What is a calorie?
When talking about a calorie in food, it is a measure of the energy that the food supplies to your body. When talking about burning calories during physical activity, a calorie is a measure of the energy used by your body. To maintain the same body weight, the number of food calories you eat during the day should be about the same as the number of calories your body uses. The number of calories you should eat each day depends on your age, sex, body size, how physically active you are, and other conditions. For instance, a woman between the ages of 31 and 50 who is of normal weight and moderately active should eat about 2,000 calories each day.
A calorie is a unit of measurement for energy. In most fields, it has been replaced by the joule, the SI unit of energy. However, the kilocalorie or calorie remains in common use for the amount of food energy. The calorie was first defined by Professor Nicolas Clément in 1824 as a kilogram-calorie and this definition entered French and English dictionaries between 1842 and 1867. You can find out how many calories are in a food by looking at the nutrition facts label. The label also will describe the components of the food – how many grams of carbohydrate, protein, and fat it contains. Here’s how many calories are in 1 gram of each: carbohydrate – 4 calories protein – 4 calories fat – 9 calories That means if you know how many grams of each one are in a food, you can calculate the total calories. You would multiply the number of grams by the number of calories in a gram of that food component. For example, if a serving of potato chips (about 20 chips) has 10 grams of fat, 90 calories ar
A calorie is a measure of energy expenditure. The calories referred to in diet and exercise, are kilocalories (kcal), 1000 of the calories referred to in science labs for measuring chemical reactions. A pound of fat stores 3500 calories (kcal). To lose half a kilo of fat a week a person must eat approximately 500 fewer calories (kcal) per day than he/she expends. The range of daily calorie burning is from 1600 for a sedentary woman or older people, to 2800 for active men, very active women and teenage boys. You can burn up to 900 to 1400 calories or more in just one 50 minute session. Your body will burn off those calories through the day. The best of all is that the inch loss from infrared is permanent.
This question brings up the topic of how scientists measure energy. Energy can take many forms. One form energy can take is heat. The calorie is a unit used to measure heat. It is defined as the amount of heat needed to raise the temperature of 1 gram of water by 1 degree Celsius. If you want to raise the temperature of 10 grams of water by degree Celsius, it would need 10 calories of energy; to raise the temperature of 10 grams of water by 10 degrees Celsius, would likewise cost you 100 calories. The calorie is often associated with food and dieting. Dietitians have measured the amount of energy that foods contain. If the body performs work (converting some of the stored potential energy into kinetic energy) and uses more energy than it consumes as food, the body will deplete its store of energy. Because a lot of the bodys stored energy is in the form of fat cells, a lifestyle that consumes more energy than it takes in can reduce the amount of fat in ones body.
