Explain about the Importance of Vitamins?

Vitamins are the organic substances that act as coenzyme and/or regulator of metabolic processes. There are 13 known vitamins, most of which are present in foods while some are produced within the body. You would recall from your study in Nutritional Biochemistry Course that depending on the property of solubility, vitamins are divided into two groups, namely, water-soluble and fat-soluble. Water-soluble vitamins include vitamin B-complex, which is a group of B Vitamins, and vitamin C or ascorbic acid while the fat-soluble vitamins comprise of 4 vitamins- A, D, E and K. In this unit, we shall focus on the fat-soluble vitamins. The next unit shall deal with the water-soluble vitamins.

Fat-soluble vitamins A, D, E and K, are termed so because they are found in nature in close association with fatty foods such as butter, cream, vegetable oils, meat, poultry and fish and their products. Though these four vitamins have quite different  properties, this unit discusses low they all share some commonalities such as  mechanism of absorption from intestines, storage of the excess intake and development  of deficiency with inadequate intakes, as well as, toxicity at intakes far in excess of the requirements. The unit also provides information on their requirements, status assessment and interaction with other nutrients.

Objectives

After studying this unit, you will be able to:

• describe the structure and functions of fat-soluble vitamins,
• identify their food sources, bioavailability and consequences of deficiency,
• recognize the recommended amount needed during various physiological stages, and
• Appreciate their importance in relation to other nutrients.