Recently a plethora of new products based on the minerals zinc and magnesium have popped up claiming to raise the anabolic hormones testosterone and IGF-1 and possibly improve performance in athletes. The claims are lofty, but are they true? The claims of such products rest on three basic premises.

  • One: athletes are notoriously lacking in zinc and magnesium due to several factors ranging from poor diets to increased usage and excretion of these minerals.
  • Two: zinc and magnesium are particularly important minerals in the production of anabolic (muscle building) hormones needed by athletes.
  • Three: due to competition during digestion, even the inclusion of a multivitamin and other mixed mineral supplements will not correct the deficiency.

That's the basic contention of this zinc and magnesium based product in a nut shell, with some biochemical twists and turns I am leaving out due to space limitations and preserving the brain cells of the readers!

A fourth contention is that these new products are based on a particular form of zinc and magnesium (zinc monomethionine-aspartate and magnesium aspartate)

which are superior to less absorbable forms of the minerals. This brings us to ZMA.

Looking at premise number one, there is a decent body of research that has indeed shown that zinc and magnesium deficiencies are not uncommon in various athletes, such as football players, cyclists, bodybuilders and elite military groups.

Looking at premise number two, it is well established that these two minerals are needed in over 300 different enzymatic reactions and the production of testosterone is one of them. Examining premise number three, there are several studies that examined the issue of nutrient interactions and indeed found that certain minerals compete for absorption and so, may not get absorbed if taken together.

Several studies have found that even the addition of a multi vitamin to the diet of people did not increase the levels of zinc, magnesium and other minerals while the serum vitamin levels did go up. The authors theorized this was due to competition of the minerals in the multi vitamin.

So it would appear that different minerals need to be taken at different times and taking them all together may not be an optimal, or even effective strategy for increasing levels of these minerals in tissues.

The fourth contention regarding the forms of minerals is a bit more unproven in this writer's view. Though it is well known that there is a wide range of absorption between different forms of nutrients, especially minerals, so the concept is not far fetched.

This is the idea behind these new supplements, which is to supply highly absorbable forms of non-competing minerals (in this case zinc and mag) known to be essential for the optimal production of anabolic hormones. Though a variety of companies are now selling this product, the letters ZMA appear in the name or on the bottle if the product is using the patented ingredients.

We note the research done by a Dr. Brilla at Western Washington University. Dr. Brilla found the addition of 30mg of zinc monomethionine-aspartate and 450 mg of magnesium aspartate (the forms used in ZMA) daily to football players had a 32% increase in total testosterone, a 3.6% increase in IGF-1and improvements in strength levels of the group getting the supplement.

So, at this time, the general contention of the companies now selling this new zinc and magnesium based products appears to hold water, though future research needs to further elucidate these findings.

There is however one important caveat one should be aware of with ZMA or any such product. It will only work if there is a deficiency to correct and will not increase levels of anabolic hormones where no deficiency in these minerals exists. ZMA is not magic by any stretch. So, with that warning, I give this supplement a thumb's up, understanding the caveat above.

Telford, R. D., et al. "The effect of 7 to 8 months of vitamin/mineral supplementation on the vitamin and mineral status of athletes," Int. Jour. Sport Nutr. 2 (1992), p. 123-34.

Prasad, A. S. and C. S. Mantzoros, et al. "Zinc status and serum testosterone levels of healthy adults," Nutrition 12/5 (1996), p. 344-8.

Sing, A., et al. "Magnesium, Zinc and Copper status of US Navy SEAL Trainees," Am. Jour. Clin. Nutr. 49 (1989), p. 695-700.

Brilla, L. R. Novel Zinc and Magnesium Formulation (ZMA) Increases Anabolic Hormones and Strength in Athletes Western Washington U., Bellingham, WA and V. Conte, BALCO Laboratories, Burlingame, CA 94010. [at press].

0 0

Post a comment