Monday February 13, 2012
Foods high in Insoluble fibre:
Wheat is a plant that is harvested to make flour. The bran is the outer hull that covers the kernel. Foods high in insoluble fiber contain the kernel and the bran, including wheat bran, whole wheat bread and wheat cereal. Plain wheat without the bran, like processed flour, does not contain insoluble fiber. Other types of whole grains, the kind that include the bran as well as the kernel, also contain insoluble fiber. Rye and brown rice are good sources of insoluble fiber.
FruitsCertain fruits contain insoluble fiber. Think of foods with rough or stringy peels or hulls, or seeds. They contain fiber that cannot be broken down in the digestive tract and pass through unchanged. Apple skin contains a large amount of insoluble fiber. Other fruits and vegetables that contain some insoluble fiber are cherries, grapes, pineapple, rhubarb, oranges, melons, date, prunes and berries.
VegetablesMost raw vegetables contain some amount of insoluble fiber. Vegetables with the highest amounts are turnips, beets, cauliflower, cabbage, Brussels sprouts and carrots. Leafy greens, broccoli, green beans, cucumbers, onions, sprouts, celery, tomatoes, eggplant, bell peppers and corn also contain some insoluble fiber. For best results, vegetables should be eaten raw as cooking breaks down some of the cellular structure.
Beans, Seeds and NutsBeans come to many people's mind when fiber is mentioned. The tough, yet flexible outer shell of most beans and other legumes contain valuable insoluble fiber. This type of fiber is also found in seeds, such as pumpkin and flax, nuts, such as peanuts, walnuts, cashews, and almonds, as well as popcorn and lentils.
Foods high in soluble fibre:
Oats get the most press for being high in soluble fiber, and rightly so. One cup of oatmeal contains 2 g of soluble fiber, half of its total fiber content. Oat bran also has 2 g of soluble fiber per cup. Barley and bulgur are also good sources, with 2 g per cup, although both have more insoluble fiber so the ratio is higher between the soluble and insoluble types. Wheat bran and cracked wheat have only trace amounts of soluble fiber, although their insoluble fiber content is high.
Legumes and NutsLegumes are a wonderful source of both soluble and insoluble fiber, but different types have widely differing amounts and ratios of the two. Kidney beans have about 6 g of soluble fiber per cup, and 12 g of total fiber. A cup of lima beans contains 6 g and a cup of navy beans has 4 g of soluble fiber. Cooked green peas have 2 g per cup. As far as nuts go, a half-cup of dry roasted peanuts is a good choice, with 2 g of soluble fiber, but walnuts and filberts have only trace amounts.
FruitFresh pears are one of the best fruits for soluble fiber, with 3 g per medium fruit. A medium apple has only 1 g of soluble fiber, but also contains 3 g of insoluble fiber as well. A banana, peach and orange each have 1 g of soluble fiber per fruit. Three prunes provide a total of 1 g of soluble and 2 g of insoluble fiber. Cherries, dates, grapes and pineapple have only trace amounts of soluble fiber, although they do contain insoluble fiber.
VegetablesVegetables tend to be better known for their insoluble fiber content, but some veggies do contain respectable levels of soluble fiber, too. Parsnips, winter squash and Brussels sprouts are all good sources of soluble fiber, with 4 g per cup in each of these vegetables. Vegetables containing 2 g of soluble fiber per cup include string beans, cabbage, carrots, broccoli, zucchini and turnips. Tomatoes, corn and cauliflower provide only trace amounts of soluble fiber.
Foods high in resistant starch:Beans
Resistant starch is a third type of fiber that is neither soluble or insoluble. Beans and legumes are a source of this fiber, carrying an RS1 classification. The Commonwealth Scientific and Industrial Research Organisation of Australia says that some legumes may have as much as 10 percent resistant starch content. Beans that fit into the RS1 category may include kidney, split pea, soy, black-eyed peas, lentils, fava, pinto, lima, mung, calico, navy and Italian beans.
Cooked and ChilledSome foods' resistant starch content is increased by chilling. Cooling the food allows resistant starch crystals to form, which the small intestine cannot process. The small intestine is where most of the absorption of nutrients take place. Three major foods fit into this category and have an RS3 classification. They are cooked and chilled potatoes, pasta and rice.
Whole Grains and Other FoodsUnprocessed whole grains and seeds are graded as RS1. Harvard Medical School includes barley, bulgur or cracked wheat, amaranth, oats, quinoa, flaxseed, rye, millet and spelt as whole grains. Other foods that are high in resistant starch and have a RS2 rating are moderately green bananas, uncooked potatoes and high amylose corn. High amylose corn is a hybrid that is used to make high amylose cornstarch.