Refined foods supply energy but do not supply vitamins and minerals, so the process of turning the refined carbohydrate into energy, the body must use its won store of vitamins and minerals. Vitamins and minerals are involved in nearly every function the body performs. A vegetarian diet can readily supply an abundance of these nutrients. Vitamin C improves absorption of iron from plant food. Vitamins A, C, and E are thought to be protective against some cancers.
Beta carotene reduces risk of heart disease.
Fiber serves a number of functions in the body. It acts as a broom to sweep clean the digestive tract. Fiber adds bulk to the diet, diluting energy so we can eat plenty without consuming excessive calories. Fiber also dilutes the concentration of nutrients absorbed during digestion. A more even concentration of nutrients is absorbed.