Do humans burn alcohol for calories and are there other things besides carbohydrates, fat, and protein we get calories from?

Question

I’ve always heard that calories are just from carbohydrates, fat, and protein. But I heard recently we get calories from alcohol. And that alcohol is not just a form of one of the other 3. We get a different amount of calories from alcohol than any of the other 3.

* Fat: 1 gram = 9 calories
* Protein: 1 gram = 4 calories
* Carbohydrates: 1 gram = 4 calories
* Alcohol: 1 gram = 7 calories

So do we get calories from alcohol as a separate type of substance than the other 3? And are there other things we can/do get calories from that are not normally listed?

In: Biology

Answer 1

There are other things we can digest for energy (some sugar alcohols and organic acids) but we typically consume them in far fewer amounts than any of the other 4.