Verified Supplement Data Primary-sourced
01 / Evidence-based supplement data

The price that matters is per clinical dose.

We compare supplements by the cost to take the amount actually studied in trials — every claim linked to its source, every label checked against the NIH database, no paid placement.

Strong evidence Moderate Limited we grade every claim, and say so plainly
Magnesium · cost / clinical doseLIVE
Glycinate 400mg
USP · high absorption
$0.24
Citrate 200mg
moderate absorption
$0.31
Oxide 250mg
~4% absorbed
$0.92*
BEST $0.24WORST $0.92
* per absorbed mg — the "cheap" pill costs the most. Source: PMID 11794633
Sourcing
Every claim → a PMID
Products
Checked vs NIH DSLD
Ranking
Cost / clinical dose
Independence
No paid placement

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Medical disclaimer: Educational health information based on published clinical research — not medical advice, and not a replacement for your physician. Always discuss supplement changes with your doctor, especially if you take medications or have a health condition. Methodology.

Affiliate disclosure: As an Amazon Associate I earn from qualifying purchases. Rankings are determined by cost per effective dose and clinical evidence, not affiliate commissions. Read our methodology.