Foods containing roughage, or fiber, include fruits, vegetables, cereals and grains, nuts and legumes and even some canned foods. Among fruits, raspberries offer the most fiber, with 8 grams of fiber in each 1 cup serving. Apples and pears come next; a medium-sized fruit of either variety, with the skin on, contains approximately 4 to 5 grams of fiber.
Bananas, oranges and strawberries also pack lots of fiber. They provide approximately 3 grams of fiber for each serving size, which equates to one medium banana or orange and 1 cup of strawberries. Tropical fruits also have high fiber contents: mangoes and persimmons have 5 to 6 grams each, while 1 cup of guava may contain 9 grams of fiber.
In addition to fruit, legumes, nuts and seeds also have high fiber contents. For cooked beans and legumes, 1 cup of lima beans, black beans or lentils offers roughly 13, 15 or 16 grams of fiber, while 1 cup of cooked split peas provides over 16 grams. In the nut family, 1 ounce of pecans or pistachios provides around 3 grams of fiber, while 1 ounce of almonds packs roughly 3.5 grams.
Among vegetables, dark leafy greens are generally the best sources of fiber. An artichoke contains approximately 10 grams of fiber, while 1 cup of cooked green peas offers slightly less. Among grains, whole-wheat pastas and barley pack the most fiber, offering 6 grams in each cooked cup.