The word 'vitamin' has its root in 'vitamine' that means vital amine. Vitamins are powerful organic compounds found mainly in the food that we eat. Vitamins are essential for all human beings because they help cells and tissues to perform basic functions. Basically, vitamins are required for the growth of the body. There are two types of vitamins- the water soluble vitamins and the fat soluble vitamins. Fat soluble vitamins are also called hormones. All the commonly known vitamins are water soluble vitamins, of which vitamin C or ascorbic acid is the most common. Earlier it was believed that all these vitamins belong to one group called B complex as they were all found in the same source. Later they were categorized as different vitamins. Vitamin A, B1, B3, B5, B9, D, E, H, K, P, Choline and Inositol are some of the other vitamins. Few of these vitamins are known by their biological names, like vitamin B1 is known as thiamine and vitamin H, Biotin. Vitamins form an essential component of the balanced diet that we eat. People with chronic illnesses are advised to take vitamin supplements by their doctors. Pregnant women and people suffering from bowel disorders need to watch out their vitamin intake. Bowel disorder retards the absorption of fat soluble vitamin. Folic acid is prescribed for a person suffering from thalassaemia. Patients with pernicious anemia have to be given injections of vitamin B12 because of its acute deficiency in their body. We need small amounts of these vitamins on regular basis to help the body function smoothly and remain healthy. These vitamins help the organs to carry out their individual functions. In the absence of these vitamins, our body falls sick and suffers from vitamin deficiency diseases. There are enough vitamins present in our foods but if we don't eat a balanced diet the external supplements will do the needful. Vitamins are useful and mandatory for the body, but excess of everything is bad. Even vitamins taken in excess can cause severe damage to the body. For instance, the body needs only 400 to 800 units of vitamin D in a day. If this amount is exceeded, too much calcium gets absorbed by the bloodstream, which can damage the kidneys. Moreover, supplements can never replace the healthy diets, so it's better to take vitamin-rich diet than take supplements. Last word of caution: Do not take vitamins by gathering information from here and there. Consult your doctor. Remember, little knowledge is a dangerous thing.