Effects of a Six-month Program of Chewing Each Bite of Food 30 Times on the Body among Adults

Abstract

To investigate the effects of chewing food 30 times per bite on meal composition, body metrics, grip strength, satiety, and other factors, a group who ate each meal by chewing their food 30 times per bite before swallowing (the chewing group) and a group who ate as normal (the control group) were compared over the course of six months.

A meal survey and measurements of body metrics and bone density were conducted at the start of the experiment, after three months, and after six months. Grip strength was measured at the start of the experiment and after six months. At the beginning of the study, both groups ate the same boxed meal (Hotto Motto brand, energy: 748 kcal), and the number of times food was chewed and duration of eating were measured. Level of hunger prior to the meal and satiety after the meal were also measured using visual analog scales (VAS). After six months, both groups were served the same boxed meal again and the same measurements were taken. Additionally, masticatory force was measured using XYLITOL™ “Chew Strength Checking Gum” (a color-changing chewing gum used for assessing masticatory performance) (LOTTE Co., Ltd.) at the beginning of the study and after six months. All measurement results were compared between the chewing group and controls.

When the boxed meal was served at the end of six months, the chewing group showed a significant increase in the number of times food was chewed compared to the beginning of the experiment (p<0.05). The chewing group also exhibited increases in masticatory force (p<0.05), and in skeletal muscle mass and grip strength (p<0.001).Furthermore, the increased number of times food was chewed resulted in increased diet-induced thermogenesis, and decreases in body weight (p<0.05) and body fat percentage (p<0.001). The chewing group also showed improved grip strength, which is said to reflect overall muscle strength. Based on these results, chewing each bite 30 times was shown to have a positive impact on physical health. Encouraging more chewing in nutritional guidance may therefore contribute to lifelong maintenance and improvement of health.