A calorie is a unit of energy, there are no TYPES of calories.
It is all about insulin production. Excess insulin cases the body to store fat. Excess carbs(sugars) cause insulin spikes and cause the body to store the sugars as fat.
Read Why we get Fat by Gary Taubes.
That's my point.
It's true that a calorie is a calorie- if you're burning energy outside of the human body. Since humans have hormones and the body processes things differently than things happen outside the body, your body doesn't manage calories the way you'd think.
I've done YEARS of research on this, and I used to think the same thing- "a calorie is a calorie", "fat makes you fat", "eat less than you burn to lose weight", etc. But through learning more about insulin resistance, the way the body reacts to sugars (whether complex OR simple carbs), I began to do even more research. It's still not mainstream to believe what I'm saying- but we're getting there.
I went from a high carb/low fat diet (that I followed for about 35 years!) to a high protein/moderate fat/low carb diet and totally transferred my body, my lifestyle, and I eat about twice as much as I used to. I can barely keep the weight on now, even though I didn't cut beer at all. If I cut out the beer, I'd probably weigh 99 pounds!
I do NOT have a fast metabolism naturally, and everyone in my family is overweight. So it's not like I'm naturally thin- I've got my Polish peasant genes that hang onto to weight in normal conditions. I joke that I can outlive just about anybody in a famine, due to my natural tendency to be heavy, particularly around the middle.
I have really come to learn alot about wheat, and due to the "antinutrients" in wheat, I will not eat it unless I have to (like at a dinner party and there is nothing else):
http://www.marksdailyapple.com/why-grains-are-unhealthy/#axzz29a3Y6X8A is a short synopsis of that.
As far as links to what I'm talking about, aside from Gary Taubes (the classic work on this idea), you could look up Chris Kresser's website (link seems down at the moment) and he has posted many studies and research on why the whole calories in/calories out is wrong. Recently, Taubes wrote an article for Newsweek with a synposis of his book (which is over about 600 pages) so this article is shorter and explains the obesity epidemic and why the "calorie is calorie" idea is wrong:
http://www.thedailybeast.com/newswe...p-america-s-obesity-crisis-keeps-failing.html
The thing I said was this though- it is true that if you eat fewer calories then you expend you will lose weight. I totally agree. But my point is that it's not OPTIMUM for health and well being.
Optimum nutrition, which gives you a healthy heart, healthy teeth, healthy body, (which just happens to put me at a slim weight), along with no problems with insulin resistance/metabolic syndrome- THAT is the key for health. That fact that I happen to be at a perfect weight by doing all of that for my health is a bonus, and not the goal.