why do we need non starch polysaccharides
Nonstarch polysaccharides arenБt as complicated as they sound -- that term is just another name for a few types of fiber. What sets one carbohydrate apart from another is its size and structure, which in turn determines how, or if, itБs digested. Nonstarch polysaccharides are large-sized carbs that aren't digested, but some are fermented once they reach the large intestine. Simple carbohydrates consist of one or two units of sugar, or saccharide, while complex carbs contain three or more sugars linked together. Polysaccharides have at least 10 sugars and may have many thousands of sugar molecules. Starches are polysaccharides, but they're digestible because you have the enzymes needed to break the bonds between each sugar molecule. The human body doesn't have the enzymes required to cleave the type of bond holding polysaccharides together, so they're not digested. These nondigestable polysaccharides -- the nonstarch polysaccharides -- pass through your stomach and small intestine intact. Nonstarch polysaccharides come from plants, where they help form structural parts such as cell walls. The primary types of nonstarch polysaccharides are pectin, cellulose, gums and hemicelluloses. The hemicellulose group includes more than five different polysaccharides, including beta-glucan. Since nonstarch polysaccharides are types of fiber, theyБre further grouped according to the more commonly known types of fiber, soluble and insoluble.
Cellulose falls into the insoluble group, which means itБs the type of fiber that prevents constipation. Hemicelluloses, pectin and gums are all soluble fibers. They help lower cholesterol and keep blood sugar balanced. Most types of soluble fiber are also fermented by bacteria in the large intestine, a process that produces energy and short-chain fatty acids that promote intestinal health. Vegetables are one of the best sources of cellulose. If you choose veggies with the highest amount of total fiber, such as broccoli, carrots, Brussels sprouts and green peas, you'll get the most cellulose because it accounts for a third of their total fiber. Fruits are the best-known sources of pectin, with apples, oranges and grapefruit at the top of the list. Fruits, vegetables, legumes and nuts also provide hemicelluloses. Oats are such good sources of beta-glucan that theyБre approved to carry a health claim stating that they can help reduce cholesterol, according to a report published in БNutrition ReviewsБ in June 2011. Gums, such as guar gum and psyllium, are usually extracted from seeds and used as food additives or supplements. If you need to lower cholesterol, you may want to boost the soluble fiber in your diet by consuming beans, peas, lentils and oats.
Otherwise, just focus on getting the required daily intake for fiber rather than worrying about which type of fiber you consume. Even though some foods are better sources of one type of fiber, whole foods contain several types of soluble and insoluble fiber. If your diet includes a variety of vegetables, fruits, beans, whole grains and nuts, you will get all the different types. Women should consume 25 grams of total fiber daily, while men should aim for 38 grams.
Nonstarch polysaccharides (NSPs) occur naturally in many foods. The physiochemical and biological properties of these compounds correspond to dietary fiber. Nonstarch polysaccharides show various physiological effects in the small and large intestine and therefore have important health implications for humans. The remarkable properties of dietary NSPs are water dispersibility, viscosity effect, bulk, and fermentibility into short chain fatty acids (SCFAs). These features may lead to diminished risk of serious diet related diseases which are major problems in Western countries and are emerging in developing countries with greater affluence. These conditions include coronary heart disease, colo-rectal cancer, inflammatory bowel disease, breast cancer, tumor formation, mineral related abnormalities, and disordered laxation.
Insoluble NSPs (cellulose and hemicellulose) are effective laxatives whereas soluble NSPs (especially mixed-link О-glucans) lower plasma cholesterol levels and help to normalize blood glucose and insulin levels, making these kinds of polysaccharides a part of dietary plans to treat cardiovascular diseases and Type 2 diabetes. Moreover, a major proportion of dietary NSPs escapes the small intestine nearly intact, and is fermented into SCFAs by commensal microflora present in the colon and cecum and promotes normal laxation. Short chain fatty acids have a number of health promoting effects and are particularly effective in promoting large bowel function. Certain NSPs through their fermented products may promote the growth of specific beneficial colonic bacteria which offer a prebiotic effect. Various modes of action of NSPs as therapeutic agent have been proposed in the present review. In addition, NSPs based films and coatings for packaging and wrapping are of commercial interest because they are compatible with several types of food products. However, much of the physiological and nutritional impact of NSPs and the mechanism involved is not fully understood and even the recommendation on the dose of different dietary NSPs intake among different age groups needs to be studied.
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