DEAR DOCTOR K: I recently read that fiber doesn’t prevent colorectal cancer. So is a high-fiber diet good for you or not?
DEAR READER: Fiber was once thought to play an important role in preventing colon cancer. As you’ve read, that turned out not to be the case.
However, diets rich in fiber are still good for your health in many other ways. For example, we know that fiber slightly reduces bad (LDL) cholesterol. It improves insulin resistance (a common precursor to diabetes). And it is linked to a lower rate of heart disease and obesity.
In addition, fiber increases the bulk of foods and creates a feeling of fullness. As a result, fiber may help you avoid overeating and becoming overweight.
Fruits, vegetables and whole-grain foods such as whole-wheat bread, whole-grain cereals, brown rice, bran and oats are all good sources of fiber. In particular, split peas, red kidney beans, raspberries, whole-wheat spaghetti, pears, broccoli and apples are all good choices.
You can also consume fiber in over-the-counter supplements, which provide some of the same benefits as fiber in foods.
However, the scientific evidence for the health benefits of fiber comes primarily from studies of fiber in food, not fiber in supplements. And the fiber-rich foods I listed earlier also contain lots of other health-giving substances.
Bottom line: Although fiber probably does not prevent colon cancer, it really is good for your health in other ways. A diet full of fiber-rich foods will bring you loads of benefits.