What are dietary supplements?

Dietary supplements (also called food supplements or nutritional supplements) are products designed to give you nutrients that might be missing from your diet. They are usually taken as tablets, capsules or powders, or as a liquid drink.

Some common examples of supplements include vitamins and minerals (such as vitamin C, iron and calcium), oil supplements (such as fish oil capsules) and herbal supplements.

Dietary supplements are very popular with Australians. While supplements have benefits for some, most people do not need them. If you are thinking about taking supplements, talk to your doctor or pharmacist first as some dietary supplements can cause harm, such as an allergic reaction.

Why use supplements?

If your diet lacks a particular nutrient, you might need a supplement to fill that gap.

Often, you will only need to take a supplement temporarily. For example, if you are pregnant, you might need to take supplements for part of your pregnancy, until your baby is born, or until you finish breastfeeding. Folate (folic acid – a B group vitamin) is usually recommended one month before you become pregnant and for the first 3 months.

In some other cases, you might need to take a supplement for a longer period of time, including if you have a chronic health condition.

Who needs supplements?

Many people who take supplements don’t need them, because they are getting enough nutrients from their diet already. Still, almost 1 in 2 Australians take a dietary supplement.

There are some people who find it hard to get the nutrients they need through diet alone, and if your doctor or dietitian recommends it, you may benefit from a supplement. You might need to take a supplement if:

• you are pregnant or breastfeeding
• you are older, and aren't getting enough nutrition from the food you eat (malnutrition)
• you have a health condition that means your body cannot absorb the nutrients it needs (for example, if you have chronic kidney disease and are on dialysis)
• you have a strong need for a particular nutrient (for example, if you are at risk of osteoporosis and need more calcium)
• you have a restricted diet (for example, if you don't eat meat and aren't getting enough iron)
• you have a nutritional deficiency (for example, a blood test shows you have a vitamin D deficiency)

What are the risks of using supplements?

While your body needs a certain amount of each nutrient, higher amounts are not necessarily better. In fact, getting more than you need can sometimes cause harm.

For example, large doses of vitamin B6 can damage the nervous system, and taking vitamin A, C, or E supplements while you are pregnant can cause serious harm to your baby. Some supplements can also interact with other medicines you are taking, making them dangerous or less effective.

Make sure to tell your doctor or nurse of any dietary supplements you are taking together with your medicines, especially if you are in hospital or before any surgeries.

Dietary supplements can have side effects or interact with other medicines, and may be dangerous in overdose. In Australia, the Therapeutic Goods Administration (TGA) regulate all vitamins for safety and quality. Be especially careful when buying dietary supplements from overseas. The best way to make sure any supplements you plan to take are safe, is to check with your pharmacist or doctor.

What is the alternative to supplements?

The best way to get all the nutrients you need is to eat a balanced and varied diet. Some nutrient and alternative food examples are:

• Iron: red meat, nuts and legumes
• Folate: green leafy vegetables, cereals, fruit and nuts
• Iodine: seafood, milk and vegetables

You can get advice about the right amount and kinds of foods to eat from the Australian Dietary Guidelines.

Resources and support

If you are worried that you are not getting all the nutrients you need, talk to your doctor or ask a dietitian.

You can also find further information online at eatforhealth.gov.au and the Food Standards Australia New Zealand's (FSANZ) website.

To find a dietitian near you use the healthdirect Service Finder tool.

For information on dietary supplements recommended during pregnancy or breastfeeding, call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436 or video call. Available from 7 am to midnight (AET), 7 days a week (including public holidays).