Clinical trials show benefit of increasing fibre intake
Present day interest in the importance of fibre stems from the middle of the 19th Century when the Victorians were preoccupied with their bowel movements. At this time, physicians declaimed the virtues of bran. But over the centuries each generation of medical scientists have had differing views. This was until the early 1900's when fibre was eventually singled out as the principal component of bran responsible for its colonic effect1.
The importance of fibre today is well documented, although the intake of dietary fibre among people in Western countries remains low2. Various clinical trials conducted within the last decade have further shown the positive effect of a high fibre diet on various conditions and illnesses.
One such trial, the results of which were published in the New England Journal of Medicine2, studied the effect of an increased intake of dietary fibre on glycemic control in patients with type 2 diabetes. This randomized crossover study saw a group of diabetic patients being divided into two sub groups to follow very specific diets for six weeks: One diet contained moderate amounts of fibre, while the other eating plan contained fibre above the recommended level. Both diets were prepared in a research kitchen and contained the same macronutrient and energy content. The results of this study shows that a high intake of fibre, particularly of the soluble type, improved glycemic control, decreased hyperinsulinemia and lowers lipid concentrations2. Patients who are concerned about glycemic control are advised to speak to their doctor.
Fibre is an important factor thought to reduce the risk of colorectal cancer. In May 2003, respected medical journal The Lancet3 published the results of a study that examined the association between dietary fibre intake and the incidence of colorectal cancer. Over a six year period more than 500 000 individuals aged 25 - 70 years from 10 European countries completed a questionnaire and were followed up for cancer incidence. The study found that in populations with low average intake of dietary fibre, an approximate doubling of total fibre intake from foods could help reduce the risk of colorectal cancer by 40%3.
A year later, the results of another extensive study were published4, this time a pooled analysis was conducted investigating dietary fibre and its subtypes and the risk of coronary heart disease. By examining the original data from 10 prospective American and European studies, and conducting over six to 10 years of follow ups, it was established that total dietary fibre (from cereals and fruit) was associated with a decrease in risk of all coronary events and a decrease in risk of coronary death4. Adjustments for demographics, body mass index and lifestyle factors was also taken into account in this study, and the result that dietary fibre is inversely associated with risk of cardiovascular disease was applicable for both men and women4.
Fibre supplementation and weight management has also been a subject of interest and controversy. In fact, when critically studied, only a few controlled studies have shown a modest weight loss induced by soluble fibre supplementation. To investigate the practical reliability of this hypothesis, a random, double-blind, placebo-controlled study was conducted amongst moderately overweight females in Norway. While after 24 weeks both groups who had followed a reduced energy diet had considerably lower blood pressure, the group taking fibre supplementation lost an average of 8kg versus 5.8kg in the placebo group. While the explanation for the more rapidly achieved weight loss in the fibre group is not clear, several possible modes of action have been proposed, including lower energy intake and enhanced satiety5.
Few people achieve optimum fibre intake on a daily basis, which has made fibre supplementation an important option for many health conscious consumers globally. One such supplement is Benefiber, a taste-free, all-natural powder, which has been studied intensively for use in human nutrition, and is grit-free and non thickening6. A consumption of 20-30g per day is considered physiological, while 60g a day over a week did not cause any toxicity problems7. Supplementation with Benefiber has also been shown to help reduce constipation and the use of laxative agents, and also assists in increasing beneficial bacteria to help promote normal bowel function8.
Furthermore, in a human clinical trial conducted in 2002, the results of which were published in the Digestive Diseases and Sciences journal in the United States, Benefiber was found to have greater success than wheat bran for improving abdominal pain and bowel habits in sufferers of irritable bowel syndrome (IBS)9. Other studies found that Benefiber did not interfere with normal intestinal absorption of carbohydrate, fat or protein amongst the patient population being observed, and was found to effectively increase the frequency of bowel movements and increased frequency of beneficial bacteria in those women in the respective studies who suffering from constipation9.
The only active ingredient in Benefiber is Wheat Dextrin, a natural soluble fibre. The recommended daily intake of Benefiber for adults is 2 teaspoons three times daily (for an additional nine grams of dietary fibre per day)10.
References:
1. Cummings JH. The Effect of Dietary Fiber on Fecal Weight and Composition. CRC Handbook of Dietary Fiber in Human Nutrition, 2nd Edition.
2. Chandalia M, Abhimanyu G, Lutjohann D et al. Beneficial Effects of High Dietary Fiber intake in Patients with Type 2 Diabetes Mellitus. The New England Journal of Medicine. May 11, 2000. 1392 - 1397.
3. Bingham SA, Day NE, Luben R et al. Dietary fibre in food and protection against colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC): an observational study. The Lancet. Vol 361. May 3, 2003. 1496 - 1501.
4. Pereira MA, O'Reilly E, Augustsson K et al. Dietary Fiber and Risk of Coronary Heart Disease - A Pooled Analysis of Cohort Studies. Arch Intern Med / Vol 164, Feb 23, 2004. 370 - 376
5. Birketvedt GS, Aaseth J, Florholmen JR et al. Long Term Effect of Fibre Supplement and Reduced Energy Intake on Body Weight and Blood Lipids in Overweight Subjects. Acta Medica. 2000; 43 (3): 129-132
6. About Benefiber (http://www.benefiber.com/fiberHealth/index.shtml?aboutBenefiber)
7. Benefiber (http://www.novartismedicalnutrition.com/newsletter/pdfs/benefiber.pdf)
8. Patrick PG, Gohman SM, Marx SC. et al. Effect of supplements of partially hydrolyzed guar gum on the occurrence of constipation and use of laxative agents. Journal of the American Dietetic Association. August 1998 Volume98 Number 8.
9. Benefiber Human Clinical Studies (http://www.novartisnutrition.com/pdfs/us/moreproductinfo/benefiber_study.pdf)
10. Benefiber FAQ's (http://www.benefiber.com/fiberHealth/index.shtml?faqs)
Editorial contact
Leigh Hopewell at The Write Agency
011 467 5368 / 083 264 6563