The science that deals with the study of the functions of the nutrients is termed as nutrition. Carbohydrates, proteins and fats are macronutrients and vitamins and minerals constitute the micronutrients. Vitamins could be broadly classified as fat soluble and water soluble vitamins. Vitamin A, D, E and K are termed as fat soluble vitamins whereas vitamin B complex and vitamin C are water soluble.

• Vitamin A:

Vitamin A is needed for healthy growth of epithelium, healthy eyes, and resistance of the body. It is found abundant in foods such as carrots, spinach, cabbage, papaya, liver and egg yolk. Night blindness is the deficiency disease of vitamin A.

• Vitamin D:

It helps in the absorption of calcium and phosphorus, strengthening of bones and teeth and also makes the hair shining. The rich food sources are cod liver oil, butter, ghee, egg, milk and sunlight. The inadequate absorption of this vitamin in the body results in rickets and osteomalacia.

• Vitamin E:

Vitamin E helps to keep the reproductive system healthy. It also protects the pelvic regions in the women. It is also necessary for the ligament and muscles. Soybean , coconut oil, tomato, carrot, peanuts, green leafy vegetables are good sources of vitamin E. Deficiency of vitamin E results in miscarriage and reproductive failure.

• Vitamin K:

It prevents skin disease, helps in clotting of blood. It is also necessary for prothrombin production. Cauliflower, butter, egg-yellow, potato, green leafy vegetables, soybean, tomato, and spinach are good sources of this vitamin.

• Vitamin B1 (Thiamine):

Main functions of vitamin B1 are body growth, release of energy from the metabolism of carbohydrates, protection against heart disease. The food sources of this vitamin are yeast, soybean, green leafy vegetables, dry fruits and nuts. Pain and weakness are the symptoms of thiamine deficiency.

• Vitamin B2 (Riboflavin):

Riboflavin protects the body against skin diseases, helps in oxidation with phosphorus and protein, necessary for protection and vigor of the body. Milk, egg, liver, yeast, cheese, green leafy vegetables and meat are rich sources of this vitamin. Blurring of vision and soreness of eyes, cracking of skin are the common diseases accompanying the deficiency of this vitamin.

• Niacin:

It prevents mental fatigue, keeps skin healthy, and provides immunity, strength to nervous system and digestive tract. Yeast, groundnut, whole cereal pulses are rich sources of niacin. Its deficiency leads to dementia, diarrhea and dementia.

• Vitamin B6 (Nicotinic acid):

It keeps the gums and tongue healthy, helps in the metabolism of protein and fatty acid. Germinated cereals, soybean, peanuts, green leafy vegetables, meat, milk and. Anemia, angular stomatitis and pellagra are the deficiency diseases.

• Vitamin B12:

Vitamin B12 is commonly found in yeast, liver, fish, and eggs. Its deficiency leads to pernicious anemia.

• Vitamin C (Ascorbic acid):

Vitamin C is the important vitamin responsible for immunity against infectious diseases. It keeps the gum and throat healthy, gives sharp eyesight and strengthens blood vessels. It is found rich in citrus fruits, amla and guava. The most common disease of vitamin C deficiency is scurvy.