Everything You Need to Know About Vitamins: Definition and Classification

Vitamins are organic compounds that are essential for normal growth and development, maintenance of good health, and prevention of diseases. 

They are required in small amounts in the diet, as the body cannot produce them on its own in sufficient quantities. Vitamins play a vital role in various bodily functions, such as metabolism, immunity, vision, and blood clotting.

There are two types of vitamins: fat-soluble and water-soluble. Fat-soluble vitamins (vitamins A, D, E, and K) are stored in the body's fat tissues and liver, and can accumulate to toxic levels if consumed in excess. Water-soluble vitamins (vitamins B and C) are not stored in the body and are excreted in urine if consumed in excess.

Vitamins are found in a wide variety of foods, including fruits, vegetables, grains, dairy, and meats. Different vitamins have different properties and functions in the body. For example, vitamin A is important for vision and skin health, vitamin D is important for bone health, and vitamin C is important for immune function and collagen synthesis. Each vitamin has a specific daily recommended intake, which varies depending on age, sex, and other factors.