1 00g of marine fish has 83 calories, and calories, kilocalories, calories and kilojoules are all units of heat. 1 calorie is the amount of heat needed to raise the temperature of 1 g of water by 1 degree after the food we eat is burned, and kilocalories is to make 1 degree.

Calorie (abbreviated as "Calorie" for short) is defined as the heat required to raise 1 gram of water at 1 atmospheric pressure 1 degree Celsius. 1 kcal is equal to 1000 calories, about 4 184 joules. The calories of fat are about 900 kcal per 100 grams; Sugar and protein have only 400 calories per 100 grams.