Fiber is the good guy of food. It may help protect against colon cancer and heart disease, and it is your weight-control friend. It slows digestion, helping you to feel fuller longer, and displaces other caloric foods. Best of all, it comes in fruits, vegetables, and whole grains that are loaded with beneficial vitamins and minerals.
But as with protein, don't set your expectations too high, Mattes cautioned.
"Most of the studies showing beneficial effects are based on very large intakes that just aren't realistic for the general population," he said. "The typical American consumes 10 to 14 grams a day. The recommendation is for 25 or more grams, which is a huge departure from one's customary intake."
You might not make it to that goal, but you can boost your fiber-rich vegetable intake fairly painlessly, said Barbara Rolls, Ph.D., professor of nutritional sciences at Pennsylvania State University.
"Grow the amount of vegetables on your plate and shrink everything else," Rolls said. "Toss them in oil and roast them in the oven. Add your favorite veggies to sandwiches, pizza toppings, stews, wherever you can."