Chengcheng Jia NUTR 417 Supplement Paper The Soluble Dietary Fiber: Inulin Introduction and Supplement Background: Dietary fiber is defend as the edible parts of plant or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine (American Association of Cereal Chemists Dietary Fiber Definition Committee, 2001). The main different insoluble fiber and soluble fiber is that insoluble is unable to form gel when dissolved in water and has only limited fermentation in the colon. Inulin is a soluble fiber that can form gel and well-fermented in the colon. America promotes the consumption of more vegetables and fruits. Unfortunately, American population on average consumes only half of the recommended amount of fiber daily (cite cite). For purpose of investigating the benefits and feasibility of adding more fiber in daily diet, Metamucil Clear & Natural Fiber Supplement Powder (unflavored) are selected as a supplement. According to the website, the soluble fiber inulin obtained from chicory roots is the only ingredient in the product. They claim that by purchasing this particular product is an easy way to put fiber into favorite beverages and foods because it is flavorless, tasteless and grit-free. In addition, the benefits of fiber are supported by a link to National Fiber Council (NFC) s website which provided a NFC fiber review paper. According to Health benefits of dietary fiber, fiber reduces the risk of coronary heart disease, stroke, hypertension, diabetes, obesity, and certain gastrointestinal disorder; increased consumption of fiber also promotes weight loss, lowers of blood pressure, and shows blood glucose control in diabetes (cite cite). As the review further examines the benefits of fiber, type of the fiber appears to be an issue
because the type of fiber is not very clearly stated in the review article. Therefore, the main ingredient in the package, inulin, was not mentioned in most of the review articles. Nevertheless, there is one other review article specifically reviews the functional and health attributes of inulin dietary fiber. It concludes that inulin, a neural-taste and colorless soluble fiber, may have the abilities to reduce calories, stimulate the growth of beneficial bacteria in the colon, relieve constipation and promote regularity, influence lipid metabolism, enhance mineral bioavailability (calcium, magnesium, and iron), impact blood glucose and cancer/tumor growth. Three potential benefits of inulin is further examined in the following: Inulin and Constipation Even though fiber supplement has always been associated as a laxation, the effect on laxation of soluble fiber is less well-known than insoluble fibers. In a human double-blind trail in elderlies (aging from 50-70 years old), bowel movement frequency was significantly increased through the administration of 15 grams of chicory inulin daily when compared to the controlled group (cite cite). In addition, quality of life was increased despite some side-effects of fiber (flatulence, bloating, abdominal pain or diarrhea) were experienced by subjects. Aging is associated with several physiological changes in gastrointestinal function and diseases such as a decrease in acid secretion by the gastric mucosa and chronic primary constipation (cite cite). Common recommendation of solving constipation was to increase the intake of dietary fiber and fluid. However, insoluble fibers are not easily dispersible in foods, changes in taste and dental condition may also occur. Thus, inulin was a good choice for the elderly who experience chronic constipation. Inulin, Release of Gut Peptides and Gastric Emptying Rates In addition to the relief of constipation, inulin may also have an effect of reducing triglyceride and glucose in the blood via slowing in gastric emptying rate (cite cite). The
human study involving 20 healthy young male volunteers and 5 week s insulin enriched pasta concluded that introduction of 100 grams of 11 percent inulin-enriched pasta triggered more release of gut peptides (Neurotensin (NT) and Somatostain (SS)) and a longer gastric empty time. Peptides NT and SS are involved in slowing gastric empty rate by affecting the gastro duodenal motility. At this dose of inulin fiber, no side effects or gastrointestinal symptoms were recorded, and the compliance to the study was high. Inulin, Fat Replacer and Calorie Reduction Inulin, as a soluble fiber, is capable of forming a viscous gel network when thoroughly mixed with water or other liquid (review cite). In order to evaluate the inulin s ability as a fat replacer, a study was designed to replace the milk fat in a yogurt (cite cite). Three yogurt products were compared in the study: yogurt with 2.7% inulin, yogurt with 0.7% inulin and yogurt produced from full-fat milk (3.2% of fat). Inulin-replaced yogurts were compared with the 3.2% milk fat yogurt in number of yogurt bacteria, acidity, apparent viscosity and sensory properties (color and appearance, flavor, texture, and taste) using a six-point scale. The mean total score indicates that yogurt containing 2.7% of inulin has a score almost as high as the control yogurt produced from full-fat milk. The slight difference could be eliminated by adjusting the total solids in the sample. Therefore, inulin could be a fat replacer in low-fat yogurt without affecting the original high-fat properties of yogurt produced from full-fat milk. Discussion and Conclusion Functional food is defined as the food that beneficially affect one or more target functions in the body, beyond adequate nutritional effects, in a way which is relevant to either the state of well-being and health or the reduction of risk of a disease. Therefore, inulin is not only dietary fiber, but also a functional food. It is not only resistant to digestion in the upper gastrointestinal tract, but also it is fermented by colonic bacteria in the colon, where short chain fatty acids is produced and ph is decreased. According to
the instruction of use online, for adults (12 years and older) the recommended usage is one teaspoon, up to three times daily, which is 15 grams of inulin per day. That is about half of recommended total fiber intake since the recommendation is 14 grams fiber per 1000 kcal. Since inulin can t be digested by small intestine, the only place that inulin can contribute calories is the colon via fermentation: 1.5 kcal/g of energy instead of 4.0 kcal/g for other carbohydrates. Therefore, inulin can be reviewed as a calorie deducting product. Inulin s gel-forming property can also apply to calorie reduction by being a fat replace in ice-cream, yogurts and backed foods, etc. As a fat replacement, the flavor, texture and taste of foods may be adjusted to the original mouth feel by experimenting the correct dosage needed to recreate the original product. This might benefit society as whole because if massive production of fat-replaced items occur, people might benefit in weight loss and weight control. However, long-term physiological and psychological effects of the fat-replacer need more research to support the proposed benefit. Furthermore, 3 servings of supplement fiber can be easily added to beverage and other foods. It s not a difficult dietary change for people to follow and it s not time-consuming. In conclusion, I would recommend Metamucil Clear & Natural Fiber Supplement Powder (unflavored) to elderly who experiences chronic constipation, individuals who are trying to lose weight, but don t want to eliminate the taste of baking goods, icecreams, or yogurts. However, the recommended amount is 15 grams soluble fiber per day. The amount might be a little too much because fiber intake can be obtained from real foods such as various vegetables and fruits. Over-consumption of fiber will result in negative consequences such as flatulence, bloating, abdominal pain or diarrhea. Therefore, for people who are already on a diet consisting adequate intake of vegetables and fruits, this supplement is not recommended.
Reference: Elrayeh A, Yildiz G. Effects of inulin and β-glucan supplementation in broiler diets on growth performance, serum cholesterol, intestinal length, and immune system. Turkish Journal Of Veterinary & Animal Sciences [serial online]. August 2012;36(4):388-321. Seifert S, Watzl B. Inulin and Oligofructose: Review of Experimental Data on Immune Modulation. Journal Of Nutrition [serial online]. November 2, 2007;137:2563S-2567S. Kalyani Nair K, Kharb S, Thompkinson D. Inulin Dietary Fiber with Functional and Health Attributes A Review. Food Reviews International [serial online]. April 2010;26(2):189-203. Tarini J, Wolever T. The fermentable fibre inulin increases postprandial serum short-chain fatty acids and reduces free-fatty acids and ghrelin in healthy subjects. Applied Physiology, Nutrition & Metabolism [serial online]. February 2010;35(1):9-16. Russo F, Clemente C, Riezzo G, et al. Effects of a diet with inulin-enriched pasta on gut peptides and gastric emptying rates in healthy young volunteers. European Journal Of Nutrition [serial online]. June 2011;50(4):271-277. MODZELEWSKA-KAPITUŁA M, KŁĘBUKOWSKA L. Investigation of the potential for using inulin HPX as a fat replacer in yoghurt production. International Journal Of Dairy Technology [serial online]. May 2009;62(2):209-214. Grassi M, Petraccia L, Fraioli A, et al. Changes, functional disorders, and diseases in the gastrointestinal tract of elderly. Nutricion Hospitalaria [serial online]. July 2011;26(4):659-668. Table: Supplement vs. Food Food [a] Name Frontier Natural Products Organic Roasted [b] Amount 1 lb./package 151 servings of chicory per container; root contains 1 grams [c] Cost $12.5/packa ge [d] Price per dosage $0.08 per 1 teaspoon (151 total servings) [e] # of servings to obtain 100% DV (or DRI) 15 servings for 15 grams of inulin in roots [f] Price to obtain 100% DV (or DRI) $1.2 per 15 servings
Chicory Root of inulin per serving; daily dose=1x15=15 servings Suppl emen t Metamucil Clear & Natural Fiber Suppleme nt Powder (unflavore d) 11.7 oz/container 57 servings per container; 3 serving per day= 15 grams inulin from chicory root $10.89/cont ainer $0.19 per 1 teaspoon (57 total servings) No DRI for soluble fiber, but total fiber is 25 grams women 30 grams men (14 grams/1000 kcal) Therefore, 15 grams per day is enough for soluble fiber $0.57 per 3 servings 3 servings for 15 grams of inulin