Research-supported guide

How to read a supplement label in Australia

The front of a supplement pack is marketing. The rest of the label is regulated, and it carries the information that lets you compare products properly. Here is what each part means and what to check.

Written byGuy StockwellFounder, NTH Health

Published 20 September 2026Last reviewed 20 September 2026

Key takeaways

The equivalent amount of the mineral, not the compound weight, is the figure to compare between products.
Check how many capsules a quoted dose refers to before comparing packs.
Warning statements and directions are mandated with set wording, not marketing copy.
Check every label for other actives, especially vitamin B6, and for declared excipients and allergens.
Labels do not tell you how well a product is absorbed, or whether the evidence for its claims has been assessed.

Why the label matters more than the marketing

The front of a supplement pack is designed to sell it. The rest of the label is regulated, and it is where the information that lets you compare products actually sits.

In Australia, labels for non-prescription medicines have to follow a labelling standard set by the Therapeutic Goods Administration. That standard is the reason different brands carry the same kinds of information in roughly the same places. This guide works through what those parts mean, in the order most people need them.

1. The active ingredients, and the equivalent amount

This is the single most useful part of the label.

Labels must state the active ingredients and how much of each the product contains. Where a medicine contains a mineral for supplementation, the label must also declare the amount of the mineral element, usually written as "equivalent to". So a magnesium product reads something like "magnesium glycinate 1,000 mg, equivalent to magnesium 141 mg".

The second number is the one to compare between products, and the one to check against recommended intakes and upper levels. The first number tells you which form you are buying. Our guide to elemental magnesium works through why the two differ so much and how much each form carries.

Check the dose the numbers apply to, as well. A figure quoted "per serve" can mean two or three capsules, so a pack that looks stronger may just have a larger serve.

2. The AUST number

Every medicine approved for supply carries an AUST R, AUST L or AUST L(A) number. For most supplements it is AUST L, which means the product is listed using pre-approved low-risk ingredients and pre-approved claims, and that the TGA has not assessed the evidence for those claims before sale.

Our guide to what AUST L means covers the differences, and our guide to searching the ARTG explains how to look the number up.

3. Warnings and directions

Warning statements on medicine labels are mandated, with set wording, so they are not marketing copy and they are not optional. If a warning is there, it is there for a reason.

Directions for use tell you the dose the product was designed around. Some magnesium products are meant to be taken in divided doses, which matters, because the proportion of magnesium absorbed falls as the size of a single dose rises. Our explainer on absorption and bioavailability covers that.

4. Everything else in the product

Two kinds of ingredient sit beyond the headline one.

Other actives. Many magnesium products also contain vitamin B6. Too much vitamin B6 can damage nerves, and the amounts add up across products, so the TGA advises checking the label of every supplement you take for it. From 1 June 2027, oral products with more than 50 mg per daily dose will only be available with a pharmacist's advice.

Excipients. These are the other ingredients: fillers, binders, capsule shells, flavours. Labels must declare certain excipients and impurities, including allergens such as egg, sulfites and benzoates. This is the part of the label to read if you have an allergy or avoid particular ingredients.

5. Batch number and expiry date

Labels must carry a batch number and an expiry date. The batch number is what a recall refers to, and what you would quote if you ever reported a problem with a product. The expiry date is straightforward, but worth checking on discounted stock.

6. Storage conditions

Labels must state storage conditions. For most supplements this is a line about storing below a certain temperature and keeping the pack dry. A bathroom cabinet is usually the worst place in the house for both.

7. The sponsor

The label must carry the name and contact details of the sponsor, the company responsible for the medicine in Australia, or a nominated distributor. This is not always the brand on the front. It is who to contact about a problem, and it is also shown on the product's ARTG entry.

What the label will not tell you

Whether the evidence stacks up. On an AUST L product, the claims come from a pre-approved list and their evidence has not been assessed before sale.
How well it is absorbed. No label carries absorption data, and a higher amount of a mineral does not mean more of it is taken up.
Whether it suits you. Interactions with prescription medicines, kidney function, pregnancy and age all sit outside the label. Our guide to side effects and interactions covers those.

A 60-second label check

Find the equivalent amount of the mineral, and the number of capsules that dose refers to.
Check the AUST number and what kind it is.
Read the warnings and directions.
Scan the other actives, especially vitamin B6, and add up anything you take twice.
Check the excipients against any allergies.
Check the expiry date.

If anything is unclear, a pharmacist can read a label with you and check it against your other medicines. Nothing on this page is a substitute for individual medical advice.

Common questions

Questions, clearly answered.

01What does "equivalent to" mean on a supplement label?

It is the amount of the mineral element itself, as opposed to the weight of the compound. Australian labels must declare it for minerals used for supplementation, and it is the figure to compare between products.

02What has to be on an Australian supplement label?

The medicine name and dosage form, active ingredients and quantities, the AUST number, the sponsor's name and contact details, batch number, expiry date, directions for use, storage conditions, the quantity in the pack, and required warning statements and excipient declarations.

03What are excipients on a supplement label?

The ingredients other than the actives, such as fillers, binders, capsule shells and flavours. Certain excipients and allergens, including egg, sulfites and benzoates, must be declared.

04Why should I check a supplement label for vitamin B6?

Vitamin B6 appears in many products, including magnesium supplements, and too much can damage nerves. The amounts add up across everything you take, so the TGA advises checking every label.

05Does a supplement label show how well it is absorbed?

No. Labels carry the amount in the dose, not absorption data. A higher amount of a mineral does not mean more of it is taken up by the body.

Sources

Read the evidence yourself.

Sources are provided so readers can examine the research and official guidance directly.

01 Medicine labels: Guidance on TGO 91 and TGO 92Therapeutic Goods Administration

TGA guidance on the labelling standard for non-prescription medicines. Where a medicine contains a mineral for supplementation, the name and quantity of the mineral element must be declared on the label, for example calcium carbonate with the statement equivalent to calcium 500 mg. This applies to all mineral supplements.

02 How are vitamins regulated in Australia?Therapeutic Goods Administration

AUST L listed medicines are not pre-market evaluated but can only use pre-approved low-risk ingredients and pre-approved indications for minor health conditions. Sponsors should hold evidence of efficacy. Must be made in a certified facility. AUST L(A) medicines have efficacy assessed before sale. The TGA may review products and can cancel them from the ARTG.

03 Are you unknowingly taking too much vitamin B6?Therapeutic Goods Administration

Vitamin B6 is found in a range of products including multivitamins and magnesium, zinc and iron supplements. Advises checking the label of every supplement for vitamin B6.

04 AUST numbers on medicine labelsTherapeutic Goods Administration

All medicines included in the ARTG must show the relevant AUST number on the label. Medicines with AUST R and AUST L(A) numbers are assessed for efficacy. Those with AUST L numbers are not.

05 Magnesium: Fact Sheet for Health ProfessionalsNational Institutes of Health, Office of Dietary Supplements

Magnesium is a cofactor in more than 300 enzyme systems. The 350 mg upper level applies to supplements and medicines, not to magnesium from food. Interactions with bisphosphonates, antibiotics, diuretics and proton pump inhibitors. Toxicity risk rises with impaired kidney function.

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