The estimable British Medical Journal has just published a provocative expose on the “sports drink” industry. You know the stuff: Powerade, Gatorade, etc. As you’re watching the Olympics, no doubt you’ve caught some screen shots of competitors drinking them and have seen their ads.
The theory behind these products is deceptively simple: Dehydration leads to decreased athletic performance. Salts are lost along with water during exercise. Exercise requires caloric expenditure. Voila! Along come products with a perfect balance of water, salt, and carbohydrate. The products come with an impressive resume of “clinical trials” attesting to their benefit, and are endorsed by a number of athletic organizations.
At first, I wasn’t sure that this expose would be of interest to the wilderness traveller. As a little experiment, however, I checked out “sports drinks” and “electrolyte drinks” on a few of my favorite on-line retailers of backpacking gear: Campmor, EMS, and REI. All offer a wide variety of powdered and tablet forms of these for the camper. EMS, for example, features “GU Electrolyte Brew”. The EMS website claims that the product will “get your system back in balance” and “help you go longer”. Hum…
I urge you to read this report yourself. It is in the July 18, 2012 issue of the BMJ, which should be available in many university libraries. Online access is available at:
The quick summary of the report is not pretty. The real science behind these drinks is almost completely lacking. Company claims to the contrary, when the medical journal attempted to review these studies it found virtually none of sufficient methodologic rigor to withstand scrutiny. The few which had been published in journals were overwhelmingly published in very low-impact journals with clear ties to the sports drink industry. For example, the journal Medicine and Science in Sports and Exercise is published by an organization with long-standing financial relationships to Gatorade, and has a number of “Gatorade affiliated scientists” on its editorial board.
The promoters of these products have largely “invented” dehydration as a common problem in endurance exercise, and have encouraged the promulgation of completely unsubstantiated recommendations for overhydration during sports. Unfortunately, these are filtering down to youth sports.
Is there a problem with all this? There is.
First of all, sports drinks contain calories–hundreds per serving. This may not be a problem for truly active folks, but the average person drinking Gatorade isn’t Usein Bolt! By marketing an image of health and vigorous exercise, companies fool the average (mostly sedentary) user into thinking that he is drinking something other than, essentially, sugar water with a dash of salt.
More importantly, however, the widespread emphasis on sports hydration over the past few years is likely fueling a real problem: hyponatremia. This condition, which is basically a fancy name for water intoxication, is a serious cause of death and disability in some endurance sports. There are at least 16 recorded deaths and over a thousand critical illnesses in marathon running alone attributable to hyponatremia. Although sports drink makers insist that the salt content of their beverages avoids this complication, this is not correct. Indeed, an actual scientific study of marathon runners has shown that the volume of liquid consumed, independent of its composition, is the major factor in causing hyponatremia.
Millions of years of evolution have led to our bodies having an excellent mechanism for preventing dehydration. The mechanism is “thirst”. Pay attention to it. When it calls, have a drink. Of water. Right from the stream!