I was not sure what I would write today until I saw an advertisement in a magazine I read during breakfast. The ad was for several products from GNC, a so called health and wellness store. One product boasted not only increased calorie burn but rigorous clinical trials to attest to this claim. According to the ad and website, people who take this supplement (and the ingredients are not listed in the magazine or website, so I guess you have to go to the store to read the label) burn more calories before, during and after exercise. [ you know that I diligently searched for the actual research study - nowhere to be found ]
The ad states that it was a double blind randomized placebo controlled study, that of course is what we would hope for, HOWEVER, one test of 25 people does not equal RIGOROUS scientific study. For goodness sakes - yes, we are all so desperate to find these quick and painless cures that we don't apprise ourselves of the small print. The ad also does not say if the difference was statistically significant... and you know why... because it CAN"T be if there were only 25 people.
Supplements can contain any number of fillers and can contain any amount of whatever ingredient the scientists think caused this increase calorie burn. I.e. they are not safe nor guaranteed pure. If you think I am perhaps being too cautious, just remember this.
Obesity and weight loss are BIG BUSINESS, billions of dollars will be made when someone figures out how to give us the metabolism of birds or Olympic runners... if a clinical trial proved something effective, it would NOT be buried in the pages of Real Simple magazine.