The chemical components present in food in either large or small quantities are called nutrients.

They are essential for the normal functioning of the human body.

They include:

 Carbohydrates

 Proteins

 Fats and Lipids

 Vitamins

 Minerals

 Water

Carbohydrates:
Carbohydrates are naturally occurring bulk nutrients present in many foods. They are sugars or polymers of sugar. They are the main providers of energy in the Indian diet.Some of the common ones include glucose, fructose, galactose, sucrose, lactose, maltose, starch and the non- starch polysaccharides (NSP) also known as fibre. Common examples of foods rich in carbohydrates include cereals, pulse and sugar and jaggery.

Proteins:
Proteins are naturally occurring substances, which contain nitrogen and perform all the three major functions of nutrients. They help in growth, maintenance and repair of body tissue. All proteins are made up of amino acids. Meat, fish, egg, milk, cheese, pulses, soya bean and mushrooms are good sources of protein.

Lipids and Fats:
Lipids are generally esters of fatty acids. Like carbohydrates, they contain carbon, hydrogen and oxygen. They are energy providers as one gram of fat provides more than double the energy of one gram of carbohydrate or protein. Nuts and oilseeds, vegetable oils and butter are good sources of fats and lipids.

Vitamins:
Vitamins are essentially organic compounds, which are vital for the normal functioning of the human body. Vitamins are either fat-soluble or water-soluble. All fruits and vegetables are good sources of Vitamins. Cereals, pulses and nuts are also good sources of certain vitamins.

Minerals:
Dietary minerals are generally trace elements, which are required in very small amounts for the normal functioning of the human body. Macro minerals like calcium, phosphorous, iron, sodium, chloride and sulphur are required in relatively larger quantities and micro minerals or trace elements like zinc, selenium, copper, cobalt etc are required in smaller quantities.

Water:
Water is an essential nutrient. It is not only considered as the universal solvent but is also essential for almost all bodily functions.