Gas-Filled Liquids Curb Appetite

May 16, 2008 -- Fear you'll have to forgo your mocha frappuccino fix to squeeze into summer's skimpy fashions? No problem, just order your drink with an extra shot of, um, gas.

Scientists say a liquid meal made with tiny gas bubbles can fill up your tank and give you more mileage between meals. It might sound like an infomercial, but study data being presented this week at the 16th European Congress on Obesity in Geneva, Switzerland, shows that a new high-tech diet liquid meal infused with gas reduces appetite for hours.

Previous studies have suggested that increasing food volume with water or air can increase the feeling of fullness and decrease subsequent food intake, according to background information in the study abstract.

Researchers with the Unilever Food & Health Research Institute examined the effects of gas-filled liquid foods on the appetites of 24 overweight adults about 42 years old. Unilever makes many products, including Slim-Fast.

The study participants received a gas-filled liquid meal or a standard liquid shake, either as a single large serving (1,000 milliliters for the gas-filled liquid, 325 milliliters for the standard liquid), or as two half-servings given two hours apart. The total calorie count from the drinks was the same. Participants reported feelings of hunger and fullness for four hours after drinking the shakes.

The experiment showed that both the full- and half-size gas-filled liquids significantly reduced appetite ratings when compared to the standard liquid meals.

But one might wonder: Could a belly full of gas lead to a big bellyache? Researchers noted "increased reports of gastrointestinal complaints" among those who received the large gas-filled liquid meals.