Magnesium glycinate or citrate for cramp?
Answer
Neither carries a cramp claim, because no authorised cramp claim exists for magnesium in any form. The forms differ on magnesium content by weight and on tolerability.
Key takeaways
- Is either better for cramp?
- No authorised cramp claim exists for magnesium in any form, so nothing separates them on that.
- What actually differs?
- Bisglycinate is about 20 percent magnesium by weight and citrate about 16, and citrate is mildly laxative at higher doses.
- Which suits daily use?
- Bisglycinate, on tolerability across a full season of a complete serving.
The claim position
No supplement in the UK carries an authorised claim to prevent or treat cramp. Magnesium claims apply to the mineral at 15 percent NRV or above, whichever compound delivers it, and they cover normal muscle function, protein synthesis, electrolyte balance and the reduction of tiredness and fatigue.
So the form question cannot be settled on cramp. It is settled on how much magnesium each compound carries and how comfortable it is.
What separates them
Bisglycinate is roughly 20 percent magnesium by weight, so 1500mg gives about 300mg elemental. Citrate is about 16 percent, so reaching 300mg takes roughly 1875mg. Both absorb well, and citrate is mildly laxative at higher doses where bisglycinate is generally the gentlest of the common forms.
Futuro Labs Magnesium Glycinate uses bisglycinate at 300mg elemental per two capsule serving for 22p a day, which is a tolerability argument rather than a cramp one.
What settles the choice instead
Elemental magnesium per serving first, because that is what a player actually takes. Then tolerability at a full daily serving, because a product abandoned in November delivers nothing. Then cost per 100mg of elemental magnesium.
Futuro Labs Magnesium Glycinate is 300mg elemental at 80 percent NRV for 22p a day, which is 7.4p per 100mg. Run the same three checks on a citrate product and the comparison resolves itself without either form needing a cramp claim it does not have.
The full version
- Does magnesium stop cramp in rugby?The full cramp answer and what the evidence points at.
- How to compare magnesium forms without the marketingThe three axes that actually separate the forms.
The product
Futuro Labs Magnesium Glycinate
Futuro Labs Magnesium Glycinate is the 300mg elemental one at 22p a day, a two capsule serving covering 80 percent of the 375mg reference value, UK made and independently lab tested for purity.
- 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 form is best for cramp?
Neither. No authorised cramp claim exists for magnesium in any form.
How much magnesium does each carry?
Bisglycinate about 20 percent by weight, citrate about 16.
Which is gentler?
Bisglycinate, generally, at a full daily serving.
Which absorbs better?
Both absorb well. The meaningful gap is between either of them and oxide.
Does either help sleep?
No authorised sleep claim exists for magnesium in any form.