Male and female rats fed the prebiotic-containing diet (Orafti Synergy1) also had a lower body weight, cholesterol and plasma triacylglycerolaemia compared to rats fed the control diet, researchers ETAP - Applied Ethology and the Universite Henri Poincare Nancy I report in the British Journal of Nutrition .
The study is reportedly the first time that increased survival rates of both male and female rats have been demonstrated after life-long supplementation with a prebiotic.
Repeating the study in humans may prove difficult however since lifelong compliance to the supplements may prove troublesome, but the news of benefits concerning body weight and blood lipid levels may have significant potential in the fight against obesity and obesity-related disorder.
The burgeoning prebiotic market has been largely created by three inulin producers, all based in Europe.
Other ingredient manufacturers are increasingly looking to promote the prebiotic effect of their products as evidence suggests that prebiotics could be even more useful than the probiotic bacteria that they feed.
Prebiotic ingredients, or those that boost the growth of beneficial probiotic bacteria in the gut, are worth about €90 million in the European marketplace but are forecast to reach €179.7 million by 2010, according to Frost & Sullivan.
Beneo-Orafti has been influential in building the science behind inulin and oligofructose, backing research into potential benefits for a variety of health conditions ranging from bones to colorectal cancer, from immunity to satiety and weight management.
Study details Lead researcher Pascale Prozan and co-workers took 60 female and 60 male three-month old rats and randomly assigned them to receive only the control diet, or the control diet supplemented with 10 per cent Synergy1 for 27 months.
The animals were analysed with respect to their sex.
Animals were weighed every two weeks and food intake was quantified on four successive days every four to six weeks.
The researchers note that throughout the entire study, males receiving the prebiotic lower body weight, cholesterol and plasma triacylglycerolaemia compared to the animals in the control group.
In terms of survival, at 18 months of age, all the animals in the prebiotic group were still alive, compared to 76 per cent in the control group.
After 24 months, 81 per cent of the rats in the prebiotic group were alive, compared to only 52 per cent of controls.
Similar results were observed in their female counterparts concerning the lower body weight, cholesterol and triacylglycerolaemia levels in animals fed the prebiotic-supplemented diet.
In terms of survival, at 18 months of age, all the animals in the prebiotic group were still alive, compared to 95 per cent in the control group.
After 24 months, 43 per cent of the rats in the prebiotic group were alive, compared to only 29 per cent of controls.
Mechanism of action The underlying mechanisms are still unknown, but suggestions centre on the beneficial alterations in the microbe populations in the large intestine, thereby improving digestive health which is vital to maintain overall health and well-being throughout life.
It has previously been reported that the microbial ecology of the intestinal tract changes with age, with decreases in levels of beneficial bifidobacteria and increases in potentially harmful clostridia, streptococci and enterobacteria.
Such changes may produce complications such as constipation, and increase the risk of developing diseases such as colitis or colon cancer.
Historical catalogue of benefits Considerable research has already focussed on the role of inulin and oligofructose in bone health and colorectal cancer, and the science is now expanding in ever-increasing circles to cover potential benefits for the immune system, weight management, and intestinal health.
Source: British Journal of Nutrition Published online ahead of print, 11 Apr 2008, doi: 10.1017/S0007114508975607, "Effects of lifelong intervention with an oligofructose-enriched inulin in rats on general health and lifespan" Authors: P. Rozan, A. Nejdi, S. Hidalgo, J.-F. Bisson, D. Desor, M. Messaoudi