Prebiotics beyond digestion
August 28, 2012
by Jeff Gelski
Two studies presented this year examined satiety effects of prebiotic fiber ingredients, but their results differed. The World Health Organization has defined prebiotics as non-digestible food ingredients that may bene-ficially affect the host by selectively stimulating the growth and/or the activity of a limited number of bacteria in the colon. These healthy bacteria also may be known as probiotics such as lactobacillus and bifidobacteria.
While prebiotics and probiotics are known for their digestive effects, research has focused on other potential prebiotic fiber benefits such as satiety, calcium absorption and sugar reduction capabilities.
The European Journal of Nutrition this year published a study on polydextrose, a prebiotic fiber, that was performed at the Functional Food Centre of Oxford Brookes University in the United Kingdom. The study recorded a 10% reduction in energy intake at a monitored lunch when people ate polydextrose 60 minutes before the lunch.
DuPont Nutrition & Health offers Litesse polydextrose, which is 1 calorie per gram compared to sugar at 4 calories per gram.
“Successful weight management is ultimately about balancing the energy we consume as food with the energy that we expand through exercise,” said Michael Bond, health platform leader for DuPont Nutrition & Health. “Consuming less at mealtimes and selecting less energy dense foods can help individuals to achieve this balance.
“As Litesse contains 75% less calories than sugar, increases satiety and helps to reduce the desire to eat, it is an ideal ingredient for reducing sugars and calories in products focused on weight management.”
Research at the University of Minnesota in Minneapolis focused on three forms of prebiotic fiber (oligofructose, inulin and soluble corn fiber) as well as resistant starch. Results of the study appeared on-line July 6 in the Journal of the Academy of Nutrition and Dietetics.
The study tested the satiating properties of the four fibers and involved 22 women. The women ate a dinner bar containing one fiber at night and the same dinner bar the next morning. A bar with no fiber served as the control.
Repeated ratings of feelings related to hunger and fullness at a lunch meal were the main measures. No differences were found in subjective satiety during the morning or food intake at lunch or over 24 hours.
Joanne Slavin, a professor in the Department of Food Science and Nutrition at the University of Minnesota who was involved in the study, said she acknowledged prebiotic fiber ingredients may have other benefits.
“There are no regulatory standards for prebiotics,” she said. “Increased levels of ‘good’ bacteria are thought to have advantages on immunity. Also, any fiber that is fermented and decreases the pH of the colon may increase calcium absorption.”
The University of Minnesota will continue to study fiber.
“Most of our current satiety studies are with whole foods and bran fibers as they have more data that they impact satiety,” Dr. Slavin said. “We are working on fiber blends and changes in gut microflora.”
Suppliers of prebiotic fiber ingredients promote such benefits as calcium absorption, sugar reduction abilities and weight management.
Beneo offers Orafti Synergy1, an oligofructose-enriched inulin. Research at the Children’s Nutrition Research Center at the Baylor College of Medicine in Houston showed the ingredient increases calcium uptake to promote bone health.
Sensus, Lawrenceville, N.J., offers Frutalose SF75, an inulin ingredient that is 75% dietary fiber and 65% as sweet as sugar, and promotes it as a low-calorie sweetener that has been shown to support weight management, provide humectancy, enhance satiety and mask artificial sweeteners.
Cargill, Minneapolis, offers Oliggo-Fiber inulin and promotes its benefits in digestive health, bone health and weight management.
Ingredion, Westchester, Ill., offers prebiotic fiber ingredients in fructooligosaccharides (FOS) and galactooligosaccharides (GOS). Purimune, a prebiotic fiber ingredient derived from lactose, contains a minimum of 90% GOS, according to Ingredion. It passes intact through the mouth, stomach and small intestine to the colon, where it is fermented by beneficial bacteria into short-chain fatty acids (S.C.F.A.). The S.C.F.A. promote digestive and immune health as well as enhance mineral absorption.