https://en.wikipedia.org/wiki/Atwater_system https://en.wikipedia.org/wiki/Atwater_system protein is counted as 4 because it's harder to digest, even though it

https://en.wikipedia.org/wiki/Atwater_system https://en.wikipedia.org/wiki/Atwater_system protein is counted as 4 because it's harder to digest, even though it's more than 5 calories when burned carbs and fats are easy to digest so they're counted as-is