Are Sports Drinks Safe and Effective?

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

If you had to name the greatest medical advance over the past two centuries, what would you pick? Smallpox vaccine jumped to my mind, until I realized it was discovered back in the 1700s. The British Medical Journal compiled a list of 15 contenders, but which would take the crown? Would it be anesthesia? Kinda nice to be asleep during surgery. Would it be antibiotics? One of the 15 may be surprising. The medical marvel that was “water with sugar and salt.”

“The discovery that [sugar and salt were absorbed together] in the small intestine…was potentially the most important medical advance [of the] century…[because] [i]t opened the way to oral [re]hydration” therapy—which is to say, simple packets of sugar and salt, in the right ratio, that could be added to water to save the lives of children losing electrolytes through severe diarrhea from diseases like cholera. Here, we’d just hook you up to an IV, give you intravenous rehydration therapy. But cheap, easy oral rehydration has saved millions and millions of children’s lives every year, such that UNICEF can now put out reports like this to help finish the job.

It only costs pennies, though. If only there was a way to sell salty sugar water for two bucks a bottle. Sports drinks are a multi-billion dollar industry fueled by Coke and Pepsi, and even drug companies are now getting in on the action. Researchers went online to see what kind of hydration advice people were getting. Pop quiz! True or false: Fluid consumption during exercise should be based upon thirst. Is that a true or false statement? Fluid consumption during exercise should be based upon thirst. Get a piece of paper, write down your answer. All right, ready? Next question: Electrolyte intake is not generally necessary during exercise. Keeping score? True or false: Dehydration is not generally a cause of exercise-associated muscle cramping. And, last one: Exercise-associated muscle cramping is not generally related to electrolyte loss. And, the answers are: True, true, true, and true. If you said false to any of them, you’re wrong—but in good company. 93% of top websites got the first question wrong, 90% got the second question wrong, 98% got the third question wrong, and they all got the last one wrong. And: “To make matters worse, those websites that would generally be perceived as being [more] trustworthy by the public [like websites of medical or professional organizations] appear[ed] to [do] no better.” So, you shouldn’t feel bad if you got any wrong. No wonder “athletes often have misunderstandings about proper hydration during exercise.”

Doesn’t dehydration hurt performance? Surprisingly, when they looked at triathletes, they didn’t see a correlation between dehydration and marathon-finishing times. In fact, some that lost the most water actually had among the fastest times, as has been noted in other studies.

Your body’s not stupid; it will tell you when you need to drink. “There is now ample evidence” that we can just drink to thirst. And, you do not have to drink your electrolytes. But wait, if you’re sweating and just drink pure water, aren’t you risking washing out too much salt, too much sodium, and ending up with “exercise associated hyponatremia,” too little sodium? That’s caused by drinking too much of anything—”water or sports drinks.” In one of the high-profile cases of a high school athlete who died from it drank two gallons of Gatorade. So, how do we prevent such deaths? Simple, we “drink according to thirst.” So, these “don’t wait until you feel thirsty” statements you hear may actually be doing more harm than good.

We’ve known this since the early 90s, but it “was ignored.” The American College of Sports Medicine instead started telling athletes they should drink ‘as much as tolerable’ during exercise. And, “[w]hat followed was an epidemic of” cases of hyponatremia. “Commercial interests [may have played a role in] “delay[ing] the [acknowledgement] of [these] findings for…decades.”

The current ACSM statement no longer says that—in fact, emphasizing how dangerous it can be to drink too much. But, they still plug sports beverages as sometimes preferable to water. Hmm, I wonder who these authors are? Funding received from the Gatorade Sports Science Institute or on the Gatorade Sports Science Institute Speakers Bureau, Gatorade Science Institute, more Gatorade, a quick step over to the Coca-Cola company, and then back to Gatorade.

So, anyway, which of the 15 medical marvels won? Was it oral rehydration to prevent deaths from cholera? Or, antibiotics to kill off the cholera bugs? No, our greatest medical miracle over the last two centuries was “sanitation”—preventing the cholera from getting into our drinking water in the first place.

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Image credit: Gellinger via Pixabay. Image has been modified.

Motion graphics by Avocado Video.

• antibiotics
• athletes
• beverages
• children
• coconut water
• coconuts
• dehydration
• exercise
• industry influence
• mortality
• muscle soreness
• potassium
• salt
• sports drinks
• sports medicine
• sugar
• water