Is excessive consumption of vitamin tablets harmful?

Vitamin preparations are to be taken only when there is documented, proven case of deficiency. Normal food contains enough vitamins and hence supplementation is seldom required. It is wrongly believed that vitamins do not cause side effects. Firstly, when taken in excess some vitamins are thrown out by the body in urine such as vitamin B-complex. Secondly, the daily requirement of Vitamin A is about 2250 units which is adequately supplied by diet while Supradyn contains 10,000 units! Such large quantities can cause hypervitaminosis.