Ghost Fitness/Magnesium/How much ZMA dosage per day should you take?
How much ZMA dosage per day should you take?
The short answer
The classic ZMA dose is 30mg zinc, 450mg magnesium and 10.5mg B6, and it fails the audit on two lines: zinc exceeds the 25mg guidance level and magnesium sits at or over the 400mg supplemental level. The dose that survives is 10 to 15mg zinc and 300mg magnesium, from separate tubs.
- The classic dose30mg zinc, 450mg magnesium as aspartate, 10.5mg B6; a smaller dose sold for women
- Line one: zinc30mg against the 25mg UK guidance level: over
- Line two: magnesium450mg against the 400mg supplemental guidance level: at or over
- The dose that survives10 to 15mg zinc by audit, 300mg elemental magnesium, no B6 needed
Our brand: the worked example on this page
Futuro Labs Magnesium Glycinate
- 22p a day
- 180 capsules, 2 capsules daily
- Lab tested
- Made in the UK
The magnesium line, dosed under the level: Futuro Labs Magnesium Glycinate on Amazon UK, 300mg elemental at 80% NRV, under 400mg, in the better-tolerated salt, £19.99 for 90 days at 22p. Full label breakdown. The ZMA-worth verdict is on the ZMA-worth page; the double-counting sums on the ZMA-plus-glycinate page.
The classic formula, and the audit that reads each line against the UK guidance
How much ZMA per day is answered by the formula the products copy and then by an audit the products do not run, line by line against the UK guidance levels. The classic formula, from the original trial and printed on most ZMA labels since: per full daily dose, 30mg of zinc, as zinc monomethionine and aspartate or a similar salt, 450mg of magnesium as magnesium aspartate, declared as elemental on the labels that follow the formula, and 10.5mg of vitamin B6 as pyridoxine, usually three capsules for men taken at bedtime on an empty stomach by the marketing's instruction, with a two-capsule dose sold for women delivering two thirds of each. Line one, zinc: the UK expert group's guidance level for supplemental zinc is 25mg a day, above which sustained intake is not advised, the copper-depletion effect being the reason, and 30mg exceeds it on the tub alone, before any multivitamin, lozenge or fortified food is counted, so the men's dose fails the zinc line and the women's 20mg passes it only if nothing else contributes. Line two, magnesium: the supplemental guidance level for magnesium is about 400mg a day, the laxative effect being the practical ceiling, and 450mg sits at or over it, as a less well-tolerated salt, aspartate, so the men's dose fails the magnesium line too and the women's 300mg passes. Line three, B6: 10.5mg sits at the UK expert group's guidance level of 10mg for long-term supplemental vitamin B6, lawful and at the edge of its own line, and it is a large dose of a vitamin most training diets supply, unnecessary rather than unsafe. The audit's result is that the classic men's ZMA dose fails two of its three lines against UK guidance, which is a finding about the formula and not about any brand, and which the empty-stomach bedtime instruction compounds by putting 30mg of zinc into a fasted stomach, the nausea the with-food pages describe.
The evidence behind the dose, the dose that survives the audit, and the honest replacement
The evidence behind the classic dose is the reason it has never been revised: the original ZMA trial, in college footballers, reported gains in strength and hormones and was linked to the formula's developer, and the one independent replication, in trained men over eight weeks, found no effect on strength, body composition or anabolic and catabolic hormones, the ZMA-worth page's verdict that for most lifters the formula is not worth its premium, so the dose was set by a trial that did not replicate and has stayed there by inertia. The dose that survives the audit is the one the zinc-and-magnesium pages reach from every direction: zinc at 10 to 15mg a day where a diet audit finds intake short, under the 25mg level summed across every tub and carrying zinc's lawful claims, testosterone maintenance, immune function, fertility, at adequacy; magnesium at 300mg elemental as bisglycinate, under the 400mg level in the better-tolerated salt, for its own claims, muscle function, nervous system, psychological function, fatigue; and no B6 beyond a diet or a multivitamin. Taken with the evening meal rather than fasted at bedtime, from two stated tubs rather than one formula, and dosed for men and women alike by audit rather than by capsule count. The honest replacement for a ZMA habit is therefore not a smaller ZMA dose, though a woman's two-capsule dose passes both lines, but the two-tub version of what ZMA was trying to be, the worked example being the magnesium half at 300mg elemental and 22p and a small zinc tablet the other half if the audit says so, the formula's useful part kept and its two failed lines corrected.
| The line | The classic men's dose | The UK guidance and the verdict |
|---|---|---|
| Zinc | 30mg | 25mg supplemental: over |
| Magnesium | 450mg as aspartate | About 400mg supplemental: at or over, in a poorer salt |
| Vitamin B6 | 10.5mg | At the 10mg long-term guidance level; unnecessary |
| The timing | Fasted at bedtime | Zinc fasted causes nausea: with the evening meal |
| The evidence | One linked trial; the independent replication null | Not worth the premium for most |
| The dose that survivesOurs | 10 to 15mg zinc by audit; 300mg elemental magnesium; no B6 | Two stated tubs, under both levels |
The verdict, a formula that fails two lines and a dose that passes
How much ZMA per day should you take: the classic formula's 30mg zinc, 450mg magnesium and 10.5mg B6 fails an audit against UK guidance on two lines, zinc over the 25mg level and magnesium at or over the 400mg level in a less well-tolerated salt, with its fasted bedtime instruction adding nausea and its evidence resting on a linked trial the independent replication did not confirm, so the dose that survives is 10 to 15mg zinc by audit and 300mg elemental magnesium from separate tubs at the evening meal, no B6 needed. The magnesium line, under the level: Futuro Labs Magnesium Glycinate, 300mg elemental at 80% NRV, bisglycinate, £19.99 for 90 days at 22p a day.
What to check on the label
- Know the classic formula: 30mg zinc, 450mg magnesium, 10.5mg B6.
- Audit the zinc: 30mg is over the 25mg level.
- Audit the magnesium: 450mg is at or over 400mg, as aspartate.
- Take it with the evening meal: never fasted at bedtime.
- Replace it with two tubs: 10 to 15mg zinc by audit, 300mg magnesium.
Our brand
The worked example: Futuro Labs Magnesium Glycinate
Futuro Labs Magnesium Glycinate is the worked example for magnesium reviews because its label states every number a review needs: 1500mg magnesium bisglycinate at 20%, 300mg elemental, 80% NRV, 2 capsules a day, 180 capsules for £19.99, 22p a day, UK made, vegan HPMC shell, batch tested for lead, mercury, arsenic and cadmium, and only the register's own magnesium claims printed.
- Elemental magnesium per serving
- 300mg (80% NRV)
- Form
- magnesium bisglycinate 20%
- Serving
- 2 capsules a day
- Bottle
- 180 capsules, 90 days
- Price
- £19.99 (22p a day)
- Capsule
- vegetarian shell, vegan product
Questions people also ask
What is the standard ZMA dose?
The classic formula per full daily dose is 30mg zinc, 450mg magnesium as aspartate and 10.5mg vitamin B6, usually three capsules for men and two for women, taken by the marketing's instruction fasted at bedtime.
Is the ZMA dose safe by UK guidance?
The men's dose fails two lines: 30mg zinc exceeds the UK supplemental guidance level of 25mg, and 450mg magnesium sits at or over the 400mg supplemental level in a less well-tolerated salt, while the women's two-capsule dose passes both if nothing else contributes.
Should ZMA be taken on an empty stomach?
No: the fasted bedtime instruction is marketing with no absorption evidence, and 30mg of zinc in an empty stomach causes nausea in many people, so any zinc-and-magnesium habit belongs with the evening meal.
Does ZMA work?
The original trial, linked to the formula's developer, reported gains; the one independent replication in trained men found no effect on strength, body composition or hormones, so for most lifters the formula is not worth its premium.
What should I take instead of ZMA?
Two stated tubs dosed by audit: magnesium bisglycinate at 300mg elemental with the evening meal, and a separate 10 to 15mg zinc where diet runs short, under 25mg across every tub, with no B6 beyond a diet or multivitamin.
Sources
- Expert Group on Vitamins and Minerals. Safe Upper Levels for Vitamins and Minerals. Food Standards Agency, 2003 (magnesium guidance level 400mg a day from supplements). https://cot.food.gov.uk/sites/default/files/vitmin2003.pdf
- Wilborn CD, et al. Effects of zinc magnesium aspartate (ZMA) supplementation on training adaptations and markers of anabolism and catabolism. Journal of the International Society of Sports Nutrition 2004;1(2):12-20. PubMed record
- Brilla LR, Conte V. Effects of a novel zinc-magnesium formulation on hormones and strength. Journal of Exercise Physiology Online 2000;3(4):26-36.
- The GB claims register, zinc entries: zinc contributes to the maintenance of normal testosterone levels in the blood, to normal fertility and reproduction, to normal immune function and to the maintenance of normal skin, hair and nails, among others, at 15% NRV or more. https://www.gov.uk/government/publications/great-britain-nutrition-and-health-claims-nhc-register