Eat Soup, Lose Weight
(science weighs in)

J. Raloof reports in the April 24, 1999, issue of Science News on new research that supports the common sense belief that filling up on healthy soup can decrease appetites and increase weight loss.

A study by Barbara J. Rolls and Elizabeth A. Bell of Pennsylvania State University is based on the fact that, for satiety purposes, the body's natural sensors don't register how many calories a person has just eaten. Thus, an artful cook can discourage overeating by making each calorie more filling. How? With water. In soup.

The study was conducted in 3 parts, feeding 24 young women a 270-calorie appetizer of chicken-rice casserole--first, by itself; second, with a 10-ounce glass of water; and last, by dumping the glass of water into the casserole (back in the kitchen) and serving it up as chicken-rice soup. After each round, experimenters measured how much lunch the women ate afterwards. Hands down victory for soup: instead of following up with a 300-calorie lunch, as with the casserole or casserole/glass of water, they daintily pushed their plates away after 200 calories. That's a one-third reduction! Nor did they get hungry earlier or eat a bigger dinner later. It reinforces the idea that food and drink after hunger and satiety through different mechanisms and only when the water is processed as a "food" does it add measurably to satiety.

I would only add that while you should not expect dramatic weight loss if you only eat cream soups larded with butter and eggs, you could argue that such a soup might more effectively keep you from scarfing down the chocolate mousse than if you'd started with an omelet.