For example, some ingredients may be safe in products such as cleansers that we wash off the skin immediately, but not in products that we leave on the skin for hours. Similarly, ingredients that are safe for use on the hair or nails may be unsafe when used on the skin or near the eyes.
Carbohydrates are the main energy source for the brain. Without carbohydrates, the body could not function properly. Sources include fruits, breads and grains, starchy vegetables and sugars. Make at least half of the grains you consume whole grains.
Vitamins, minerals, fiber, and water do not provide energy, but are required for other reasons. A third class of dietary material, fiber (i.e., nondigestible material such as cellulose), seems also to be required, for both mechanical and biochemical reasons, though the exact reasons remain unclear.