Yes, Eating Slowly Does Mean Eating Less

For years, Dr. Kathleen Melanson of the
University of Rhode Island had heard that eating more slowly would translate into eating less, but when Melanson attempted to verify that advice with scientific data, she found none. So the nutritional  researcher created her own. The Scientific American reports that Melanson and colleagues had 30 young women eat a meal of
ditalini with tomato and vegetable sauce, topped with Parmesan
cheese, under two different conditions. Before each meal, the
women had eaten a standard 400-calorie breakfast, and then
fasted for four hours. At one visit to the lab, study participants were given a
large spoon and told not to pause between bites and to eat as
quickly as possible. At the other, participants ate with a
small spoon, which they put down after each bite, and were told
to take small bites and chew each bite 15 to 20 times. Sciam reports that when eating quickly, the women took in an average of 646
calories in nine minutes. But when they slowed down, they
consumed 579 calories in 29 minutes. Melanson points out that
someone who ate three leisurely meals might consume 210 fewer
calories a day than someone who wolfed those meals down.