Nature's Own High Strength Magnesium (350 mg elemental per tablet)
One tablet gives you 350 mg of magnesium. Most of it adds up (93 %). It costs $0.075 per 100 mg at the RRP.
mostly adds up · 93 % no testing claim found
Compare with another productMagnesium blends (mixed compounds): all 7 compared
What the brand’s product page says
- Compound, as written
- “Heavy magnesium oxide 515.46 mg (Equivalent: magnesium 300 mg); Magnesium amino acid chelate 125 mg (Equivalent: magnesium 25 mg); Magnesium citrate nonahydrate 217.39 mg (Equivalent: magnesium 25 mg)”
- Compound per serve
- 857.9 mg in total across 3 compounds, listed below
- Magnesium per serve
- 350 mg
- Serve
- 1 tablet, 150 serves per pack, tablet
- Compounds listed
- Heavy magnesium oxide: 515.46 mg (stated as 300 mg magnesium)
- Magnesium amino acid chelate: 125 mg (stated as 25 mg magnesium)
- Magnesium citrate nonahydrate: 217.39 mg (stated as 25 mg magnesium)
- Register entry
- AUST L 394052 · ARTG entry (opens in a new tab)AUST L: listed on the national register of medicines (ARTG). Its ingredients and claims come from approved lists. The TGA, the regulator, didn’t evaluate this product itself before sale.
- Read from
- Nature's Own product page (opens in a new tab) (brand site), read 27 Oct 2026
How much of the compound is magnesium
Only part of each compound is magnesium. Here’s that share for each one. Some compounds come in several versions, for example with water in the crystals. Each version has its own share.
- Heavy magnesium oxide: 60.3 % magnesium
- Magnesium amino acid chelate: no standard share. With no amino acid named, it could be any of several compounds, each with its own share.
- Magnesium citrate nonahydrate: 11.9 % magnesiumThe brand’s product page names this version (“nonahydrate”), so we use its share.
Our maths
Heavy magnesium oxide 515.46 mg → about 310.8 mg magnesium ✓
Show the chemistry
515.46 mg × 0.603 = 310.8 mgVersion used: magnesium oxide (MgO, molar mass 40.30 g/mol), share 0.603. reference (opens in a new tab)
Magnesium amino acid chelate 125 mg → can’t work out: no standard share
Show the chemistry
The stated 25 mg from 125 mg would mean a share of 0.2.
Magnesium citrate nonahydrate 217.39 mg → about 25.8 mg magnesium ✓
Show the chemistry
217.39 mg × 0.1189 = 25.8 mgVersion used: trimagnesium dicitrate nonahydrate, share 0.1189. (worked out from standard atomic weights)
Other versions: trimagnesium dicitrate, anhydrous 0.1616; magnesium citrate 1:1, MgHC6H5O7, anhydrous 0.1134.
Total: can’t be worked out
Do the figures agree?
Heavy magnesium oxide: stated 300 mg, our maths 310.8 mg (-3.5 %) ✓Magnesium amino acid chelate: stated 25 mg; can’t check, no standard shareMagnesium citrate nonahydrate: stated 25 mg, our maths 25.8 mg (-3.3 %) ✓parts add up to 350 mg = stated total 350 mg ✓checked: 325 of 350 mg = 93 %mostly adds up · 93 %
Mostly. The brand’s product page gives a weight and a magnesium figure for each of the 3 compounds. The magnesium figures add up to the stated 350 mg. We can check 2 of them, and each is within 15 % of our maths. Together they’re 325 mg, or 93 % of the magnesium. The other 25 mg is from a chelate, and only the brand knows its exact make-up. Why it matters to you: most of the magnesium behind the cost per 100 mg rests on figures that agree. The rest rests on the stated figure alone. It isn’t a lab test of what’s inside.
Third-party testing
no testing claim found
No testing claim or certificate on the brand’s product page. That’s true of most products here, and it isn’t a mark against this one. The TGA doesn’t check each product before it goes on sale. If batch testing matters to you, ask the brand.
Our note: The Chemist Warehouse listing’s ‘rigorously tested’ names no outside tester, and the brand’s page is silent on testing. A general look for HASTA (Human and Supplement Testing Australia) or Informed Sport listings found none; we haven’t looked by brand yet.
Prices, and what the magnesium costs
Prices are the recommended retail price (RRP), or the regular shelf price where no RRP is shown. Sale and member prices aren’t used, so you may pay less.
Price used: RRP $39.49 · 150 tablets · Chemist Warehouse · 27 Oct 2026.
$39.49 ÷ 150 serves = 26.3c a tablet26.3c ÷ 350 mg × 100 = $0.075 per 100 mg of magnesiumWe use the stated magnesium, not our maths, because that’s the figure you’re given. The price used is the lowest current RRP or regular price we’ve seen, at any shop. The list starts with the lowest current cost per 100 mg; earlier prices follow. Rows marked “Earlier observation (price type not recorded)” were seen up to 27 Oct 2026, before we switched to RRP. Some were sale prices. They stay here, greyed, as history, and no figure uses them.
| Retailer | Price type | Price and pack | Per serve | Per 100 mg | Seen | Note |
|---|---|---|---|---|---|---|
| Chemist Warehouse (opens in a new tab)price used above | RRP | $39.49 for 150 tablets | 26c | $0.075 | 27 Oct 2026 | Page prints "Don't Pay RRP $39.49" and '$9.50 Off RRP'; selling price shown was $29.99 (not used). |
| Chemist Warehouse (opens in a new tab)not used | Earlier observation (price type not recorded) | $29.99 for 150 tablets | not used | not used | 26 Oct 2026 | 'Don't Pay RRP $39.49', '$9.50 Off RRP'; sale price. |
Notes
The Chemist Warehouse listing gives the same magnesium figures but no compound weights; the brand’s page directs 1 tablet daily with food. Its ARTG entry, 394052, was active, opened 27 Oct 2026.
Corrections
- 27 Oct 2026: Label figures changed. Label source changed from the Chemist Warehouse listing (Chemist Warehouse listing, 150 tablets (opens in a new tab)) to the brand's own product page (Nature's Own product page (opens in a new tab)), read 27 Oct 2026, which also states compound weights: heavy magnesium oxide 515.46 mg, magnesium amino acid chelate 125 mg, magnesium citrate nonahydrate 217.39 mg. Previously no compound weights were stated (read 27 Oct 2026). Magnesium figures unchanged: 300, 25 and 25 mg.
Sources we opened
- Chemist Warehouse listing, 150 tablets (opens in a new tab)
- Nature's Own product page (opens in a new tab)
Added 26 Oct 2026. Figures last read 27 Oct 2026.