Factors associated with the masticatory behavior of children assessed by the number of chews for a test meal of usual school lunch menu.

Aim: To investigate the characteristics of children’s masticatory behavior and the associated factors by measuring the number of chews and time taken for eating the test meal. Seting and subject: A cross-sectional observation on 61 children (5–6 years old) from two kindergartens. Methods: The number of chews [= NC] and time taken for eating the test meal [= MT (minutes)] of a usual school lunch menu were measured by a portable chewing counter. The occlusal force was also assessed by a dental prescale, and a questionnaire was given to their guardians on their daily masticatory behavior. We formulated the “timeadjusted number of chews” [= adjusted-NC] to consider the influence of MT by the residue method and to provide a new indicator for inter-individual variation in masticatory behavior. Results: Adjusted-NC was significantly associated with the degree of obesity (r = –0.28; p = 0.041), while MT was negatively associated with the body height (r = –0.31; p = 0.018), body weight (r = –0.30; p = 0.026) and degree of obesity (r = –0.27; p = 0.047). A multiple-regression analysis (stepwise method) showed a positive association between the guardians’ behavior of “choosing ingredients for meals and snacks with consideration to facilitate their child chewing wel” and adjusted-NC. The guardians’ judgment on children “frequently keeping food in their mouth without soon swalowing” was positively associated with MT (r = 0.35; p = 0.010), and “eating without chewing wel” was negatively associated with MT (r = –0.33; p = 0.011). No associations with other factors were apparent for the occlusal force. Conclusions: Obese children were likely to eat faster and chew less, and that children with a smal body frame were likely to spend more time with larger NC for the test meal. The guardians’ atitude to food choice was associated with the measured children’s masticatory behavior. The figure for adjusted-NC measured with the test meal, which was associated with obesity and other factors, can be utilized for relevant researches, and can provide a piece of evidence to improve the practices in nutrition education targeting the children’s masticatory behavior. Jpn. J. Nutr. Diet., 68 (4) 253~262 (2010)