GNC's "tri-pepper blast" diet pills burn as many calories as a 20 minutes walk. Except the study "proving" this was funded by GNC itself. So what's the real story behind these numbers? Should you buy these pills to lose weight?
General Nutrition Centers (GNC) contacted the University of Oklahoma Health and Exercise Science Department to test the weight loss potential of a new supplement they're producing, called Tri-Pepper Blend. The University of Oklahoma has been creating a close relationship with nutritional supplement industry in order to increase their otherwise limited funding.
The results of the study have been published in the peer-reviewed Journal of Strength and Conditioning Research, and seem to have been undertaken with sufficient scientific rigor. The paper shows that taking the supplement increases energy expenditure, heart rate, and oxygen consumption, which has been interpreted to the equivalence of a 20 minute walk.
The methodology of the paper seems fairly solid. It was a double-blind placebo-controlled crossover trial, performed on 28 healthy twenty-somethings. Across the board the spice pills seemed to increase the signatures of using energy.
Given the solidity of the data, and the fact that this made it into a peer-reviewed journal, their conclusions seem reasonable, even if they are funded by a company that profits from this result. However, the 20 minute walk comparison is where things start to get a bit curious.
A 20 minute walk actually doesn't do very much, if you're in vaguely decent shape. Walking for a third of an hour will only burn around 100 calories, depending on your weight and speed. Which, unfortunately, isn't a whole bunch. How much is it? Have a look at this website, which breaks down what 200 calories is, by different food products. Now halve that.
The other interesting thing to look at, is what's in the pill itself. According to the study, it has 200mg of caffeine, 0.67mg of 100,000 scoville capsaicin, 20mg of niacin, and 5mg of bio perine. 200mg of caffeine is a substantial dose; it's more than a 16oz energy drink, around 2.5 espressos, and the same as a tablet of NoDoz. It's around 2/3 of your recommended caffeine intake for the day. Not exactly a pill you want to be popping every hour on the hour in order to lose some weight.
The research paper also comes to a significantly different conclusion than the press release that accompanied it. The press release says that the supplement "has the potential burn as many calories as a 20-minute walk". However, the paper itself doesn't mention calories or 20 minute walks, but instead focuses on how the supplement — when combined with exercise — seems to boost energy consumption. The scientists write, "Thus, it is possible that the thermogenic supplement used in the current study may aid in weight management when combined with long duration (60 minutes) low intensity (walking) exercise." Hardly the same as saying a pill is equivalent to a 20 minute walk.
So what does this mean? Research papers regularly go through a "sexifying" process with an accompanying press release, in order to drum up interest. If possible, it's worth digging through the PR speak to see what's actually being discussed, and what the numbers mean — especially if a corporation directly benefits from the results.