ZMA is a vitamin and mineral supplement used by body builders and other athletes. It contains zinc aspartate, magnesium aspartate and usually vitamin B-6. It is a product by Victor Conte, founder of BALCO Laboratories in Burlingame, California. ZMA was developed for elite athletes who through physical stress and intense training schedules have significant losses of zinc and magnesium.
The studies on ZMA have found no known side effects of the product. A double blind study published in the "Journal of the International Society of Sports Nutrition" in December 2004 monitored 42 trained athletes taking ZMA supplements and found no clinical side effects related to normal supplementation doses of ZMA. The dangers of taking ZMA are in the over-consumption of the supplement leading to excessive accumulation of the minerals in the body.
Nausea and Stomach Upset
Over-consumption of ZMA can cause upset stomach due to high levels of the mineral zinc. Zinc is an essential trace element that is necessary in small amounts for health, according to the National Institutes of Health. Zinc plays a role in immune function and supports normal growth. Too much zinc can cause upset stomach, nausea and vomiting, according to Office of Dietary Supplements. Symptoms of excessive doses of zinc can occur within 30 minutes of ingestion. The normal recommended daily amount of zinc is 40 mg for adults over the age of 19 years of age, according to the ODS. ZMA includes 30 mg of zinc.
Increased Prostate Cancer Risk
Serious side effects are also associated with taking more than the daily-recommended dosage of ZMA. Taking more than 100 mg of zinc daily can increase the risk of prostate cancer; you double your risk of prostate cancer by taking more than 100 mg of zinc daily for 10 or more years, according to the National Institutes of Health.
Prescription Drug Interactions
The zinc in ZMA can reduce the effectiveness of some prescription medications. Zinc can reduce the amount of antibiotic the body absorbs, according to the NIH. If you are taking antibiotics, talk with your health care provider before taking ZMA. Some antibiotics affected include tetracycline, levofloxacin, ciprofloxacin, ofloxacin, moxifloxacin, gatifloxacin, enoxacin, norfloxacin and sparfloxacin.
Water pills, such as Midamor, can increase the amount of zinc in the body. Taking ZMA with water pills can increase the amount of zinc in your to levels that are above normal. If you are taking water pills, talk with your doctor or health care provider before taking ZMA.