Nutrients are chemical components of food that supply nourishment to the body. They are required by the body in the right amounts and they must be eaten regularly. Each nutrient –proteins, fats, vitamins and water – performs a specific function in our body. Cellulose, though not a nutrient itself, plays an important role in the physiology of digestion. Hence it is considered to be a vital nutritional factor.
FUNCTIONS OF NUTRIENTS-
- Supply energy to the body
- Build and repair body tissues
- Regulate body processes
Carbohydrates and fats primarily supply energy. Proteins provide functional and structural materials and supply energy when the dietary intake of carbohydrates and fats is low. Vitamins and minerals, along with water, help to regulate the body processes such as respiration, reproduction, circulation, metabolism, digestion, absorption and elimination. These processes take place continuously in our body without our being conscious of them. Water which constitutes about 58% of the body weight is found in all the tissues. Its importance in the body cannot be underestimated. A man can live without food for several days but cannot survive without water for even a few days. It is a solvent and all enzymatic activities require water. Hence metabolism in the body and all physiological processes require water. It plays an important role in carrying nutrients to all the tissues and removing wastes from them. Hence an average person must drink at least six to eight glasses of water or its equivalent in a day.
Cellulose, though not a digestive part of the diet, is an indispensable one. Cellulose or dietary fiber helps in the process of elimination of wastes in the form of stools. It does so, by binding the stools, along with water. And also stimulates the gastro-intestinal tract which helps early defecation.