What are calories? The energy received from foods is measured in calories. Carbohydrate, fat, and protein are the main sources of energy. As a matter of fact a calorie is a measure of heat energy. The energy in food may be quantified by determining the production of heat as a result of burning the food. Physiological values for 1 gram of carbohydrate or protein are 4 calories. One gram of fat produces 9 calories. Food energy is stored as liver glycogen and fat of the body.
What are calories from foods?
The body uses the calories from foods for muscular work, producing enzymes and hormones, building structural constituents and performing numerous functions. The body activity is inseparable from the production of warmth. Heat is produced to maintain body temperature at the level, which is necessary for normal functioning. Foods provide essential constituents for cells and tissues. Foods supply energy for vital chemical reactions. The energy concentrated in foods is determined by the amounts of energy contained in carbohydrate, fat, and protein. Food energy is usually represented in a mixed form. However, sugar and oil are sources of pure carbohydrate and fat energy.
What are calories and existence?
In rich countries 15 % of energy is taken from protein, 35 % of energy is from fat, and 50 % of energy is of carbohydrate origin. On the other hand, in poorer countries, the cereals prevail in the diet and carbohydrate covers a larger part of energy demands; protein and fat give smaller share of energy.
What are calories and energy distribution?
Energy is consumed in physically active conditions and even in motionless state. Considerable part of the energy supports basic metabolism. Such functions as maintenance of body temperature, respiration, heart activity, numerous physiological functions and biosynthesis necessitate considerable amounts of energy. Even digestion and the subsequent food transformations by the body utilize energy and produce heat.
What are calories and energy spending?
The production of heat by metabolic processes mirrors events developing as a result of hormonal changes, play of emotions, and stressful influences. Energy spending depends on the level of physical activity. Energy spending at rest is projected to metabolically active cells and tissues. To determine energy expenditure scientists use direct calorimetry or recur to the determination of body dissipated heat. At resting state the body may need about 1 calorie per minute. However, intensive work may require 10 calories per minute. Strange is the fact, but mental work does not influence much upon energy demands. Gaining weight occurs if a person takes in more calories than are spent. Low caloric intake leads to weight loss because the body consumes stored energy to cover immediate requirements. To lose 454 grams of fat tissue it is necessary to create a deficit of 3500 calories.
What are calories and dieting?
Healthy diets allow regulating the food consumption for improving physical condition. It is particularly true for reducing excess of body fat and fighting with obesity. Dieting plans presuppose the reduction of fats, carbohydrates, and proteins. Weight loss can be achieved by creating the energy deficits from 500 to 1000 calories per day. Good diets recommend the consumption of vegetables, fruits, and nuts. Dietary fiber contributes to satiation with low calorie foods.