleased to see this media article incorporate my important caveat about supplements. It's important to see your GP, clinical nutritionist or dietitian before taking supplements for IBS, and review this together every three months. Evidence from the global authority on cancer prevention, the World Cancer Research Fund, shows that some high-dose supplements can increase cancer risk. So don’t rely on them to treat IBS or any other digestive health condition or symptom. Always aim to boost your vitamins and minerals through food sources where you can, and seek professional advice. As a tertiary-qualified, accredited clinical nutritionist, I'm always happy to help.

From Vitamin D to probiotics, here's my review. Read the full article here.

1. Vitamin D

Our body needs sunshine to make vitamin D, so supplementation is recommended by health professionals in autumn and winter months - even in Australia, especially in cities like Melbourne. Many people with IBS are found to have low levels of Vitamin D in their blood. Supplementation with Vitamin D may support symptom management. f you have IBS with diarrhoea, try a supplement containing a safe dose of 10 ug/d (400 IU).

2. Zinc

Our gut plays an important role in immunity, and zinc may help boost immune function. It may also improve diarrhoea after a bout of gastroenteritis. Choose a liquid supplement to maximise absorption and don't take more than 25mg. High doses can cause anaemia and weakening of the bones (a risk especially as you enter perimenopause or menopause). You can get zinc from shellfish like prawns, lean meat and fortified bread.

3. Probiotics

Probiotics are live bacteria and yeasts that can reduce loose stools, benefit your digestive and your wider health. But don't choose any brand from the shelf. I can advise on strain-specific probiotics for your symptoms - they are especially effective after gastroenteritis. Try probiotics for at least a month to see if they help. If you don't notice any effect, you can try another brand or strain.

4. Lactase

If you have IBS with diarrhoea, you may also be lactose intolerant. Your small intestine can't produce enough of the lactase enzyme in this situation, causing problems digesting milk, some cheeses and yoghurts. This can lead to bloating, diarrhoea and wind. See your GP to get tested for lactose intolerance, or contact the pip nutrition clinic for advice. You can then try adding lactase drops to milk, or drink lactose-free milk - easily available at the supermarket, it is still high in important calcium.

And one to avoid: Vitamin C

Vitamin C's role is to protect our body's cells and help us heal quickly. But too much can make diarrhoea much worse. Avoid supplements over 1,000mg per day if you have IBS or diarrhoea.