Lifestyle-related diseases including hypertension, diabetes, obesity and hypercholesterolemia are the results of both genetic and environmental factors. The genetic factor is mainly composed of single nucleotide polymorphism (SNP) and environmental factors include diet, exercise, drinking and smoking. The ethnic difference in the frequency of SNP may be caused by natural selection depending on the types of agricultures in human history. The resistance against starvation among Japanese is caused by many SNPs including those in beta-adrenergic receptor, uncoupling proteins, calpain 10, PPAR-gamma, leptin receptor. Hypertension of Japanese is also caused by SNP for factors retaining salt, such as angiotensinogen, aldosterone synthase and angiotensin converting enzyme. T-type SNP of angiotensinogen was needed for apes living in the tropical forest, but is predisposing hypertension in the modern society. The ethnic differences in digestion of lactase may be the result of Rabi agriculture, those in aldehyde dehydrogenase and gulonolactone dehydrogenase are caused by the tropical foods. Japanese diet is based on the Ubi agriculture of Jomon era since 10, 000 years before present (YBP), and rice growing of Yayoi era since 3, 000 YBP. However, there are strong impacts of westernization including that of Rabi agriculture after 1945. We have studied SNPs in Palau as a model of Mongoloids because of their rapid increase in diabetes by westernization. SNPs saving energy were found in PPAR-gamma, UCP3 promotor, leptin receptor etc.(Biochem. Biophys. Res. Commun., 281, 772, 2001). We also analyzed SNPs of the patients who were educated 25-31 years ago. Despite differeces in SNPs (betaadrenergic receptor, apoE and mtDNA), the special dietary habits (four-group point method) prevented most of the lifestyle-related diseases. Finally, total analysis of mtDNA from patients of encephalomyopathy detected three new mutation points. In conclusion, the merit of traditional Japanese diet will prevent Japanese from obesity and diabetes mellitus, because of their special SNPs regulating metabolism.
A food frequency questionnaire (FFQg) was developed, based on 29 food groups and 10 kinds of cookery, for estimating the energy and nutrient intakes of an individual subject during the previous one to two months. This questionnaire was evaluated by a comparison with weighed dietary records for 7 continuous days (7d records) of 66 subjects aged 19-60 years. The correlation coefficients between the FFQg and 7d records for energy, protein, fat, carbohydrate and calcium intakes were 0.47, 0.42, 0.39, 0.49 and 0.41, respectively. The intakes of 26 of the 31 nutrients were not significantly different by paired t-tests between the two methods (p≥0.05). The ratio of the value obtained by the FFQgmethod against that by the 7d records method ranged from 72%(vitamin B12) to 121%(vitamin C). The average value of this ratio was 104%. The correlation coefficients for the intakes of rice, bread, meat, fish, milk, dairy products, green-yellow vegetables, other vegetables, and fruits were 0.66, 0.76, 0.27, 0.27, 0.72, 0.58, 0.46, 0.53, and 0.64, respectively, between the FFQg and 7d records, and there was significant correlation between the two methods at the p<0.05 level for 22 of the 29 food groups. Apart from those food groups for which “Less than once a month or never” was selected by 50% or more of the respondents, 34% of respondents could estimate portion sizes in the FFQg with an error of less than 25%. The results show that the FFQg record is a useful instrument for estimating individual energy and nutrient intakes.
Effects of 8-weeks low-intensity aerobic training on the body composition and basal metaboli sm were evaluated in untrained young females. Twelve subjects randomly divided into two groups. One group was sedentary control. The other half exercised at an intensity of 50% of the maximal aerobic capacity for 30 minutes per day, 4days a week for 8 weeks. Altough maximal aerobic capacity was improved by training the body weight, percent of fat, and lean body mass were not different between before and after training. The basal metabolic rates (BMR), expressed by per day, per body weight, and per lean body mass, decreased significantly (p<0.05) after training, -9%, -8%, -8%, respectively. The blood thyroid hormone, T3, concentration was significantly reduced after training (p<0.001), and T4 and free T4 concentrations also decreased significantly (p<0.05). However, no significant correlation was observed between the decrease of the thyroid hormone level and that of BMR. There were no differense in the daily energy intake of the subjects between before and after training. Interestingly, the estimated daily energy expenditure was reduced after training. This might be related to an increase of sleep-time, and decrease of daily activity level. These results suggest that 8-weeks low-intensity aerobic training did not change body composition in untrained young females, because training resulted reducing the daily activity level, and consequently decreased of BMR and blood thyroid hormone concentrations.
This study examines the influential factors that form the ideal dietary attitude of an undergraduat e majoring in nutrition. The participants were 156 female college students (78 first-year students and 78 third-year students) studying to be dietitians. We first asked them 85 questions about their views on ideal diet ary habits and attitudes. Four factors based on 24 questions clearly emerged from a factor analysis of this questi onnaire; they were “eating satisfaction”, “food culture”, “nutrition” and “cooking”. We confirmed the reliability issues by Cronbach's alpha and test-retest. We also surveyed the same students by using the KC-Food Choice Questio nnaire. Several correlations were found in both questionnaires:“eating satisfaction” was correlated with“mood” and “sensory appeal”;“nutrition” was linked to “health” and “weight control”;“food culture” was correlat ed with “natural content”; and “cooking” was related to both “mood” and “convenience”. By comparing the score for the four factors between the first-year and third-year students, the “nutrition” score was found to be higher among the first-year students, whereas the “food culture” score was higher among the thi rd-year students. In addition, the students who had the strongest desire to become dietitians had a high score for “nutrition”. We suggest that understanding eating behavior such as the factors that form ideal dietary attitudes among students majoring in nutrition is important for their education.