Please consider this my Olympics curtain-raiser (journalese for a story that previews a coming event): As you watch the games, which open next Friday, you'll likely see a great many ads that use gorgeous gleaming musculature to promote sports-related products from "power drinks" to sneakers. So here's an advance prescription for several grains of salt, to be taken daily.
BMJ, formerly known as the British Medical Journal, and the BBC report that there's a "striking lack of evidence to back up claims for popular sports brands" — claims that drinks or sneakers can improve performance or enhance recovery.
They conclude that it is “virtually impossible for the public to make informed choices about the benefits and harms of advertised sports products.”
The BMJ carries a fascinating article on "The Truth About Sports Drinks" here. It's the story of how a little recipe of water, sodium, sugar, and monopotassium phosphate with a dash of lemon flavoring, concocted in the sixties, has turned into a major industry — even though the science behind it is underwhelming.
[module align="right" width="half" type="pull-quote"]Drink when you're thirsty.[/module]
I contacted my favorite reality-checker on anything food-related, the Center for Science in the Public Interest, and what senior nutritionist David Schardt told me about sports drinks made them lose their magic for me forever:
"These are really just like soft drinks. They’re basically empty calories, because most people exercising don’t need what’s in these drinks. Water is a perfectly good fluid for quenching your thirst. And some of the research on these products showing a benefit apply only to people undergoing extraordinary exertion, and not your normal soccer-playing child or jogging adult. So people should think of these as soft drinks, as soda. But they've gotten this reputation as being something special, so when school districts, for example, banish soda, they often make an exception for sports drinks, and that's just not based on the facts."
Ugh. Now what am I going to do with all that Gatorade powder I bought? At least, David Schardt said, it's not that sports drinks are harmful; they're just unnecessary calories.
From the press release:
The investigation also explores the role of sports drinks companies in the “science of hydration” and questions their links with some of the world’s most influential sports bodies in a bid to gain public trust in their products and persuade ordinary people they need more than water when they exercise.
But Arthur Siegel, Associate Professor of Medicine at Harvard University, says we are being misled about the dangers of dehydration and industry advice to “stay ahead of thirst” when, in fact, drinking too much of any liquid can be fatal.
A team at Oxford University tested the evidence behind 431 performance-enhancing claims in adverts for 104 different sports products including sports drinks, protein shakes and trainers.
If the evidence wasn’t clear from the ads, they contacted the companies for more information. Some, like Puma, did not provide any evidence, while others like GlaxoSmithKline – makers of Lucozade Sport – provided 174 studies.
Yet only three (2.7%) of the studies the team was able to assess were judged to be of high quality and at low risk of bias. They say this absence of high-quality evidence is “worrying” and call for better research in this area to help inform decisions.
Many top sports scientists support this view. Professor Tim Noakes from the University of Cape Town says that while sports drinks may be helpful for elite athletes, the drinks companies rarely study ordinary gym goers. Many also contain high levels of sugar.
Yet sports drinks like Lucozade, made by GlaxoSmithKline, and Powerade, made by Coca Cola - the official drink of the 2012 Olympics - are sold in supermarkets and will soon have the European stamp of approval that they “help maintain endurance performance.”
Dr Matthew Thompson from the Oxford team is also concerned about rising levels of obesity among children and young people. He says anything that suggests sports drinks are good for us “could completely counteract exercising more, playing football more, going to the gym more.”
This program aired on July 20, 2012. The audio for this program is not available.