Aug. 10, 2011 at 9:46 AM ET
If you’re trying to lose weight (and aren’t we all?), here’s a study to chew on:
The more your choppers mash up each bite of food, the less food you’re likely to eat at a meal, Chinese researchers reported recently in the American Journal of Clinical Nutrition.
In other words, Mom was right again, although her advice on this subject might have stemmed more from an exaggerated fear of choking than of having to buy clothes for you in the chubby department. The new study confirms: Don’t wolf down your food. Chew it, then chew it some more.
The latest research involved 16 lean and 14 obese young men. After a 12-hour fast, the volunteers came to the laboratory to eat a typical Chinese breakfast— pork pie, not Cocoa Puffs — while a video camera recorded how frequently they chewed each bite. All of the men were given the same portion and told they could ask for more.
The scientists theorized that the obese men would chew less per bite and, indeed, they were right. And while the size of their bites was similar to that of the lean men, the obese men ended up consuming more calories.
So the researchers, who were from Harbin Medical University, tried another experiment. They brought the men back to the lab and served up pork pie again for breakfast, as much as the men cared to eat. But one day they asked the men to chew each bite 15 times, while another day they asked them to chew 40 times.
Didn’t matter whether the men were obese or lean: They consumed about 12 percent fewer calories when they chewed each bite 40 times than when they chewed 15 times, and they had lower levels of ghrelin, the so-called hunger hormone produced in the stomach.
“Chewing less is a risk factor for obesity,” the scientists conclude, perhaps because increased chewing releases nutrients from food more efficiently. Encouraging people to chew more, they write, could be a valuable tool--along with diet and exercise--for helping people lose weight.
I wondered if that might be biting off more than many people could chew, so I asked Mauro Farella of New Zealand’s University of Otago how hard it would be to get folks to masticate more.
Farella was the senior author on a chewing paper posted Aug. 1 by the Journal of Dental Research. He and his coauthors had theorized that people chew at their own consistent pace, part of their unique “fingerprint of masticatory behavior.” His study didn’t find a link between the pace at which people chewed and how thoroughly they chewed.
“I have no idea about whether it would be possible to teach an individual to slow down or up the chewing pace or to change the duration of chewing before swallowing,” Farella says. In principle, though, he says it might be possible to get people to chew each bite more, because, as Mom knows, we at least have partial control over it.