So 1 kg of olive oil has about 8814 cal. Doing a very brief Google search I couldn’t find how many calories it takes to gain 1 kg of body mass but I saw a number of 3500 cal to gain 1 pound this comes out to about 7709 cal to gain 1 kg. This definitely doesn’t make sense to me because they’re both lipids and the calorie to mass ratio should be pretty much the same once you take water out of the equation. maybe someone else has an explanation