Wheat dextrin and psyllium husk are both water soluble dietary fibres. Soluble fibres are an essential food component that regulates the gastrointestinal (GI) tract and moderates the absorption of glucose (sugar). The typical American diet is low on fibre, according to the American Dietetic Association (ADA). One way to raise the fibre level in a diet is to add wheat dextrin or psyllium to your daily food intake.
Wheat dextrin is a fibre made from wheat starch. Dextrins are defined by the U.S. Food and Drug Administration (FDA) as a food ingredient manufactured from the starch of plant foods, including corn, potato or wheat. Psyllium comes from the seed husks of a plant identified as plantago ovata, which grows in Pakistan and India. Its use as an herbal remedy to relieve GI problems dates back centuries.
Psyllium is one of the richest sources of soluble fibre available with approximately 13 grams of fibre per tablespoon. It swells when mixed with water, creating a thick, gelatinous substance. This is what gives it both a laxative effect and its colon cleansing power. Wheat dextrin is also very high in fibre, at approximately 8 grams per tablespoon. Wheat dextrin does not have as much of a thickening effect in liquids. Oat bran, a good source of fibre, has about 1 gram per tablespoon.
You won't find wheat dextrin on the store shelf. It is sold under brand names, like Benefiber powder which lists wheat dextrin on the list of ingredients. Psyllium is sold as a herbal supplement in health food stores. It can also be an ingredient in brand names. For example, psyllium is a major ingredient in Metamucil.
Consuming wheat dextrin can produce less gas and bloating than psyllium, and it doesn't thicken so quickly in liquids. Psyllium may cause bloating or gas, especially the first week or two of regular use. However, gas and bloating do occur with either fibre in some sensitive individuals.
Wheat dextrin is considered "gluten-free" by the FDA's definition of less than 20 parts per million (ppm). Wheat dextrin is in fact a by-product of extracting the gluten from wheat but complete extraction is not guaranteed. Individuals who are gluten-intolerant should avoid wheat dextrin. Since psyllium is not a wheat product at all, it is safer for the gluten-intolerant.
"The Journal of Clinical Gastroenterology" published an analysis of available reports that show soluble fibre can be a help in controlling irritable bowel syndrome (IBS) symptoms. Because of the greater chance of gas and bloating with psyllium, wheat dextrin may be the better choice for IBS sufferers prone to these symptoms.
In more than 60 controlled trials on the use of soluble fibres, regular intake of soluble fibre for persons with Type II diabetes is safe, well tolerated, and improves glycemic control. Diabetics taking large doses of soluble fibres should check with their physician for changes in medication requirements. Soluble fibres slow the rate of digestion and glucose absorption, which may decrease the need for diabetes medications.
In 1997, the FDA allowed foods containing psyllium to make the health claim on reducing risk of heart disease. Studies reviewed in "The American Journal of Clinical Nutrition" since then show that soluble fibres in general lower total blood cholesterol and LDL cholesterol about 5 to 8 per cent, which is about half as well as many cholesterol-lowering drugs (cholestyramine, colestipol and probucol). As for wheat dextrin, it is being added to many foods to make them more fibre rich--cereals and breakfast bars, cookies and more.
Both wheat dextrin and psyllium are water soluble fibres. They will pull water from your body, so it is essential to stay well hydrated when you consume them. You must drink adequate water when taking soluble fibres. Additionally, psyllium can be difficult to swallow, due to its thick consistency, and should be avoided by those who have difficulty swallowing.