We examined the effectiveness of two types of nutrition education, one based only on the theory of health behavior (HB), and the other (HB+GI) on the theory of health behavior (HB) combined with the glycemic index (GI). The study subjects were 41 undergraduate students divided into two groups: 20 students for the HB nutrition education, and 21 for the HB+GI nutrition education. Each group of research subjects was educated by the respective method for 5 months. A comparison before and after nutrition education showed improved awareness and behavior of the students towards their diet. However, their awareness of good nutrition was improved much more than their behavior toward it, suggesting the further benefits of long-term education in order to improve eating habits. A comparison between the HB and HB+GI groups showed differences in the degree of change in the subjects' behavior; for instance, we found that the food intake by the HB+GI group became more nutritionally proper. These results show that nutrition education based on the theory of health behavior resulted in a more nutritionally suitable food intake when combined with GI considerations. We propose that nutrition education incorporating the perspective of GI can motivate students toward achieving a nutritionally proper food intake.
The eating habits, psychological features, and nutritional conditions of 1, 219 female university students were surveyed in July 2002 for early detection of eating disorders and early treatment. The relationships among these factors were also investigated. The results of the eating habit questionnaire enabled the students to be classified into four groups: one healthy group with no eating disorders (63%) and three groups with a tendency toward eating disorders (37% of the total), comprising those with anorexia nervosa (AN, 1.5%), those with bulimia nervosa (BN, 31.1%), and those with both anorexia and bulimia (AN+BN, 4.4%). A nutritional assessment of 122 of the 1, 219 subjects indicated those tending toward a nutritional disorder accounted for 41.8%, including those with an eating disorder (ED, 2.5%) and undernourished persons (LN, 39.3%). Those persons tending towards an eating disorder who responded to a questionnaire regarding psychological features indicated a positive correlation between somato-type negativism and good-child thinking, binge eating and a desire for maturation, a desire for thinness and self-negation, and a desire for thinness and perfectionism. There was no significant difference in the self-expression item among the four groups (healthy, AN, BN and AN+BN); this seems to be a characteristic of female university students. The energy, fat and cholesterol intakes of the ED subjects were all lower, whereas the intakes of iron and dietary fiber were higher than those of the healthy subjects.
A questionnaire survey was conducted on female college students to examine how they check nutrition labels and use the information for adjusting their intake of four kinds of food: confectionery, soft drinks, milk products, and mayonnaise. The association between their label use and such characteristics as body image, nutrition knowledge, attitude toward nutrition labels was evaluated by a chi-square test, multinomial logistic regression analysis and multiple logistic regression analysis. The subjects were classified into three groups: those who don't read nutrition labels, those who do read them, and those who read and act on them. These groups respectively constituted 24.8%, 28.5% and 46.7% of the total. The multinomial and multiple logistic regression analyses identified body image as the independent factor associated with the transition from non-readers to readers of nutrition labels, while knowledge of energy requirements, adequate energy composition for snacks, usefulness of labels, understanding the contents of labels, and ease of label use were important factors in the transition from readers to actors. It is suggested from the results that clarification of required dietary habits before learning basic nutritional knowledge and accepting the usefulness and ease of label use are needed before education in label use can be effective.
The effects were investigated of aging and a high-phosphorus (P) diet on bone metabolism in mice. C57BL/6J strain mice, aged 4, 12, 24 and 80 weeks, were randomly divided into two experimental groups (C and HP), each at the same age, one group being fed with a control diet (0.5% P) and the other with a high-P diet (1.0% P) for 28 days. The results with the control diet showed the 80-week-old mice to have a higher serum parathyroid hormone (PTH) concentration than the mice at the other ages. The serum osteocalcin concentration and urinary excretion of the C-terminal telopeptide of type I collagen (CTx) were significantly lower in the 12, 24 and 80-week-old mice than in the 4-week-old mice, the urinary CTx excretion being significantly higher in the 80-week-old mice than in the 24-week-old mice. The breaking force and stiffness of the femur were both significantly higher in the 12, 24 and 80-week-old mice than in the 4-week-old mice, the stiffness of the femur being significantly lower in the 80-week-old mice than in the 24-week-old mice. The high-P diet resulted in a higher serum PTH concentration in the 12, 244 and 80-week-old mice, and a higher serum osteocalcin concentration and urinary CTx excretion in the 4, 12, 24 and 80-week-old mice than in the same-age animals fed on the control diet. The breaking force of the femur was significantly decreased by the high-P diet in the 80-week-old mice, while the stiffness of the femur was significantly decreased by the high-P diet in the 24 and 80-week-old mice. These results suggest that the high-P diet increased the bone turnover at all stages of life. Furthermore, the high-P diet seemed to have a greater effect on bone metabolism in the old mice than in the young and adult mice from the different response in PTH secretion.