Optimum Nutrition ZMA Capsules

Optimum Nutrition ZMA Capsules

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  • Combination of zinc, magnesium, and vitamin B6 
  • Claims to increase muscle strength, size, and recovery 
  • High level of quality assurance 
  • 10 mg vitamin B6, 435 mg magnesium, and 28 mg zinc
Manufacturer: Categories: ,

Pros & Cons

What we like ...
  • Effective as a sleep aid for most people
  • Tested for quality assurance
  • May encourage faster recovery
What needs improvement ...
  • Some users experienced laxative effects
  • Some reports of an unpleasant smell

Product Summary

The Optimum Nutrition (ON) ZMA capsules combine high-quality forms zinc, magnesium, and vitamin B6, which is stated to increase muscle strength, size, and to improve recovery. Each serving delivers 10 milligrams of vitamin B6, 435 milligrams of magnesium, and 28 milligrams of zinc. According to ON, the added zinc provides immune support while the magnesium promotes sleep.

ON has a commitment to quality. Each of their products reportedly undergoes independent and in-house testing for cross-contamination and, in addition, all vendors they use must provide a certificate of analysis for the raw material. While the vast majority of reviews were positive, reporting better sleep and recovery, there are a few users who experienced gastrointestinal issues. A select few consumers also reported a foul smell.



Optimum Nutrition

Active ingredients

Vitamin B6, magnesium, and zinc

Servings per container


GGR Community Reviews

Optimum Nutrition ZMA Capsules

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      If you are looking for a ZMA supplement from a company whose commitment to quality is at the forefront, ON’s ZMA capsules may be for you.