Hormone-related claims evidence brief
ZMA combines zinc, magnesium, and vitamin B6. It is commonly promoted for testosterone, sleep, recovery, and deficiency support, but the formula is not magic if intake is already adequate.
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.
8-week RCT: no hormone-marker, body-composition, or strength advantage.
Evaluate zinc and magnesium status separately. A branded ZMA stack is not automatically better than correcting a documented deficiency.
Sleep and hormone marketing are not supported; high-dose zinc can create copper issues and magnesium form affects tolerability.
Source Drawer
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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