Chew More and Eat 12 Percent Less

A new study finds that people who chew their food more take in fewer calories, which may help them control their weight. 

Chewing food 40 times instead of a typical 15 times caused study participants to eat nearly 12 percent fewer calories, according to results of a published study.

Jie Li and colleagues from Harbin Medical University in China gave a typical breakfast to 14 obese young men and 16 young men of normal weight to see if there were differences in how they chewed their food. The researchers also looked to see whether chewing more would lead subjects to eat less and would affect levels of blood sugar or certain hormones that regulate appetite.

Previous research has explored the connection between obesity and chewing, with mixed results. Several studies have found eating faster and chewing less are associated with obesity, while others have found no such link.

Co-author Shuran Wang noted that, in the current study, the team found a connection between the amount of chewing and levels of several hormones that “tell the brain when to begin to eat and when to stop eating,” More chewing was associated with lower blood levels of ghrelin, a hormone that stimulates appetite, as well as higher levels of CCK, a hormone believed to reduce appetite. These hormones may “represent useful targets for future obesity therapies,” Wang stated, since regulating their levels may help people control their appetite.

The authors found no difference between the size of bites taken by obese or normal-weight men, and no link between chewing duration and blood sugar or insulin levels in any of the men.

Since the study was small and only included young men, it does not necessarily predict how extended chewing will affect the calorie intake of other people, the authors noted.

The 12 percent reduction in calories eaten by the group who chewed their food 40 times in the study could potentially translate into significant weight loss, however.

If the average person cut their calorie intake by 12 percent, they would lose nearly 25 pounds in one year. Despite the study’s limitations, the authors say the relationship between eating behaviors and obesity is worth studying further, to help slow a growing health problem worldwide.

American Journal of Clinical Nutrition, online July 20, 2011.