A daily prebiotic supplement helps to increase bone mineral density, shows new research funded by inulin maker Orafti.
The firm's RaftiloseSynergy1, an enriched inulin powder, increased calcium retention and accretion in bones by 15 per cent after a year, reported the firm today.
The findings will be a major boost to the ingredient as food makers seek to offer products to consumers that are increasingly aware of the threat of osteoporosis.
The bone-wasting disease now affects an estimated 75 million people in Europe, USA and Japan, according to the International Osteoporosis Foundation.
Many young girls get as little as 10 per cent of the calcium they need each day, often a result of avoiding dairy products. But by increasing the mineral density of bone in early life and retaining it, osteoporosis risk can be significantly reduced.
Previous studies have shown that taking 8g of Orafti's oligofructose-enriched inulin increased the calcium absorbed from the diet by up to 20 per cent.
The new study, carried out by Professor S.Abrams from the Baylor College of Medicine and the Texas Children's Hospital in Houston, shows a significant 15 per cent increase of calcium retention and accretion within the bones of the 100 girls and boys, aged nine to 13, after one year of supplementation.
Dr Anne Franck, vice president of science and technology at Orafti, said: "If effects are not long-term they have little clinical benefit. The Abrams research is physiologically significant as it provides an insight into the longer-term effect of RaftiloseSynergy1 and demonstrates that it can be highly beneficial in increasing bone mineral density."
She added that standard inulin and oligofructose also improve mineral absorption, but only at higher dosages, so they are not suitable for related health claims.
"With the patented RaftiloseSynergy1, calcium absorption and bone density claims are possible with only 8g/day," said Dr Franck.
For the study, half of the sample was provided with 8g of RaftiloseSynergy1 to consume with breakfast each day for a year, while the other half was provided with a placebo. Prior to the start of the research, all participants underwent measurements of calcium absorption and retention, via blood and urine samples, and bone mineral content and density, via X-ray body scans. These tests were repeated after two months and at the end of the year-long study.
Regular checks were also made on the participants' average daily diet in order to ensure that no significant changes in calcium intake occurred. Calcium intake was maintained throughout the study at usual levels around 900 mg/day.
The prebiotic is thought to work by changing the flora in the colon, with the more slowly fermented inulin acting as a selective 'fuel' for this modified flora, which is kept metabolically active further in the gut.
This selective fermentation pattern results in the production of short chain fatty acids, which decrease the pH within the colon, improving the solubility of the calcium present. The calcium is then better absorbed into the body.