How much magnesium, zinc or iron are you really getting?
Founder of Clean Green Safe
Mineral labels can be genuinely confusing, so please don’t feel you’ve missed something. Choose your mineral and the form on your label, enter the amount, and you’ll see how much of the mineral itself you’re getting each day, alongside the Australian daily target and upper limit.
Daily target: 320 mg · this is 94% of it
Upper limit: 350 mg a day from supplements (food doesn’t count toward this limit) · this amount is close to the upper limit
Why is the number on my label so different?
Minerals always come joined to something else, like oxide, citrate or gluconate. The big number on a label is often the weight of that whole compound. The amount that counts toward your daily target is the mineral itself, called the elemental amount, and it’s usually written as “equivalent to”.
If your label already shows an “equivalent to” amount, that’s the number to use, and you can enter it with the “I already know the elemental amount” option above.
How much zinc is in zinc gluconate?
Zinc gluconate is about 14% zinc. So 50 mg of zinc gluconate gives you about 7 mg of zinc, a little under the 8 mg daily target for women.
How much magnesium is in magnesium oxide or citrate?
- Magnesium oxide is about 60% magnesium, so 500 mg gives you about 300 mg
- Magnesium citrate is about 16% magnesium, so 500 mg gives you about 80 mg
- Glycinates and chelates vary from product to product, so look for the “equivalent to magnesium” line on the label
Our article on the magnesium RDI in Australia explains how much you need each day and why the upper limit is lower than the target.
How much iron is in ferrous fumarate?
Ferrous fumarate is about 33% iron, so a 300 mg tablet gives you about 99 mg of iron. That’s well above the daily target, which is why these doses are usually only recommended for a set time when your doctor has found you need it.
Iron is one supplement I’d always suggest checking with your GP or pharmacist first, and please keep it well out of reach of children. Even a small number of adult iron tablets can be very dangerous for a child.
Three simple checks
- Find the “equivalent to” amount, or use the calculator to work it out from the compound.
- Multiply by the number of tablets or capsules you actually take each day.
- Add up every product that contains the same mineral, including multivitamins.
If you take other medicines, or you’re not sure a supplement is right for you, please have a chat with your pharmacist or GP. We’re always happy to help.
Want to know more about each mineral? Read our guides to magnesium, zinc and iron, or try our vitamin unit converter.
Cassie is a registered pharmacist, a parent and the founder of Clean Green Safe. With a background in Australian supplement regulation across the TGA, FSANZ and NHMRC, she built Clean Green Safe to help people understand what’s really in their supplements, and how it all adds up across everything they take.
How Clean Green Safe can help
You don’t have to do these sums yourself. Scan any supplement and Clean Green Safe works out the elemental amount of every mineral for you, compares it with your daily nutritional target and the Australian upper limit, and adds it up across everything you take.
- STEP 1ScanScan the barcode or enter the AUST L number
- STEP 2CheckWe check it against the TGA register and Australian limits
- STEP 3SeeSee your grade and your daily totals across everything you take
Built by a registered pharmacist · Works in your phone’s browser