Bottles of magnesium are priced so you can’t compare them. One has 120 tablets, another has 300. One gives you 105mg of elemental magnesium per capsule, another 160mg. The front of the pack quotes a compound weight that means nothing on its own. Standing in an aisle, there is no way to work out which is better value without a calculator and the fine print on the back.
So I did the arithmetic for five of them.
The number below is cost per 100mg of elemental magnesium: what you actually pay for the magnesium itself, stripped of packaging, tablet counts and marketing weights. It’s the only figure that lets you compare two bottles honestly, and no label prints it.
The table
All five are magnesium glycinate, so this is a fair comparison of the same form. Prices checked in August 2026.
| Product | Elemental Mg | Count | Price | Per 100mg |
|---|---|---|---|---|
| Nature’s Own Magnesium Glycinate 1150mg | 150mg/tablet | 300 | A$44.99 | A$0.10 |
| Healthy Care Magnesium Glycinate | 160mg/tablet | 120 | A$29.99 | A$0.16 |
| Nutra-Life Magnesium Glycinate | 105mg/capsule | 120 | A$22.00 | A$0.17 |
| Swisse Ultiboost Magnesium Glycinate | 150mg/tablet | 120 | A$49.99 | A$0.28 |
| Jigsaw MagPure Glycinate (US import) | 50mg/capsule | 120 | A$42.50 | A$0.71 |
The spread between the cheapest and the dearest is about sevenfold. Same form, same job, seven times the price per unit of magnesium.
The part that costs me money
The bottom row is the one on my shelf. I’ve written a review of it and I’ve been taking it for months, and it is the worst value on this table by a wide margin.
That is uncomfortable to publish on a site that earns a commission when someone buys it, so I want to be exact about it. You pay about seven times more per milligram of magnesium buying MagPure than buying Nature’s Own at a Chemist Warehouse. That part isn’t arguable; it’s division.
So I went looking for what the number leaves out, expecting to find that the cheap ones were cutting corners.
Mostly they aren’t. Pure magnesium bisglycinate is 14.1% elemental magnesium, and that figure is fixed by the chemistry rather than by the manufacturer. Work backwards from each label and you can see whether the claim is possible: a product implying much more than 14.1% has either a partly reacted material or something else blended in. All three Chemist Warehouse products come out at or below that line, which is what a genuine chelate looks like. On the evidence of their labels they are what they say they are.
There are two real differences, and neither is worth sevenfold on its own.
The ingredient list. MagPure declares three things: the Albion chelate, a vegetable capsule, and vegan L-leucine as an anti-caking agent instead of magnesium stearate. It states no allergens. Nature’s Own publishes its magnesium content and an allergen line that includes sulphites, but the excipients aren’t listed on the retail page at all. That isn’t evidence of anything bad. It is less information.
The chelate is named. Albion is the ingredient supplier most often specified when a formulator wants a fully reacted chelate rather than a blend. The Australian labels say “magnesium glycinate” without naming a source. Again, not evidence against them; just less to check.
What tips it back the other way is dose. MagPure gives 50mg a capsule. Reaching a 300mg daily target means six capsules, which is A$2.13 a day. Two Nature’s Own tablets get you there for about 30 cents. Whatever the formulation is worth, it is not worth seven times, and the capsule count is the reason the gap is so wide.
So why am I still buying it
Because of how I got here, which is a different thing from the numbers above.
I spent a few years reading Morley Robbins, who runs the Magnesium Advocacy Group and gets called the Magnesium Man. His work is where a lot of my early interest came from, and Jigsaw is the brand I associated with him. That’s how the bottle ended up on my shelf, and habit did the rest.
Two things I should say about that.
Robbins appears in Jigsaw’s own marketing, on their blog and in a video series they host. I don’t think that makes his position insincere, but it does mean the recommendation I acted on came partly through a channel the seller controls. I didn’t weigh that at the time. I should have, and I’m noting it here because I’d expect it of anyone else writing this page.
And his Root Cause Protocol, the wider framework the magnesium sits inside, hasn’t been tested in the kind of trials I’d want before repeating its claims. The copper and iron biochemistry underneath it is real and well established. The protocol built on top of it is not the same thing as the biochemistry, and I’m not going to blur those two together on a site that spends the rest of its time being careful about exactly that.
So: I take it, I’ll probably keep taking it, and none of that is an argument that you should. If you want the same form for a fifth of the price, the top of that table is where I’d point you.
What I won’t do is pretend the price difference isn’t real, or bury it three clicks away from the affiliate link.
Why the gap is so wide
Two things, mostly.
Dose per unit. MagPure gives 50mg of elemental magnesium a capsule. Nature’s Own gives 150mg a tablet. Before price enters the picture, you need three MagPure capsules to match one of theirs, which triples the effective cost of a daily dose.
Import. Jigsaw ship from the United States. The A$42.50 above is the converted list price and doesn’t include postage, which pushes the real gap wider than the table shows.
Neither of those makes the product bad. They make it expensive.
Before you just buy the cheapest one
The arithmetic gives you value per milligram. It doesn’t answer everything, and a few things sit outside it.
Tablet size. Getting 150mg of elemental magnesium from glycinate needs over a gram of compound, so those tablets are large. Some people find them difficult to swallow, and a cheap tablet you don’t take is worse value than an expensive capsule you do.
What else is in it. Elemental magnesium per unit tells you nothing about excipients, binders or fillers. Compare ingredient lists as well as numbers.
Whether the price is real. Two of the products above were discounted when I checked: Nature’s Own to A$29.99 from A$44.99, Swisse to A$24.99 from A$49.99. I’ve used the regular prices in the table, because a sale price flatters a product for as long as the sale lasts. At sale prices the ranking shifts, which is exactly why “50% off” tells you very little on its own.
Best for: working out which bottle on a shelf gives you the most magnesium for your money, before any other consideration.
How to do this yourself
Two steps, and it works on any bottle in any shop.
- Total elemental magnesium in the bottle = elemental mg per tablet x number of tablets
- Cost per 100mg = price / that total, x 100
Nature’s Own: 150 x 300 = 45,000mg for A$44.99, which is A$0.10 per 100mg. MagPure: 50 x 120 = 6,000mg for A$42.50, which is A$0.71 per 100mg.
The whole comparison is on the back of the bottle. It’s just never presented in a form you can use.
Sources: product labels and prices as displayed by Chemist Warehouse, August 2026 (https://www.chemistwarehouse.com.au/); Jigsaw Health MagPure Glycinate supplement facts panel (https://www.jigsawhealth.com/products/best-pure-magnesium); magnesium glycinate formula C4H8MgN2O4, PubChem CID 84645 (https://pubchem.ncbi.nlm.nih.gov/compound/Magnesium-Glycinate), from which the 14.1% elemental figure is calculated; NIH Office of Dietary Supplements: Magnesium Fact Sheet (https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/)
This article is general information, not medical advice. Prices change; check current prices before buying. Speak to a doctor or pharmacist before starting a supplement, especially if you take other medication or have kidney problems.