Which form should you actually buy?
Side-by-side comparisons of supplement forms, doses and timing. Every number is traced to its original study, and where the evidence runs out, we say so.
Start with a comparison
The question most people are actually asking at the shelf.
Magnesium Glycinate vs Magnesium Oxide
Magnesium oxide carries 4x more elemental magnesium per mg, but the only head-to-head trial found no absorption difference. What labels don't tell you.
More comparisons in progress
Magnesium glycinate vs citrate, vitamin D2 vs D3, folate vs folic acid, ubiquinol vs ubiquinone.
What makes this different
Numbers that survive checking
The absorption figures repeated across supplement sites mostly trace back to studies that measured something else, or to nothing at all. We check before we publish.
Evidence has a grade
Every claim is marked Strong, Limited or None. A supplement with no controlled trials is labelled that way instead of being described in confident language.
Label maths you can use
A 500 mg capsule is 500 mg of a compound, not of the mineral. We show the conversion so you can compare two bottles honestly.
SupplementHub is an information resource, not a medical service. Nothing here is a diagnosis, a treatment plan, or a recommendation to take any product. Speak to a doctor or pharmacist before starting a supplement.