ZMA – What Does It Do?

One of the most talked about supplements recently is ZMA . But what exactly is this supplement, and what does it do?

More importantly, does it work?

Here is why I think this is one supplement everyone should try.

One of the most talked about supplements recently is ZMA. But what exactly is this supplement, and what does it do?

More importantly, does it work? Here is why I think this is one supplement everyone should try.

ZMA is a synergistic blend of two minerals, zinc and magnesium, and a vitamin, Vitamin B-6 or pyridoxine.

All three of these compounds

All three of these compounds are extremely important in biological processes, and USDA studies have shown that less than 70% of Americans get enough zinc, and less than 40% get enough magnesium.

It has also been shown that increased exercise can lead to losses of vitamins and minerals.

Zinc is particularly important from a bodybuilding standpoint due to its role in testosterone production.

The old story about oysters being an aphrodisiac is probably related to the fact that they are high in zinc.

Low levels of zinc and magnesium have a strong adverse effect on muscle growth.

So, it’s obvious that people need these minerals and vitamins.

What makes ZMA different is the form of the zinc, and the ratio in which it is combined with magnesium and pyridoxine.

A recent study showed that zinc in the form of zinc monomethionine aspartate combined with magnesium aspartate and Vitamin B-6 (pyridoxine).

When given to training athletes resulted in 43.7% higher testosterone levels and 25% greater IGF-1 levels, as well as a 2.5 times greater strength increase than a placebo group.

What this means is that taking this supplement over a period of eight weeks gave the subjects higher testosterone levels and greater strength increases than the people not taking ZMA.

The Health Benefits of ZMA

Metabolic Muster

Zinc is also critical for maintaining thyroid hormone production. This is important for keeping your metabolic rate (the amount of calories you burn each day) and fat-burning capabilities up.

Being low in zinc can limit thyroid hormone production, and compromised thyroid hormone function results in a lower metabolic rate, which makes it harder to drop body fat.

Research confirms that when your diet is low in zinc, thyroid hormone levels fall and resting metabolic rate drops.

One Study

One study from the University of Massachusetts (Amherst) found that subjects placed on a low-zinc diet had significantly lowered metabolic rates.

When the subjects took 25 mg of zinc each day for 20 days, their metabolic rate jumped up to levels that were higher than even before they followed the low-zinc diet.*

The Selcuk University studies also showed that four weeks of zinc supplementation increased thyroid hormone levels in male wrestlers and sedentary men.

It appears that zinc is not only critical for thyroid function, but also for maintaining levels of the hormone leptin.

This hormone is also important for keeping your metabolic rate high as well as keeping hunger down. Being deficient in zinc has been shown to significantly lower leptin levels.

Support Immunity

It is well established that zinc is critical for immune function. Zinc affects multiple aspects of the immune system.

Research from the Cleveland Clinic suggests that supplementing with zinc helps to support a strong immune system.

Zinc also functions as a powerful antioxidant. This mighty mineral activates an enzyme that may help support overall health and immune function.*

Zinc’s powerful antioxidant properties can enhance not just your health but your post-workout recovery as well. Zinc’s immune-boosting effects can help to keep you healthy and in the gym.


1. While taking a plain zinc and magnesium supplement

While taking a plain zinc and magnesium supplement together may provide you with adequate amounts of these important minerals and cost less than a ZMA supplement, I still suggest you spend the money on ZMA.

The form of zinc and magnesium used in ZMA is a chelate known as zinc monomethionine/aspartate and magnesium aspartate.

This form helps to minimize interference in the absorption of both these minerals.

Furthermore, this form of ZMA provides zinc and magnesium aspartate in the proper dosage, while also serving up the proper amount of vitamin B6, which aids magnesium uptake and utilization by the body.

2. Specific dosages were found to produce positive effects in athletes’ hormone and strength levels.

Men should look for ZMA supplements that provide 30 mg of zinc, 450 mg of magnesium, and 10-11 mg of B6; no more, no less.

Women should take a 20 mg dose of zinc, 300 mg of magnesium, and 6-7 mg B6. Since a full dose of ZMA is usually 3 capsules, the dose for women can be achieved by taking 2 capsules.

Also, be sure that it lists ZMA from SNAC Systems on the label. Anything else is not true ZMA.

3. Be aware that, with zinc, there can be too much of a good thing.

Taking in too much zinc—upwards of 50 mg of absorbed zinc— can lead to negative effects on the immune system and metabolic rate, adversely impact muscle recovery and growth. 

And even reduce levels of HDL (good) cholesterol.

It can also interfere with copper uptake. In other words, the effects will be the opposite of what’s intended in the first place.

4. What about magnesium?

Taking more than 450 mg of it can actually interfere with optimal sleep.

5. One of the most important aspects of supplementing with ZMA is timing.

I have always recommended taking it about 1 hour before bed and 1-2 hours after you eat.

This will not only help to maximize its uptake and utilization, as clinical research confirms, but taking ZMA at this time of day will also enhance sleep quality.

6. Do not take ZMA with any food

It’s critical that you do not take ZMA with any food, particularly food rich in calcium, like dairy.

Both zinc and magnesium are poorly absorbed when taken with food.

Sometimes, it’s a two-way street.

Calcium, for example, interferes with zinc uptake while zinc interferes with the absorption of amino acids.

One way to enhance the uptake of ZMA is to take it with 5 mg of BioPerine, a black pepper extract that’s been found to enhance absorption.

How much ZMA should I take?

Every ZMA supplement comes with its recommended dosage, and it’s best to follow those recommendations.

The original formula contained 10.5 mg of Vitamin B6, 30 mg of zinc, and 450 mg of magnesium.

Each formula will vary, so it’s best to check these numbers before you buy as it should have similar quantities of each ingredient as the original formula.

When to take ZMA

It’s best to take ZMA 30-60 minutes before going to sleep.

You should take it on an empty stomach, as it will help your body absorb the nutrients as you sleep.

Important note: Calcium blocks your body from absorbing zinc, so it’s best to avoid any supplements or foods containing calcium at least a couple of hours before taking ZMA.

To conclude:

  • ZMA has been found effective at boosting testosterone in some cases, but ineffective in others
  • It can boost your strength and enhance performance if taken correctly
  • Take ZMA on an empty stomach 30-60 minutes before bed
  • Avoid consuming calcium or calcium supplements when taking ZMA