Naturally Fiber-rich Foods

Dietary fiber includes parts of food that the body cannot absorb or digest. Instead, the fiber passes through the digestive system and aids in the elimination of waste. There are two types of fiber--soluble and insoluble. Soluble fiber dissolves in water to form a gel, which slows down digestion. Insoluble fiber speeds the passage of food through the stomach and adds bulk to the stool. Both types of fiber are necessary for healthy digestion. MayoClinic.com reports that a high-fiber diet increases bowel health, lowers cholesterol, controls blood sugar and may even promote weight loss.

Grains and Grain Products

Grains and grain products are naturally rich in both soluble and insoluble fiber. According to the University of Maryland Medical Center, oat bran and barley contain soluble fiber, and wheat bran and whole grains contain insoluble fiber. Other common grain products high in fiber include whole-wheat bread, bran cereals, carob flour, whole-wheat pasta, wheat germ, bran muffins, old-fashioned or quick-cooking oatmeal and brown rice. One slice of whole-wheat bread contains about 1.9 g of fiber, and 1 cup cooked whole-wheat spaghetti provides about 6 g, says MayoClinic.com.

Fruits and Vegetables

Fruits and vegetables are particularly rich sources of soluble and insoluble fiber. Apples, pears and strawberries are high in soluble fiber, and broccoli, carrots, spinach, prunes and potatoes are high in insoluble fiber, according to Aetna InteliHealth. Other fruits and vegetables that contain large amounts of fiber include raspberries, blackberries, bananas, oranges, figs, raisins, dried apricots, dried pears, coconut, artichoke, turnip greens, sweet corn, olives, onions, peppers and Brussels sprouts. Raspberries contain more fiber than other fruits, about 8 g of fiber in each 1-cup serving, reports MayoClinic.com. Artichokes are highest in fiber among the vegetables, providing about 10.3 g each.

Nuts, Seeds and Legumes

Nuts, seeds and legumes rich in fiber include split peas, lentils, black beans, lima beans, sunflower seeds, flaxseed, almonds, pistachios and pecans, according to MayoClinic.com. These foods provide primarily soluble fiber. Split peas contain the most fiber compared to other legumes, about 16.3 g in each 1-cup serving. Nuts typically provide less fiber than beans and seeds. Pecans, for example, provide about 2.7 g in each 1-oz. serving, and pistachios provide about 2.9 g in a 1-oz. serving.

Other Foods

Several culinary herbs and spices also contain large amounts of fiber, explains Audrey Ensminger in the "Foods and Nutrition Encyclopedia." Coriander seed, cinnamon, chili powder, allspice, paprika, rosemary, thyme and marjoram are among the richest in fiber. Herbs and spices are typically only eaten in very small amounts, however, and don't contribute much fiber content to the diet. Other foods that provide fiber include cocoa powder, psyllium husks and air-popped popcorn.