Why do millions of people repeatedly fail to stick to their diets despite longing for slim, good-looking bodies?

Mostly because they can't withstand the hunger, according to a 2007 survey of 693 people conducted by Asahi Breweries Ltd.

Asahi now claims to have developed a secret protein powder that could put a halt to diet futility.

The brewery claims that a protein it has extracted from soybeans stays in the stomach longer, significantly helping to reduce hunger pangs and thus the amount of food people eat.

"Using (this protein) has the potential to help people continue dieting in a healthy manner," the company said in a statement Monday.

The firm is preparing to release the results of its scientific study on the protein Wednesday at a three-day academic session of the Japan Society for Biosicence, Biotechnology and Agrochemistry.

In an experiment, 5 grams of food, including a gram of the new protein, was fed to rats. At a feeding 10 hours later, the same rats ate 15 percent less food than those that were not given the protein, the firm said.

In a separate experiment, the company colored the protein to see how long it stays in rats' stomachs. An hour after it was consumed, more than 50 percent of the new soybean protein remained, compared with around 20 percent of other proteins, the firm said.

Asahi Breweries has already added the protein to some of its products, and the more satisfying foods should hit stores soon, company spokesman Keiji Maejima said.

"The protein has been extracted from (soybeans), which is quite familiar to Japanese, so they can keep eating it without worry," the company said.

Hunger was listed as the main reason for giving up on dieting by 56 percent of the people Asahi surveyed.