In general, foods are made up of carbohydrates, proteins, and fats, each of which provide a different number of calories: 1  Carbohydrates provide 4 calories per gram. 2  Proteins provide 4 calories per gram. 3  Fats provide 9 calories per gram.
Importance of Water. Water is used for various important purposes: Water in Agriculture. Water plays the most important role in agriculture. Agriculture is impossible without irrigation throughout the crop season. Irrigation ensures proper plant growth.
Article #12. 1  Water is your body's most important nutrient, is involved in every bodily function, and makes up 70- 75% of your total body weight. Water helps you to maintain body temperature, metabolize body fat, aids in digestion, lubricates and cushions organs, transports nutrients, and flushes toxins from your body.