Do the calories in Bacon include the left-over grease?

madeleinedacey15

I think it must be the case that some do and some don't because some of the bacon nutrition labels I read say 100 calories/slice and others give half that.

What you can do is take into account the fact that 1 gram of pure fat contains 9 calories.

If you assume bacon is pure fat (which is conservative, because it contains protein and water as well at 4 and 0 calories per gram respectively), then it will not have more than 9 calories per gram.

So if you have a 5 gram slice of bacon, it likely contains ~45 calories.