noun
calorie
Commonly used in contexts of food energy, diet, and exercise. In Japanese, it typically refers to the kilocalorie (kcal) in nutritional contexts, though the same word is used.
このおにぎりは約200カロリーです。
This rice ball is about 200 calories.
毎日カロリーを計算して食事をしている。
I count calories every day when I eat.
キロカロリー explicitly means 'kilocalorie', while カロリー is often used to mean the same in everyday speech.
Loanword from English 'calorie', ultimately from French 'calorie', derived from Latin 'calor' (heat).