London, Dec 11 (IANS): British scientists have found that an ingredient, when added to daily food, can make people feel full and prevent weight gain.

In tests carried out on humans, researchers at Imperial College London and University of Glasgow found the ingredient contains propionate which stimulates the gut to release hormones which act on the brain to reduce hunger.

Propionate is produced naturally when dietary fibre is fermented by microbes in the gut.

But the new ingredient called inulin-propionate ester (IPE) provides much larger quantities of propionate than people can acquire with a normal diet.

"Supplementing one's diet with the ingredient prevents weight gain in overweight people. You need to eat it regularly to have an effect," claimed professor Gary Frost from the department of medicine at Imperial College London.

During the study, the first 20 volunteers were given either IPE or inulin, a dietary fibre and were allowed to eat as much as they liked from a buffet.

Those given IPE ate 14 percent less on average and had higher concentrations of appetite-reducing hormones in their blood.

Next, 60 overweight volunteers took part in a 24-week study in which half were given IPE as a powder to add to their food and half given inulin.

One out of 25 volunteers given IPE who completed the study, gained more than three percent of their body weight, compared with six out of 24 given inulin.

After 24 weeks, the IPE group also had less fat in their abdomens and livers compared with the inulin group.

"Molecules like propionate stimulate the release of gut hormones that control appetite, but you need to eat huge amounts of fibre to achieve a strong effect. We wanted to find a more efficient way to deliver propionate to the gut," said Frost.

The researchers are exploring what kind of foods could be added but something like bread or fruit smoothies might work well, concluded the paper that appeared in the journal Gut.