The influence of lifestyle on the incidence of dental caries among 3-year-old Japanese children.

The present cohort study examined how lifestyle, household environment, and caries activity test score of Japanese children at age 1.5 years affected their dental caries incidence at age 3. Inclusion criteria were 1.5-year-old children with no dental caries. Dental examinations were performed for 33,655 children who participated in routine dental examinations at 1.5 years of age, and the exam was repeated approximately 21 months later (at age 3) at the Kobe City Public Health Center in Japan. After excluding 622 children who had caries at age 1.5 and 1831 children with missing lifestyle and household environment data in the questionnaires, the final data analysis was performed on a total of 31,202 children (16,052 boys, 15,150 girls).The multivariate logistic regression analysis indicated a strong association of the consumption of sugar-sweetened beverages/snacks, less frequent tooth brushing by the parents, lack of fluoride varnish, family history of smoking, with the risk of developing dental caries. A child's late bedtime is also one of the major risk factors for dental caries development. Further investigation is needed to examine whether the short duration or the irregularity of the sleep-wake cycle would affect early childhood oral health and whether there is a relationship between late bedtime and late night snack intake.

Association of dietary fat and carbohydrate consumption and predicted ten-year risk for developing coronary heart disease in a general Japanese population.

We examined the relationships between dietary carbohydrate, protein, fat, and the ratio of n6/n3 fatty acid intakes with the predicted 10-year coronary heart disease (CHD) risk in a general Japanese population. We used the Framingham risk score to determine the 10-year CHD risk of the subjects, who were employees of 6 companies in a single prefecture in Japan. After excluding the subjects who reported any history of angina pectoris, myocardial infarction, diabetes, or cancer, and those with missing data resulting in the inability of estimation of 10-year CHD risk and food intakes, the final data analysis was carried out for 809 subjects. The logistic regression models revealed a significantly increased odds ratio of 10-year CHD risk in the subjects with the highest tertile of carbohydrate intake (% energy) (odds ratio 3.64, 95% CI, 2.07-6.40); after adjustment for other variables, the odds ratio for the 10-year CHD risk was also higher in the subjects with the highest tertile of carbohydrate intake (odds ratio 1.72, 95% CI, 0.70-4.25). We also found that fat intake and the ratio of n6/n3 fatty acids were inversely associated with the predicted 10-year CHD risk (p for trend<0.01). The present findings added evidence of a positive association of dietary carbohydrate and inverse associations of total fat and n6/n3 fatty acid ratio with the predicted 10-year CHD risk in a general Japanese population.

Associations of serum retinol, α-tocopherol, and γ-tocopherol with biomarkers among healthy Japanese men.

Retinol, α-tocopherol, and γ-tocopherol are fat-soluble vitamins acting as antioxidants via the prevention of lipid oxidation. Little is known about circulatory levels in healthy individuals. The present cross-sectional study aimed at elucidating the relationship between these antioxidants and clinical biomarkers in 206 male (median age 41 years, range 23-67) employees from companies located in the Okayama Prefecture, Japan. Subjects younger than 40 years (n = 94) showed a positive association of the frequency of alcohol consumption with the circulating retinol (ß = 0.344, p = 0.001) and γ-tocopherol levels (ß = 0.219, p = 0.041), and an inverse association of fast insulin with serum retinol (ß = -0.301, p = 0.009). In participants older than 40 years (n = 112) we found that an inverse association of HOMA-R with serum retinol (ß = -0.262, p = 0.021), α-tocopherol (ß = -0.236, p = 0.035), and γ-tocopherol levels (ß = -0.224, p = 0.052); and cigarette smoking was inversely associated with the levels of serum α-tocopherol (ß = -0.286, p = 0.008) and γ-tocopherol (ß = -0.229, p = 0.040). We further found negative relationships between serum ferritin and the retinol (ß = -0.211, p = 0.032) and α-tocopherol levels (ß = -0.223, p = 0.022) in men over 40 years of age. The present study suggests that the circulatory levels of antioxidant vitamins may modulate the action of insulin and that higher levels of iron might decrease the levels of antioxidant vitamins in the blood.