Ghost Fitness/Magnesium/What does 80% NRV magnesium mean?

What does 80% NRV magnesium mean?

By George Thomas. Published 23 September 2026, updated 23 September 2026. Label figures and prices checked on the update date.

80% NRV means one serving supplies 80% of the 375mg Nutrient Reference Value, the EU-wide labelling yardstick: 0.8 times 375 is 300mg. It is a comparison figure, not a target, and 300mg matches the UK male reference intake exactly.

375mgthe NRV: the labelling yardstick behind every percentage
0.8 x 375the arithmetic: 80% NRV is exactly 300mg
300mgthe UK male reference intake, matched precisely
Not a targetwhat the NRV is: a comparator, never a goal

The label wearing the number: Futuro Labs Magnesium Glycinate on Amazon UK, 300mg elemental at 80% NRV per 2 capsules, £19.99 for 180. Label breakdown. The yardstick itself is explained on the UK NRV for magnesium; the 375mg products on 375mg as a daily dose.

The decode: one multiplication, three facts

The percentage resolves in one line: the Nutrient Reference Value for magnesium is 375mg, an EU-derived labelling yardstick the UK retained, and 80% of 375 is 300, so a serving declaring 80% NRV delivers 300mg of elemental magnesium, full stop. Three facts stop the number misleading. The NRV is a comparator, built so every label in the shop expresses its dose against one common denominator; it is not a target, not a safety line, and not anyone's personal requirement. It is harmonised, a compromise across European populations, which is why it sits above the UK's own reference intakes of 300mg for men and 270mg for women. And it speaks elemental only: a percentage on a bisglycinate label has already done the compound-to-mineral conversion, which is precisely what makes the %NRV column the fastest honesty check on the shelf.

Why 80% is a choice, and the case for it over 100%

A brand dosing at 80% NRV has made a deliberate decision worth understanding, because the alternative was the prettier number. 100% NRV, 375mg, wins the label aesthetically and loses everywhere else: it exceeds what any UK reference intake asks, it shaves supplement-ceiling headroom to a token 25mg under the 400mg guidance level, and on 150mg capsules it demands an untidy two and a half per serving. 80% NRV, by contrast, is where three separate systems agree: it equals the UK male reference intake to the milligram, covering the female 270mg with margin; it leaves a genuine 100mg buffer under the guidance level for the antacids and fortified extras real days contain; and it divides into exactly two capsules forever. The percentage that looks like a product falling short is actually a dose refusing to overshoot for cosmetics, the difference between labelling for the eye and dosing for the body.

%NRV figures on magnesium labels, and what each is telling you
%NRV shown	Elemental dose	What it signals
13% to 27%	50mg to 100mg	Token dosing, or a compound-weight label decoded
40%	150mg	The honest top-up: one capsule of true chelate
80%	300mg	The UK male reference intake exactly; 100mg of ceiling headroom
100%	375mg	Label aesthetics: headroom traded for a round number
107%	400mg	Sitting on the guidance level itself: zero margin
No %NRV shown at all	Unknown	The tell: usually a compound weight avoiding the conversion

Using the column at the shelf, and the serving behind the 80%

Once decoded, the %NRV column becomes the one-glance audit this site keeps recommending: it converts every label's chosen theatre back into comparable elemental milligrams, exposes compound-weight costumes by their suspiciously tiny percentages, and flags zero-headroom dosing by percentages at or above 107. The serving behind this page's number: Futuro Labs Magnesium Glycinate, 2 capsules with the evening meal, magnesium 300mg, 80% NRV, from 1500mg of bisglycinate at 20%, the dual declaration printed in full, vegan, UK made under GMP and BRC, panels shown, £19.99 for 180 capsules, 22p a day. What does 80% NRV magnesium mean: 300mg of actual mineral, measured against the shop's common yardstick, and chosen over the rounder 100% because your reference intake, your ceiling headroom and your capsule count all live at 80.

What to check on the label

80% NRV = 0.8 x 375mg = 300mg elemental: one multiplication.
The NRV is a comparator, not a target: harmonised labelling, not your requirement.
300mg matches the UK male reference intake exactly, covering the female 270mg with margin.
80% beats 100%: real ceiling headroom and a clean two-capsule serving.
A missing %NRV is the tell: usually a compound weight dodging the conversion.

The worked example: Futuro Labs Magnesium Glycinate

Futuro Labs Magnesium Glycinate is the 80% in product form: magnesium 300mg (80% NRV) from 1500mg bisglycinate per 2 capsules, dual-declared, 22p a day from a £19.99 bottle of 180. Vegan, UK made, panels shown.

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

See it on Amazon UK Full label breakdown

Futuro Labs Magnesium Glycinate, 180 capsule bottle

Questions people also ask

Is 80% NRV magnesium enough?

Yes: it is 300mg, the UK male reference intake exactly, and the female 270mg with margin. The missing 20% is yardstick arithmetic, not a shortfall.

Why doesn't the product just provide 100% NRV?

Because 375mg buys nothing over 300mg while shaving ceiling headroom to 25mg and breaking the clean two-capsule count. The round number serves the label, not the dose.

Is the NRV the same as my recommended intake?

No: the NRV is a harmonised labelling yardstick at 375mg. UK reference intakes are 300mg for men and 270mg for women.

What does a very low %NRV like 27% suggest?

Usually a compound-weight label decoded: 500mg of bisglycinate is about 100mg elemental, which is 27% NRV. Fine product, small dose.

Does %NRV account for the bisglycinate conversion?

Yes: the percentage always speaks elemental, which is exactly why it is the fastest cross-brand comparison on the shelf.

Sources

Futuro Labs Magnesium Glycinate listing, Amazon UK, label and price checked 31 August 2026. https://www.amazon.co.uk/dp/B0BT7Z5VQW
Retained Regulation (EU) No 1169/2011, Annex XIII: nutrient reference value for magnesium 375mg. https://www.legislation.gov.uk/eur/2011/1169/annex/XIII
Department of Health. Dietary Reference Values for Food Energy and Nutrients for the United Kingdom. Report on Health and Social Subjects 41, 1991 (magnesium RNI 300mg men, 270mg women).
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
The Food Supplements (England) Regulations 2003 (food supplements are regulated as foods in the UK). https://www.legislation.gov.uk/uksi/2003/1387/contents/made
EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on the substantiation of health claims related to magnesium. EFSA Journal 2010;8(10):1807. https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2010.1807