Weight Perception and Diet Behavior of Japanese and Russian Adolescent Girls

Niigata City in Japan and Khabarovsk City in Russia signed a sister city agreement in 1965 and have been interacting with each other for a long time. We have been conducting comparative research on the elderly between the two cities, but there is no research on the young. Distorted perception of body weight and unnecessary dieting behavior in adolescent girls is considered a problem in both Japan and Russia. Therefore, the purpose of this study was to clarify the distortion of weight perception and diet behavior of adolescent girls in both the countries. In addition, it was decided to investigate the eating habits of people in both the countries. In total, 195 15-year-old girls from Niigata, Japan (October 2020) and 286 girls from Khabarovsk, Russia (February 2017) were surveyed. The questionnaire used was an excerpt from the World Health Organization survey on the health behavior of school-age children. The proportion of Japanese adolescent girls who perceived themselves as overweight (distorted body weight perception) was 60.5%, which was significantly higher than that of Russian adolescent girls at 30.1% (p < 0.001). In addition, the prevalence of weight loss behavior in Japan was 34.9% (n = 68), which was significantly higher than that in Russia with 27.3% (n = 78) (p < 0.001). Adolescent girls in Japan had more serious problems with weight perception, but had fewer problems with breakfast and vegetable intake habits than those in Russia. From a young age, perception of correct body shape and establishment of eating habits are important not only for current health but also for future health. We need to carefully educate adolescent girls that their body undergoes major changes through secondary sexual characteristics during adulthood.

Eating with Familiar Friends Decreases the Electrical Taste Threshold

Communal eating reportedly induces changes in food-related behaviors such as increased consumption and alleviation of indefinite complaints. Here, we examined the influence of intimacy with co-eaters on the palatability of the food and the physiological taste thresholds. The study was a single-blind crossover trial with 16 healthy women aged 18 - 19 years (two close friends × 8) as participants. We examined the effect of four preset conditions with regard to taste (condition 1 = tasting alone;condition 2 = tasting with a friend;condition 3 = tasting with three unfamiliar individuals;condition 4 = tasting with a friend and two unfamiliar individuals). Electrical taste thresholds were measured pre-and post-eating. The subjective evaluation of taste did not show any significant difference between the four conditions (p > 0.05). However, the electrical taste threshold significantly decreased when eating with close friends (p < 0.05). As a factor associated with the meal environment, co-eating with family or friends appears to influence tastiness;however, in the present study, it showed no effect on the perception of taste. Nevertheless, eating with friends significantly decreased the electrical taste threshold and enhanced the perception of taste. Decrease in the electrical taste threshold was observed only when eating with a close friend;it was not observed when eating with other people and showed no association with the total number of individuals co-eating.