Kiwi researchers experimenting with a bitter plant extract have developed a potential appetite suppressant, they have told an international obesity conference.

They have not named the plant but presented test results to the European Obesity Summit in Sweden, showing that taking capsules containing the plant extract, Amarasate, was associated with subsequently consuming fewer kilojoules.

The experiment was done in 19 men of normal weight. For three treatment days, after fasting overnight, they ate a standardised breakfast and took capsules at 11am.

Participants given active capsules consumed on average 911 kilojoules less for lunch and 944kJ less snack food.


In 2008/09, the New Zealand Adults Nutrition Survey found the median daily energy intake was 10,380kJ for men and 7448kJ for women.

Amarasate, described as a "bitter brake", has been developed by researchers from Plant & Food Research and Auckland University and they have a registered a trademark for the product.

"Activation of the bitter brake mechanism by a bitter plant extract can stimulate the release of gut peptide hormones involved in appetite regulation and suppress subsequent feeding behaviour in healthy men," they say.

Auckland City Hospital diabetes and obesity expert, Dr Robyn Toomath, said such research was important. The only effective solution for obesity currently is bariatric surgery, she said, but it would be preferable to create a healthier food environment.

"Many years ago I thought that obesity would be treated ... with a range of medications targeting different aspects of the problem, but sadly they have all proved to be failures or to have unacceptable side effects.

"Even if [this drug] and other drugs did work, we can't have two-thirds of the population [the adult overweight/obesity rate] medicated for what is essentially an environmental problem."

Food control

• Amarasate is an experimental appetite suppressant.


• 19 men of normal weight took active capsules or placebos.

• Amarasate was associated with eating less in the following hours.