Define vitamin?/Write down the types of vitamin/Classify vitamins

 Definitions: Vitamins are organic non-calorigenic nutrients that are required in small quantities for man different biochemical function, which generally cannot be synthesized by the body and must therefore, supplied by the diet.
Or Vitamin B- complex are chemical substance required by the body very small amounts, they do not yield energy but gives us protective manner.

Classification: According to solubility-Vitamins are classified into two main group.
1.       Water soluble vitamins-Vitamins B-Complex-Vitamins C.
2.       Fat soluble vitamins-Vitamin A, Vitamin E, Vitamin D & Vitamin K.
Difference vitamins between water soluble and fat soluble
Fat soluble vitamins.

Difference between fat soluble and water soluble vitamins

Fat soluble vitamins	Water soluble vitamins
1. Soluble in fat	1. Soluble in water
2. Bile salts & Fats are essential for their absorption	2. They are easily absorbed.
3. Are not precursor of co-enzymes ( except vit-k)	3. Many of them are precursors of co-enzymes.
4. significant amounts are stored in the Liver & adipose tissue	4. Small amounts are stored in the body.
5. They are not readily excreted in the urine.	5. When ingested in excess of the body’s requirement they readily excreted in the urine.
6. Excess amounts in the body is toxic (specially vit-A & D)	6. As excreted in the urine, excess amount is not toxic.