This knowledge could lead to individualized, innovative medical treatment. A practitioner using a new kind of diagnostic tool developed from this information should be able to tell from a simple saliva test whether a patient is likely to be allergic to a drug, will respond to one drug better than another, or is at higher than usual risk of cancer or Alzheimer's disease. Furthermore, producing the right treatment with the first prescription is far more likely. For decades, nutritionists have touted the value of fiber as helping to reduce the risk of cancer, heart disease and diabetes. More recently, distinctions between soluble and insoluble fiber are being made.
Soluble fiber stays in the intestines longer and absorbs more cholesterol.
Insoluble fiber, on the other hand, found in wheat bran, seeds, whole grains, and the skins of vegetables and fruits, serves a different purpose. Insoluble fiber absorbs water, which increases the speed at which waste passes through the body, thus helping to avoid or relieve constipation. Most nutritionists don't worry about the type. Their primary goal is to encourage people to increase their total fiber intake, regardless of the specific type. But the American diet, rich in processed and fast foods, serves up only 12 to 14 grams of fiber a day, only half the recommended amount.