Seaweed: the new diet food?

Speaking at the Vitafoods show in Geneva in May, Jeff Pearson, professor of molecular physiology at the University of Newcastle, told delegates that initial experiments had indicated that alginate, when added to food as a dietary fibre, could significantly reduce the amount of fat absorption in the body.

"We have just been given approval to go ahead with experiments in humans. We're hoping that this next step will show whether the effects that have been modelled in the lab can be reproduced in humans," said Pearson.

"It's not enough just to prove the effect in lab, as the industry is well aware, there are strict European Food Safety Authority criteria that it must satisfy in order to make health claims on products; so we are hoping that by conducting these experiments in humans we will be one step closer to discovering an effective anti-obesity food ingredient."

So far, the team of scientists, led by Pearson and Dr Iain Brownlee, found that alginate a natural fibre found in sea kelp stops the digestion of fat by 75%. Using an artificial gut, they tested the effectiveness of more than 60 different natural fibres by measuring the amount of fat that was digested and absorbed with each treatment.

The university research team claimed that the alginate was more effective "than most anti-obesity treatments currently available over the counter".

Alginates are commonly used at a very low level in the food industry as thickeners and stabilisers. When added to bread, the team of researchers found that, in blind taste tests, some people actually preferred it to a standard white loaf because the added fibre enhanced mouthfeel.

It also extended the shelf-life of bread, claimed Pearson. "We're hoping that it will also be an effective ingredient in other bakery products, such as biscuits, or in dairy products such as yogurts," he added.

The research is part of a three year project being funded by the Biotechnology and Biological Sciences Research Council.