Calories are units of energy. Just as watts are used to measure electric energy, calories are used to measure thermal energy.

1 calorie (cal) is the energy required to raise 1 gram of water by 1 degree. Food energy is usually calculated in kilocalories, also known as calories (1Kcal= 1000cal).

In the international unit, energy should be expressed in joules. 1 calorie =4. 182 joules, then 1 kcal =4. 182 kj. This unit is sometimes used to represent the energy in food. Many times, people still use kilocalories to calculate the energy in food, because it is more convenient. 1 g starch or sugar contains 4 kilocalories; 1g fat contains 9 kcal, 1g protein contains 4 kcal. For example, if you eat 10 grams of fat, it will bring 90 kilocalories to your body. If you eat 50 grams of popcorn, you will increase the energy supply by about 170 kcal. The energy a person needs every day is also calculated in kilocalories. If you eat a medium-sized apple (about 90 kcal) every day without doing too much exercise, you will gain 10g of fat every day, which is equivalent to gaining 3.6kg of weight every year.

metabolism

Metabolism includes three main parts:

Resting metabolic rate;

Energy consumed by physical activity;

The energy consumed by digesting and absorbing food.

Rest metabolism is the energy used to maintain the operation of body tissues every day; It is the heat energy consumed by the brain, heart, kidneys and all organs and cells of the human body. Rest metabolism accounts for 2/3 to 3/4 of our daily energy consumption.

The second component of metabolism is the energy consumed by physical activities, such as walking, climbing stairs, holding children and planned physical exercise. The heat energy consumed by physical activity is the most diverse part of metabolism, and people have the greatest control over it.

Finally, the energy consumed by digesting and absorbing food is relatively small, about 10%.

Thermodynamic law

The only scientifically proven way to lose weight is to consume more energy than intake. This is the so-called "law of thermodynamics", which has been confirmed again and again by strict scientific research in the past decades. One of the hundreds of studies was conducted in Switzerland. The daily energy intake of 54 obese people was strictly controlled within 1 100 calories, and the combination test of different foods and meals was carried out. There is no difference in losing weight; The weight loss of participants can be attributed to the energy consumed, not the way to provide energy.

Finally, the only way to lose weight is to consume less energy and/or more energy from food. However, only 1/3 people who are losing weight are trying this recommended method of losing weight-eating less and exercising more, which is the root of losing weight.

Mint fitness expert group