Supplement questions are among the more difficult ones dietitians field on a daily basis. There are always questions about whether the supplement is necessary, or even helpful; whether it actually contains the ingredients listed on the label, and whether its effect on an athlete will even remotely resemble the claims made in its magazine ads. Fortunately, though, the vast majority of supplements are essentially harmless in terms of an athlete’s health. They may or may not enhance your performance, but they won’t make you sick or put you danger... except the ones that could do just that.

Unfortunately, I’ve found that with some energy drinks and supplements, athletes often learn best through the mistakes and misfortunes of others.

In consultations and panel-discussions with other sports dietitians in the field, reports of overdosing on stimulant supplements are becoming an increasing concern. It’s through these discussions that I’ve heard horror stories of football players fainting on the field after taking more than the recommended amount of a well known nitric oxide supplement, NO2 Xplode. An autopsy of a Navy officer, who had an outstanding health history up until his unexpected death, indicated his cause of death to be heart failure, possibly related to the hemodialating effects of a similar nitric oxide supplement. In a paper released in May of 2005 in The Journal of Clinical Investigation, Johns Hopkins University and Medical Institutes suggests that the same nitric oxide therapies used to treat heart disease patients can potentially promote heart failure through overgrowth and enlargement of the heart muscle when used inappropriately.

It’s also hard to ignore the increased number of caffeine intoxication cases reported to U.S. poison control centers among children and teenagers who get their hands on energy drinks and supplements packed with caffeine. According to a release by Johns Hopkins University in Newswise Medical News in September of this year, a 2007 survey of 496 college age students, of those consuming energy drinks, 29 percent reported “weekly jolt and crash episodes” and 19 percent reported heart palpitations. It’s important to note, however, that these negative outcomes came from ingesting these products at well above their recommended levels.

It seems that both retail and consumer trends are going for shock-value these days. Manufacturers are adding as much caffeine as possible or mixing and matching as many stimulants together as they can into “one serving” without being held liable if the whole can or package is consumed. Consumers are looking for the most caffeine as possible in a serving, without really knowing what their individual tolerance level is. This is a recipe for disaster.

Spike Shooter, as much for marketing value as for providing a real warning, lists the potential side effects of over-consuming their product right on the label: dizziness, headache, nausea, heart palpitations. Chronic use of nitric oxide supplements is also under fire. Nitric oxide expands coronary arteries, improves blood flow to the working muscles, and helps regulate the strength of heart contractions in those with heart failure, but it can be potentially fatal when consumed in excess by athletes. AAKG (arginine alpha-ketogluterate) found in these supplements, purportedly promotes vasodiolation. Arginine in AAKG is a substrate for the naturally occurring nitric oxide synthase enzyme found in the body. However, increased production of these enzymes, without an increase in other cofactors (also needed in the reaction) does not aid in smooth muscle relaxation in the vasculature (vasodilation), but instead reduces to a different enzyme that contributes to hypertrophy of the heart muscle, or an enlarged heart. This is evidenced in animal studies, as long term effects on humans are unavailable at this time (Journal of Clinical Investigation, May 2, 2005). Of course, the impacts of nitric oxide supplement in humans – both positive and negative - may be obscured by the the mix of caffeine and other stimulants in the products, the creatine, the sodium bicarbonate, or the laundry list of other ingredients contained in one serving.

Back in 2004, the FDA banned ephedra after it became clear that over-consumption of the substance could lead to serious medical problems. Based on the reports, both anecdotal and scientific, coming from the dietitian community in recent months, I will not be surprised at all if more products are removed from the shelves in the coming years. The really unfortunate part is that consumers will be allowed to experiment with potentially dangerous products while researchers and the FDA are still trying to figure out how risky they are.

So, what are you to do? Anyone who has been reading this newsletter for some time won’t be surprised to hear me recommend minimizing supplement usage altogether and sticking to the foundations of a sound and varied nutrition program, perhaps with a multivitamin added in for good measure. But if you’re going to take additional supplements, especially ones that promise to provide dramatically increased energy levels, check the labels for stimulants and use them as directed. With stimulant-laden supplements, there really can be serious consequences for taking too much of a good thing.