To measure how many calories there are in food, we use a hot little device called a bomb calorimeter.
It burns foods and measures the difference between how much energy went in versus how much energy comes out.
Here’s where it gets confusing if you ever talk to a physicist about your weight loss program: What we call a “calorie” is actually equal to a thousand scientific calories, or a kilocalorie.
So to a scientist, a doughnut doesn’t actually have 235 calories, but 235 kilocalories (235,000 calories). You’d better start jogging.
Which is why the calorie system of weight loss is seriously flawed. Our bodies do not burn food as a bomb calorimeter does & there is a huge amount of energy i.e. calories, which passes straight through & is still capable of being releasing by combustion. Just to reinforce this point, many societies use dung as fuel. Fat, in particular, can pass straight through & very few of its calories enter the body system at all. There’s a lot more propaganda & marketing involved in the slimming industry than truth at times!!