Overview of Vitamins

Vitamins are chemical substances found in food that are required for normal growth and health of humans. They are essential nutrients that the human body cannot produce. Therefore, adequate intake of vitamins not only protect people against deficiency diseases but also help prevent a number of chronic diseases like heart disease, cancer, birth defects etc. Each vitamin has a range of intake in which it functions optimally. Intakes below and above the range impair health. Eating 5 or more servings of fruits and vegetables per day is a good way to get enough vitamins into the diet. Vitamins act as a co-enzyme and/or regulator of metabolic process. There are 13 known vitamins, most of which are present in foods or supplements. Of the 13 vitamins, 9 are water soluble and 4 are fat soluble. With the exception of vitamin B12, water soluble vitamins can be stored in the body in small amounts. Deficiency diseases therefore develop relatively quickly within weeks. Of the water soluble vitamins, niacin, pyridoxine and vitamin C can cause ill effects if consumed in excess amounts. Fat soluble vitamins are stored in body fat, liver and other parts of the body. Deficiencies of fat soluble vitamins take longer to develop than deficiencies of water-soluble vitamins when intake from food is too low.

A summarized description of the 13 vitamins is given below.

Water Soluble Vitamins

1. Vitamin B1 (Thiamine)
2. Vitamin B2 (Riboflavin)
3. Vitamin B3 (Niacin)
4. Vitamin B6 (Pyridoxin)
5. Vitamin B9 (Folate)
6. Biotin
7. Pantothenic Acid
8. Vitamin C
9. Vitamin B12

Fat Soluble Vitamins

1. Vitamin A
2. Vitamin D
3. Vitamin E
4. Vitamin K