What are vitamins essential for in the body?

Vitamins play a crucial role in regulating numerous body processes, which is why the answer focuses on this function. Each vitamin has specific roles that contribute to the body's physiological functions. For instance, vitamins assist in immune function, energy production, blood clotting, and cellular repair, among other processes. They act as coenzymes, helping to catalyze biochemical reactions essential for maintaining homeostasis and overall health.

The other options generally describe functions not directly associated with vitamins. While vitamins can have indirect roles in energy metabolism, they do not supply energy themselves; instead, carbohydrates and fats serve this purpose. Vitamins also do not provide structural support to cells; that role is primarily fulfilled by proteins and other cellular components. Lastly, the storage and release of glucose is primarily managed by carbohydrates and hormones like insulin, not vitamins. Thus, acknowledging the essential regulatory functions of vitamins helps underscore their importance in maintaining a healthy body.