Except for vitamin `B_(12)`, all other vitamins group B should supplied regularly in diet. Why ?

Explanation

Group B-vitamins or vitamins B-complex has vitamins `B_(1), B_(2), B_(6)` and `B_(12)` as its constituents. All of them are water soluble. They can be assimilated by the body and are excreated through urine. This means that they have to be regularly supplied to the body. Vitamin `B_(12)` is an exception. Though water soluble, still it can be stored in the liver and can be retained by the body. It therefore, need not be supplied to the body regularly.