Best ZMA supplement


In addition to improving sleep and aiding in muscle growth and recovery, zinc is critical for immune function and acts as a powerful antioxidant.

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Which ZMA supplements are best?

Exercise and nutrition are essential for building muscle and maintaining overall health. But sometimes even that isn’t enough, which is why supplements are so important.

Zinc magnesium aspartate is a combination of zinc, magnesium and vitamin B6. It is often used by athletes and bodybuilders to help build muscle, improve endurance, increase testosterone, and improve sleep. There are a lot of ZMA supplements on the market, but the best is Optimum Nutrition ZMA.

What to know before you buy a ZMA supplement 

Benefits of ZMA

Plenty of supplements are designed to build muscle and aid in recovery, but what makes ZMA unique is the way it helps promote restful sleep. This is the primary reason why many turn to it, and ultimately swear by it, so it can be a good alternative to other sleep support supplements

ZMA is also beneficial because many athletes are deficient in both zinc and magnesium. Zinc can be lost through sweat when training, and foods rich in dairy products can inhibit absorption of both zinc and magnesium. That’s why it’s common not to receive your daily recommended allowance of either through nutrition alone. 


Zinc, magnesium and B6 are the three primary ingredients, but the amount per serving of each varies among brands of ZMA. The typical breakdown is 10.5 milligrams of vitamin B6, 450 milligrams of magnesium and 30 milligrams of zinc. Some brands offer more B6, but zinc and magnesium levels usually remain consistent. In fact, too much magnesium can inhibit sleep. 

Zinc monomethionine and magnesium aspartate are the common forms of these two minerals, but some brands use alternative forms. 

What to look for in a ZMA supplement 

Pill count 

ZMA powder is available, but it primarily comes in bottles of either 90 or 180 pills. The dosage is typically two or three pills, depending on the brand.  

Other formulations 

ZMA is a pretty straightforward supplement, and most brands stick to the three main ingredients, but some add other ingredients to help increase absorption and effectiveness. Some of the most popular include: 

  • Black pepper (bioperine): Enhances the ingredients’ assimilation. 
  • Theanine: Promotes recovery, relaxation and sleep. 
  • Melatonin: Promotes sleep.  


Since calcium can inhibit the absorption of both zinc and magnesium, it’s recommended to not take ZMA with food, and especially not with food containing calcium. 

How much you can expect to spend on a ZMA supplement 

Cost of ZMA supplements can vary depending on the brand and quantity, so check the pill count and serving size when comparing prices. Bottles with 90 pills are typically in the $10-$15 range, while bottles with 180 pills are usually $20-$25. 

ZMA supplement FAQ

When is the best time to take ZMA?

A.  Given that it’s primarily used to help promote sleep, it’s often recommended that ZMA be taken at night, 30 to 60 minutes before bedtime. 

Is dosage the same for men and women?

A. No. Always follow the directions, but many brands recommend men take three pills before bed, and women only take two.

Are there any known side effects of ZMA?

A. No. There is not yet a lot of research on ZMA, and there are side effects of taking excessive amounts of zinc, magnesium and B6, but if you follow the directions on the bottle, it is perfectly safe. However, it’s always best to consult with your physician before taking any supplements to learn of potential reactions with prescribed medication. 

What’s the best ZMA supplement to buy?

Top ZMA supplement 

Optimum Nutrition ZMA

Optimum Nutrition ZMA

What you need to know: This contains the right balance of high-quality forms of zinc, magnesium and vitamin B6 to help fuel an active lifestyle. 

What you’ll love: Intended to fill gaps in your nutrition and micronutrient intake, it also helps convert food into cellular energy and supports immune function. From a trusted brand that has been around for over 30 years, this is available in bottles of 90 and 180 capsules. 

What you should consider: Some customers preferred the company’s old formula to this most recent blend. 

Where to buy: Sold by Amazon and iHerb

Top ZMA supplement for the money

Now Sports Nutrition ZMA

Now Sports Nutrition ZMA

What you need to know: This product has quality ingredients that are quickly absorbed to promote muscle strength and recovery.  

What you’ll love: This contains a higher amount of B6 than similar products to help improve amino acid metabolism and recovery. It doesn’t contain any genetically modified organisms, and it’s steroid-, soy- and dairy-free. It’s GMP quality assured, so the manufacturing process has been closely examined to ensure top quality. 

What you should consider: It’s not vegan friendly. 

Where to buy: Sold by Amazon and iHerb

Worth checking out

Universal Nutrition ZMA Pro

Universal Nutrition ZMA Pro

What you need to know: This helps promote muscle growth and restful sleep, while helping your body absorb more minerals. 

What you’ll love: Geared toward athletes and bodybuilders, this is formulated to boost performance while enhancing natural hormone synthesis. It’s easy for the body to absorb, which can increase the effects. 

What you should consider: It’s best to avoid taking this with dairy, or calcium-containing foods. 

Where to buy: Sold by Amazon


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Ryan Dempsey writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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