casual_cyclist wrote:Check out the BBC Horizon documentary, Why are thin people not fat? http://inhumanexperiment.blogspot.com.au/2010/07/why-are-thin-people-not-fat.html
Please don't tell me we're going by yet another TV program, CasualCyclist!
The methodology is appalling.
Perhaps it's because of my background in physical sciences, but these "experiments" violate fundamental principles of controlling variables and even sampling sizes.
Let's take just the first linked article at the end of that blog you refer to.
Sample sizes typically have to be in the hundreds to be meaningful. You don't need many test subjects if the quantity you're trying to measure does not vary very much (all the formulas for determining this involve the standard deviation), but as a proxy quantity, BMR in people can average around 1500 and according to Wikipedia might be as low as 1000 and as high as 2400, so you will need an extremely large number of guinea pigs.
I can imagine that for a drug to be certified by the FDA or to end up on the PBS, it may be that thousands of participants have to be tested before sign-off happens.
But this was sixteen individuals ... sheesh!
All too typical, I'm afraid, of 'studies' promoting this wonder product or method versus that.
Often, self-reporting is the way the evidence is collected, which as Winston has pointed out, can make the whole thing almost worthless.
Now, I understand that that's often the only way a PhD candidate can afford their study, but hey, cheap science can be bad science!
casual_cyclist wrote:The experiment was to take naturally thin people, up their food intake to 5,000 kcal and see what happens ...
That eating more will have anything more than a short term and limited effect on BMR has definitely not been found, not even by the following academic study, which again suffers from a sample size of sixteen. (What is it with these people??? And why do their results, which might usefully act as suggestions for a real study, get publicized? And why do people lap them up reading them?)
The "Do More, Eat Less" is the received wisdom, as the Australian Institute of Sport points out, wisely steering clear of the various prescriptive (and seemingly religious) ways of reducing calories (Atkins vs Veganism vs Paleo, etc).