Vitamins and supplements perform many roles in your body to make it function properly. They also convert food into energy, and repair cellular damage. It can be difficult for your body to get all the nutrients it needs from food. No matter what kind of diet you follow, you still lack enough vitamins and supplements.. Getting enough essential nutrients every day, is crucial for keeping nutrient levels where they should be, to provide benefits for your body. Taking a multi vitamin daily, will help your body to get most of the vitamins your body needs to function.