Reduced masticatory function in non-elderly obese Japanese adults

Abnormal eating behaviors such as compulsive overeating, eating fast, chewing less, palatable soft food preferences and avoiding hard food are often observed in obese individuals, and these behaviors may affect their masticatory function, but little information of masticatory function in obese subjects are available at present. The present study investigated masticatory function in non-elderly obese Japanese adults and explored the relationships between obesity and masticatory function.

Seventy-five obese subjects (BMI ≥ 25; male: 34, female: 41) and 98 subjects with normal weight (BMI 18.5-25; male: 63, female: 35) aged 25-40 years old were enrolled in the present study. The status of masticatory function was determined using a chewing gum mixing method, a direct method of examining masticatory function, and the numbers of present teeth, untreated decayed teeth, missing teeth, and filled teeth were also examined.

Masticatory function was significantly lower in the obese subjects both in male and female, whereas the numbers of present teeth, decayed teeth, missing teeth and filled teeth did not differ significantly between the obese subjects and the controls both in male and female. Multiple regression analysis revealed a significant correlation between obesity and reduced masticatory function after adjustment for gender, age, and numbers of decayed teeth, missing teeth, and filled teeth.

Significantly reduced masticatory function was found in male and female non-elderly obese adults based on direct measurement of masticatory function. Multiple regression analysis suggested that obesity might induce reduced masticatory function.