Anti-Appetite Molecule In Fiber Could Combat Obesity

Scientists identified an anti-appetite molecule called acetate in fiber that could possibly help combat obesity; the study describes in the journal Nature Communications.

Acetate is naturally released when we digest fiber in the gut, and once released, the molecule is transported to the brain where it produces a signal to tell us to stop eating.

It is widely known that a diet high in fiber is beneficial, but this study confirms on a molecular level that increasing dietary fiber can actually suppress appetite.

"The average diet in Europe today contains about 15 g of fiber per day," lead author of the study Professor Gary Frost, from the Department of Medicine at Imperial College London said in a statement. "In stone-age times we ate about 100g per day but now we favor low-fiber ready-made meals over vegetables, pulses and other sources of fiber. Our research has shown that the release of acetate is central to how fiber suppresses our appetite and this could help scientists to tackle overeating."

Researchers tracked the pathway of acetate from the colon to the brain and identified some of the mechanisms that enable it to influence appetite.

Using a mouse model, researchers demonstrated that mice fed on a high fat diet with added inulin - a form of dietary fiber that comes from chicory and sugar beets and is also added to cereal bars - ate less and gained less weight than mice fed on a high fat diet with no inulin. Also, the same mice with lots of dietary inulin had increased acetate levels as well.

Positron emission tomography scans revealed that acetate ends up in the hypothalamus region of the brain after it travels through the body, the region that controls hunger.

"It's exciting that we have started to really understand what lies behind fiber's natural ability to suppress our appetite and identified acetate as essential to the process," co-author Professor Jimmy Bell from the MRC Clinical Sciences Centre commented. "In the context of the growing rates of obesity in western countries, the findings of the research could inform potential methods to prevent weight gain."