UK supplement comparison · Independent
Stop comparing supplements by bottle price.
FairDose compares UK supplements by effective dose, ingredient form, clean-label signals, testing transparency, and cost per usable serving — so you can see what you're actually paying for.
Prices and product details are manually researched and may change. Always check the retailer's current label and price before buying.
| Brand | Elemental | £ / 200mg | Score |
|---|---|---|---|
NaturecanMagnesium Bisglycinate | 200mg | £0.30 | 85 |
ThorneMagnesium Bisglycinate Powder | 200mg | £0.43 | 84 |
NOW FoodsMagnesium Glycinate | 200mg | £0.31 | 84 |
Designs for HealthMagnesium Glycinate Chelate | 200mg | £0.46 | 84 |
Bare BiologyCalm Magnesium | 200mg | £0.47 | 83 |
Preview of the FairDose comparison engine. Ranked by combined value score, not by cheapest bottle.
The FairDose principle
Most comparisons ask the wrong question.
"Which bottle is cheapest?" is the wrong question. Two bottles at the same price can deliver wildly different amounts of magnesium per serving — and wildly different quality.
Effective dose, not bottle weight
We normalise on elemental magnesium per serving — the number that actually reaches you, not the compound weight on the front of the pack.
Form-matched comparisons
Glycinate is compared with glycinate. Forms aren't blended into one league table — they aren't interchangeable on price.
Cost per usable serving
£ per 200mg elemental, not £ per bottle. Bottle-size and serving-size tricks disappear.
Transparency and clean-label signals
Stated dose, third-party testing, no proprietary blends, no avoidable fillers — scored, not assumed.
Magnesium glycinate · FairDose picks
Not ranked by cheapest bottle.
Balanced across cost, transparency and clean-label.
Lowest cost per 200mg, weighted by quality signals.
Highest clean-label score with transparent dosing.
Plain-English guides
Buy magnesium without getting ripped off.
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