Recent studies have shown that multivitamins are less effective than getting the real thing from your fruits and vegetables. This is because supplements are usually artificially synthesized rather than harvested from organic materials. Usually, vitamin supplements are recommended when there is deficiency or there is a need for a higher dose than the RDA. As much as possible, you should consider eating healthy and not having to rely on supplements to reach your recommended daily allowance (RDA) of vitamins and minerals. You should consult a dietitian or nutritionist to help you with this, or research about good diets on the net or on books.