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2/5 Weak evidence

Testosterone booster evidence brief

ZMA

Zinc, magnesium, and B6 can matter when intake is low, but ZMA formulas do not have strong evidence for raising testosterone or improving strength in replete lifters.

Deficiency stack, weak anabolic case strength / recovery / health 5 linked sources Content audit 2026-05-04

Headline Finding

8-week RCT: no anabolic-hormone, body-composition, or strength advantage.

Dose Context

Evaluate zinc and magnesium status separately. A branded ZMA stack is not automatically better than correcting a documented deficiency.

Important Caveat

Anabolic sleep and testosterone-booster claims are not supported; high-dose zinc can create copper issues and magnesium form affects tolerability.

Source Drawer

Linked Research

5 papers and evidence links - audit 2026-05-04
  1. Trial ZMA resistance-training RCT
  2. Trial ZMA trial PDF
  3. Systematic review Testosterone boosters systematic review
  4. Systematic review Mineral performance systematic review
  5. Review Iron, zinc and magnesium review

How To Read This Rating

The score reflects evidence that the supplement does its stated job. Some jobs are direct, such as strength, endurance, or recovery; others are indirect, such as sleep, mood, appetite, or health support. A real effect can still receive a cautious practical rating when dose, safety, product quality, or audience fit remain uncertain.

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