Calories, also known as capital letter C, are most commonly used in food labels, which is equivalent to the heat required to raise 1 g water from 14.5 degrees Celsius to 15.5 degrees Celsius at1855 joules,15.5 degrees Celsius. Small card is also called cal, which is common in scientific research literature. 1000 small card equals 1 big card.

Calories, abbreviated as card and cal, are transliterated from English. It is defined as the heat required to raise 1 gram of water to 1 degree Celsius at 1 atmospheric pressure; Calorie is a kind of calorie unit, which is widely used in nutrition measurement and fitness manual. The international standard unit of energy is joule.

Function: heat function: just like computers consume electricity, trucks consume oil, and human daily activities consume heat. Heat not only provides energy for people's exercise, daily work and life, but also provides energy for human life activities. People who lose weight can burn fat through exercise, which can achieve the effect of accelerating calorie consumption and achieve the goal of healthy weight loss.

Calories come from carbohydrates, fats and protein. Generally speaking, adults need at least 1500 kcal of energy every day to maintain body function, because even if you lie still, your body still needs energy to maintain body temperature, cardiopulmonary function and brain operation. Basal metabolic consumption varies with individual height, weight, age and gender.

Human survival needs energy, which is obtained from food. The calorie content in food is a measure of how much potential energy food produces. 1g carbohydrate has 4000 calories, 1g protein has 4000 calories, and 1g fat has 9000 calories. Food is generally composed of these three substances.