[pvnick]

Your statement is only marginally correct, but mostly misleading to the point of being practically wrong. Depending on what you eat, your body absorbs 80%-97% of calories according to the following (simplified) equation:

Energy in = Energy out + Change in Body Stores [1]

Where "change in body stores" is, for all intents and purposes, either muscle or fat. So while going from eating 3000 calories of pure butter to eating 3000 calories of straight fibrous vegetables will show a modest difference in caloric retention, I guarantee you that's not the case here.

[1] http://www.bodyrecomposition.com/fat-loss/the-energy-balance...

[philwelch]

The point is, don't gloss over things by making dumb statements like "it's impossible because of the laws of thermodynamics". The laws of thermodynamics don't preclude engines that either leak fuel or are fantastically inefficient in converting them to any particular form whether it be locomotion, electricity, or adipose tissue. If your point is that the human body is fantastically efficient at producing fat in ways that don't really vary, then prove that point.

[pvnick]

Please don't insult me like that without at least reading the article I posted, which directly supports the statement "it's impossible because of the laws of thermodynamics"

[philwelch]

I'm not insulting you. The law of conservation of energy is insufficient to support your claim because your claim relies more on the particulars of human physiology than on the basic physics. If it were all down to physics, then my car would get fat when I put fuel in the gas tank and didn't drive it. But even though my car and my body are both governed by the same laws of physics, the details are different.