What are dietary supplements?

Dietary supplements are products that provide nutrients that might be missing from your diet. They are also known as food supplements or nutritional supplements. 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)
• herbal supplements (such as turmeric or raspberry leaf tea)

Dietary supplements are very popular. While supplements have benefits for some, most people do not need them. Eating a balanced diet should give your body all the nutrients it needs. Sometimes, a health professional may ask you to consider supplementation.

If you are thinking about taking supplements, talk to your doctor or pharmacist first. While dietary supplements aren't classified as drugs, they can still cause harm, such as allergic reactions or other side effects.

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 for a certain period of time. For example, if you are pregnant, you might need to take supplements during parts of your pregnancy, until your baby is born, or until you finish breastfeeding. An example is folate (also known as folic acid). This is a B group vitamin that is usually recommended from one month before you become pregnant and for the first 3 months of pregnancy.

Your doctor may suggest that you take a supplement because you have a deficiency. They will measure the levels of the nutrient in your body using a blood test. They will tell you when you can stop taking the supplement, for example once your levels are in the normal range.

In some other cases, you might need to take a supplement for a longer period. This could be because you have a chronic (long-term) health condition.

Who needs supplements?

There are some people who find it hard to get the nutrients they need through diet alone. Your doctor or dietitian may recommend a supplement if they think you could benefit from it.

You might need to take a supplement if you:

• are pregnant or breastfeeding
• aren't getting enough nutrition from the food you eat (malnutrition)
• 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)
• are taking a medicine that affects certain dietary nutrients
• have a health need for a particular nutrient (for example, if you are at risk of osteoporosis and need more calcium)
• have a restricted diet (for example, if you don't eat meat and aren't getting enough iron)
• have a nutritional deficiency (for example, a blood test shows you have a vitamin D deficiency)

Many people who take supplements don't need them, because they are getting enough nutrients from their diet already.

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 and may be dangerous.

Here are some examples:

• Large doses of vitamin B6 can damage the nervous system.
• Taking too much vitamin A or E in the form of supplements while you are pregnant can cause serious harm to your baby.
• Supplements can have side effects or interact with other medicines, making them dangerous or less effective.

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

In Australia, the Therapeutic Goods Administration (TGA) regulates the sale of 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. Examples of nutrients and their food sources include:

• iron: red meat, nuts and legumes
• folate: green leafy vegetables, cereals and bread, fruit and nuts
• iodine: seafood, milk and vegetables
• potassium: green leafy vegetables, beans and peas, bananas
• magnesium: green vegetables, shellfish and spices

Learn more about dietary vitamins and minerals.

You can get advice about the right amounts and types 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 for a referral to a dietitian.

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

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.

You can also find further information online about dietary supplements:

• The eatforhealth.gov.au website has information on individual nutrients and their recommended daily intake.
• The Food Standards Australia New Zealand (FSANZ) website has resources on dietary nutrients and safety of supplements.
• Nutrition Australia offers tips and resources to eat a balanced and healthy diet.

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).

Languages other than English

The Health Translations website has information on the Australian guide to healthy eating in languages other than English.

Information for Aboriginal and/or Torres Strait Islander peoples

View the Aboriginal and Torres Strait Islander guide to healthy eating at The Australian Indigenous HealthInfoNet.