What type of magnesium is best for sport?
Answer
No form carries a sport specific claim, because magnesium claims attach to the mineral at 15 percent NRV or above. The choice is decided by magnesium content, absorption and tolerability at a full serving.
Key takeaways
- Is one form better for sport?
- No form carries a sport claim. The authorised claims attach to the mineral, whichever compound delivers it.
- What decides the choice?
- How much magnesium the compound carries by weight, how well it absorbs, and how comfortable it is at a full serving.
- Which form for daily use?
- Bisglycinate, on tolerability across a season. Oxide is the one to avoid at a full serving.
- What about taurate and threonate?
- Both are marketed on specific outcomes with no authorised claim distinguishing them from any other form.
The claims do not vary by form
This is the point the category works hardest to obscure. Magnesium carries authorised claims for normal muscle function, normal protein synthesis, the reduction of tiredness and fatigue, electrolyte balance, normal energy yielding metabolism and normal nervous system and psychological function.
All of them apply at a serving providing at least 15 percent of the 375mg reference value, and all of them attach to the mineral rather than to a compound. Oxide, citrate, bisglycinate, malate and taurate carry identical claims at identical thresholds.
What actually differs
Three things, and none of them is a claim.
| Form | Magnesium by weight | Absorption | Tolerability at a full serving |
|---|---|---|---|
| Oxide | About 60 percent | Poor | Worst, most associated with loose stools |
| Citrate | About 16 percent | Good | Reasonable, mildly laxative at higher doses |
| Bisglycinate | About 20 percent | Good | Best of the common forms |
| Malate | About 15 percent | Good | Reasonable |
| Taurate | About 9 percent | Good | Reasonable, a lot of compound per dose |
| Threonate | About 8 percent | Good | Reasonable, and the most expensive |
The forms sold on outcomes
Taurate is marketed for the heart, threonate for the brain, malate for fatigue. None of those has an authorised claim distinguishing it from any other magnesium form.
The claims that exist attach to the mineral, so a taurate product and a bisglycinate product providing the same elemental magnesium carry exactly the same permitted wording. The premium attached to the specialist forms buys the positioning, and taurate and threonate both carry very little magnesium per gram, so reaching a full serving takes a great deal of compound.
Why oxide keeps appearing anyway
It is cheap and it carries the highest percentage of magnesium by weight, so a small amount of compound produces a large elemental figure on a label.
It is also poorly absorbed, and the unabsorbed portion is what produces the laxative effect the form is known for. A high elemental number in a poorly absorbed form is the single most common way a cheap magnesium product looks better than it is.
What matters for someone training
Adherence, which is decided by tolerability. A player taking a serving daily from July through to April will abandon a product that upsets their stomach, and the theoretically superior product left in a cupboard delivers nothing.
Futuro Labs Magnesium Glycinate uses magnesium bisglycinate at 750mg per capsule, a two capsule serving of 1500mg providing 300mg of elemental magnesium at 80 percent NRV, for 22p a day. That is the tolerability argument rather than a claim about superiority.
How to compare any two
Elemental magnesium per serving first, then percentage NRV, then the form, then cost per 100mg of elemental magnesium.
That last figure normalises for the fact that a taurate product needs three times the compound weight of a bisglycinate one for the same magnesium. Futuro Labs Magnesium Glycinate works out at 7.4p per 100mg, and running the same calculation on a specialist form usually produces several times that.
Blends, and why they muddy this further
A growing number of products combine three or four magnesium forms under a single milligram figure, marketed as covering multiple pathways.
No authorised claim distinguishes any form from any other, so combining them cannot produce a benefit that a single form does not. What it does produce is a label where the individual compound weights are often absent, which makes the elemental conversion impossible and means a buyer cannot tell whether the blend is mostly cheap oxide.
Buffered bisglycinate is the same problem in a smaller package: bisglycinate blended with oxide to raise elemental content per gram cheaply, bringing oxide's absorption and tolerability with it. Futuro Labs Magnesium Glycinate uses one form at 750mg per capsule with the elemental figure printed, which is what makes the arithmetic possible at all.
The one question worth asking a label
Does it print the elemental figure. Everything else on this page follows from that single line, because without it no conversion, no percentage NRV, no comparison and no cost per 100mg calculation is possible.
A product that prints the compound weight, the elemental content and the percentage NRV on one panel has made itself checkable. A product that prints only a large compound figure has made a choice, and that choice is more informative about the manufacturer than any form argument. Futuro Labs Magnesium Glycinate prints all three at 22p a day.
Where to go next
- How to compare magnesium forms without the marketingThe full comparison, including format.
- How to work out the elemental magnesium in any supplementThe conversion behind the first column.
- Is magnesium glycinate the right form for rugby players?The form question for a player taking it all season.
The product
Futuro Labs Magnesium Glycinate
Futuro Labs Magnesium Glycinate uses bisglycinate at 300mg elemental per two capsule serving, 80 percent NRV, at 22p a day and 7.4p per 100mg of elemental magnesium. The form is chosen for tolerability rather than for a claim that does not exist.
- 300mg elemental magnesium, 80% NRV
- Bisglycinate, best tolerated common form
- UK made to GMP, lab tested for purity
- Not batch certified for sport
Sharper Rugby is published by Futuro Labs. If you buy through this link Futuro Labs earns from the sale. Prices are set by Amazon.
Questions players ask
Which magnesium is best for sport?
No form carries a sport claim. The claims attach to the mineral at 15 percent NRV or above.
Is taurate better for the heart?
No authorised claim distinguishes it from any other form, and it carries very little magnesium per gram.
Why is oxide so common?
It is cheap and carries a high percentage of magnesium by weight, despite absorbing poorly.
Which form for daily use?
Bisglycinate, on tolerability across a full season.
How do I compare value between forms?
Cost per 100mg of elemental magnesium, which normalises for compound weight.
Does threonate do something different?
No authorised claim says so, and it is the most expensive form per unit of magnesium.