| Health and nutrition experts all agree that eating a good breakfast is important. A traditional breakfast of cereal or other grain-based foods, such as pancakes or waffles, with fruit can easily begin one’s journey toward an optimum fiber intake — something that most Americans do not achieve. Too frequently in our convenience-oriented and eat-on-the-go culture, breakfast just doesn’t happen, or if it does, it consists of high-sugar, high-fat foods with little, if any, dietary fiber. Fiber’s role in achieving health and preventing disease is not entirely clear. For example, in recent months, a number of studies examining the relationship of high-fiber foods and colorectal cancer yielded contradictory results. However, viscous fibers, such as the soluble fibers in oats and psyllium, are recognized as cholesterol-lowering agents and are associated with lower glycemic response and insulin demand, thus indicating a role in diabetes prevention and management. In terms of gastrointestinal health, the part fiber plays in normal laxation is indisputable, leading to its importance in management and treatment of constipation and diverticulosis. Based on epidemiological and observational studies, other potential benefits from fiber include protection against duodenal and breast cancers, and improvement of immune function. The nutrient that isn’tFor many years, fiber’s contribution to health wasn’t recognized because, in reality, fiber is not a nutrient. It never enters the body, per se, and no direct blood or biochemical markers identify its presence or impact. Its significance is derived from observations or associations with good or bad health outcomes. Thus, identifying just what constitutes a fiber and what it does physiologically is not an easy task. The most basic definition for fiber is based on what it isn’t — digested or absorbed. Many compounds in foods may meet this definition, but what makes a substance a fiber is its ability to change the environment in the gastrointestinal tract through viscosity and/or fermentation. Measuring fiber in food has evolved over the years from analyzing plant foods for crude fiber (essentially what was left after extraction with a dilute acid or alkali solvent) to the more current methods that quantify remnants of plant cells, polysaccharides, lignin and other substances that resist digestion by the enzymes in the alimentary canal. This means that the analytical chemist must mimic the actions of mastication and digestion on a food in the laboratory and then measure what is left. Current research and labeling regulations recognize total dietary fiber, soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) based on AOAC methodology. Both SDF and IDF use an aqueous enzyme solution, with IDF being an insoluble fraction and SDF being precipitated by alcohol addition. The most common IDFs are cellulose, hemicellulose, lignin and resistant starch. The most common SDFs are pectins, beta-glucans and galactomannan gums. Polyfructans, such as inulin and fructooligosaccharides (FOS), and resistant maltodextrins do not fully precipitate in alcohol — other methodologies quantify their contribution to dietary fiber in a food. Defining fiberRecently, two scientific bodies proposed new definitions for fiber that differ in how they name and classify fiber. In 2001, the American Association of Cereal Chemists (AACC) Dietary Fiber Technical Committee adopted the following definition: “Dietary fiber is the edible parts of plants or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine. Dietary fiber includes polysaccharides, oligosaccharides, lignin, and associated plant substances. Dietary fibers promote beneficial physiological effects including laxation, and/or blood cholesterol attenuation and/or blood glucose attenuation.” In 2002, the Food and Nutrition Board (FNB) of the Institute of Medicine, Washington, D.C., developed the following definitions for fiber: “Dietary fiber consists of nondigestible carbohydrates and lignin that are intrinsic and intact in plants. Functional fiber consists of isolated, nondigestible carbohydrates that have beneficial physiological effects in humans. Total fiber is the sum of dietary fiber and functional fiber.” Based on current scientific data, the FNB established a requirement for total fiber for the first time, expressed as Adequate Intake (AI). This is based on grams per 1,000 kcal and the usual daily intake of energy to determine a grams-per-day value. Because it is based on energy consumption, the AI varies for different age groups and genders. For adult men, 19 to 50 years old, it is 38 grams per day, while for women in the same age group, the AI is only 25 grams per day. In the 51-plus age group, the AI goes down to 30 grams per day for men and 21 grams per day for women. Intended as the basis for new FDA labeling regulations, FNB developed the definitions of fiber and the AI for total fiber to help consumers and scientists identify fibers based on physiological functions and health benefits. Much of the research conducted on the value of high-fiber diets evaluates consumption from high-fiber-containing foods and not specific fibers. Additionally, research has identified properties such as being viscous and fermentable as beneficial, but these properties are not exclusively associated with the fiber’s solubility.
Comments
Similar ArticlesLatest ArticlesSubscribe toMobile Media SnapsText FOODPRODUCT to 41411 to receive this media snap on your smart phone Image GalleriesBuyer's Guidefeatured links |
SupplySide
Fiber in the Morning
Posted in
Articles,
Bakery,
Beverages,
Breakfast,
Cereal,
Fiber,
Grains,
Labeling,
Starches,
Healthy Foods,
Bakery / Cereal,
Grains / Pasta / Tuber,
Gums / Starches,
Fructooligosaccharides (FOS)
