Few studies have assessed the association between health literacy (HL) and healthy lifestyle characteristics among Japanese people, and reports on the association between HL and prevalence of metabolic syndrome are also scarce. The present cross-sectional study included 1817 (781 men and 1036 women) Japanese individuals who participated in a medical health checkup at Bange Kosei General Hospital and Takada Kosei Hospital in Fukushima, Japan, from April 2013–2014. Information regarding HL and healthy lifestyle characteristics listed in Breslow’s seven health practices was collected by self-administered questionnaire. In multivariate logistic analysis, higher HL (≥14) was positively associated with healthy lifestyle characteristics [odds ratio (OR) = 2.08, 95 % confidence interval (CI) = 1.33–3.23] and inversely associated with prevalence of metabolic syndrome (OR = 0.67, 95 % CI = 0.48–0.95) among men. Among HL items, the ability to make decisions based on health-related information was significantly associated with healthy lifestyle characteristics (OR = 2.04, 95 % CI = 1.34–3.10 for men, OR = 1.38, 95 % CI = 1.30–1.85 for women) and inversely associated with prevalence of metabolic syndrome (OR = 0.62, 95 % CI = 0.44–0.88 for men, OR = 0.68, 95 % CI = 0.49–0.95 for women) in both sexes. We found positive associations between HL and healthy lifestyle characteristics and an inverse association with prevalence of metabolic syndrome among men. Our findings also suggest that men and women are likely to engage in health-promoting behaviors and make decisions based on health-related information. These findings highlight the importance of comprehensive assessments, including HL, for health promotion in the community.

Objective The aim of this study was to establish a causal relationship between excess body weight and the onset of diabetes in a retrospective cohort study. Methods This 10-year observational cohort study investigated 969 men and 585 women (23 to 80 years of age), who underwent voluntary complete medical check-ups and an annual 75-g oral glucose tolerance test (75 g-OGTT). Participants with fasting plasma glucose ≥126 mg/dL, 2-h glucose level in a 75 g-OGTT ≥200 mg/dL and/or received medical treatment for type 2 diabetes during the previous year were considered as new-onset diabetics. We assessed the independent contribution of increased BMI to the risk of developing type 2 diabetes with Cox proportional hazard model. Result During the follow-up period, we diagnosed 86 men and 49 women with new-onset type 2 diabetes. In the Cox proportional hazards model, the risk of diabetes mellitus increased with increasing BMI, even after adjusting for age, sex, blood pressure, metabolic profiles, and insulin resistance. In the final model, setting BMI less than 25 as a reference group, the Hazard ratios for diabetes mellitus was 3.12 for those with a BMI of 25-27.4 and it was increased to 3.80 for participants with a BMI of 27.5 or higher. Conclusion Overweight/obesity (high BMI) is an independent and dose-dependent risk factor for type 2 diabetes in overweight Japanese patients. Our results confirmed the usefulness of BMI as a classic parameter, and the importance of lifestyle modification and better management among people with overweight/obesity for prevention of type 2 diabetes mellitus.

Background: Mobile health (mHealth) apps are considered to be potentially powerful tools for improving lifestyles and preventing cardiovascular disease (CVD), although only few have undergone large, well-designed epidemiological research. “kencom” is a novel mHealth app with integrated functions for healthy lifestyles such as monitoring daily health/step data, providing tailored health information, or facilitating physical activity through group-based game events. The app is linked to large-scale Japanese insurance claims databases and annual health check-up databases, thus comprising a large longitudinal cohort. Objective: We aimed to assess the effects of kencom on physical activity levels and CVD risk factors such as obesity, hypertension, dyslipidemia, and diabetes mellitus in a large population in Japan. Methods: Daily step count, annual health check-up data, and insurance claim data of the kencom users were integrated within the kencom system. Step analysis was conducted by comparing the 1-year average daily step count before and after kencom registration. In the CVD risk analysis, changes in CVD biomarkers following kencom registration were evaluated among the users grouped into the quintile according to their change in step count. Results: A total of 12,602 kencom users were included for the step analysis and 5473 for the CVD risk analysis. The participants were generally healthy and their mean age was 44.1 (SD 10.2) years. The daily step count significantly increased following kencom registration by a mean of 510 steps/day (P<.001). In particular, participation in “Arukatsu” events held twice a year within the app was associated with a remarkable increase in step counts. In the CVD risk analysis, the users of the highest quintile in daily step change had, compared with those of the lowest quartile, a significant reduction in weight (–0.92 kg, P<.001), low-density lipoprotein cholesterol (–2.78 mg/dL, P=.004), hemoglobin A1c (HbA1c; –0.04%, P=.004), and increase in high-density lipoprotein cholesterol (+1.91 mg/dL, P<.001) after adjustment of confounders. Conclusions: The framework of kencom successfully integrated the Japanese health data from multiple data sources to generate a large, longitudinal data set. The use of the kencom app was significantly associated with enhanced physical activity, which might lead to weight loss and improvement in lipid profile.

Objectives This study aimed to investigate changes in levels of biomarkers associated with adipocyte function and insulin and glucagon kinetics after a meal tolerance test (MTT) during treatment with dapagliflozin among obese type 2 diabetes mellitus (T2DM) patients. Methods T2DM patients with hemoglobin A1c (HbA1c) levels >6.5 % and body mass index (BMI) >25 kg/m² were treated with dapagliflozin 5 mg/day for at least 12 weeks. HbA1c, body weight, ketone bodies, adiponectin, plasminogen activator inhibitor-1 (PAI-1), and C-reactive protein (CRP) were measured before and after treatment with dapagliflozin. A subset of patients underwent an MTT. Results Of 27 participating patients (mean age 47.9 years; 17 males), five were drug-naive and 22 were treated with other antidiabetic agents, including insulin and glucagon-like peptide-1 (GLP-1) receptor agonists. Following treatment with dapagliflozin, HbA1c levels significantly improved (7.44 ± 0.56 to 6.70 ± 0.0.57 %; p < 0.01), body weight significantly decreased (90.9 ± 16.5 to 87.1 ± 15.9 kg; p < 0.01), ketone bodies increased, adiponectin significantly increased, and high-sensitivity CRP tended to decrease. During the MTT, blood glucose ΔAUC₂ significantly decreased, glucagon ΔAUC₂ increased, and immunoreactive insulin (IRI) did not change in 11 of 27 patients. Conclusion Although ketone bodies increased significantly, adiponectin increased and high-sensivity CRP decreased significantly. These findings suggest that sodium-glucose cotransporter-2 (SGLT2) inhibitors may potentially improve adipocyte function in treating obese T2DM patients.

Background: Studies that have examined serum zinc deficiency/marginal deficiency in developed countries, including Japan, are still limited. The aim of this study was to assess serum zinc concentrations and associated characteristics among Japanese subjects.Methods: This cross‐sectional study, conducted from September 2016 to December 2018, included 2056 eligible subjects who participated in a voluntary health checkup. Serum zinc concentration categories were defined as deficiency (<60 μg/dL), marginal deficiency (≥60 to <80 μg/dL), and normal (≥80 μg/dL). Serum zinc concentrations were compared between the first age category (<40 years) and other age categories with Dunnett's method. Trends in P‐values were estimated using the Jonckheere‐Terpstra test for continuous variables.Results: The proportions of subjects with deficiency and marginal deficiency were 0.4% and 46.0% in men, and 0.6% and 38.4% in women, respectively. The deficiency/marginal deficiency group had significantly lower lipid profiles and nutritional status, and a significantly lower proportion were non–daily drinkers in both genders. Older age was significantly associated with lower serum zinc concentration only in men.Conclusions: Our findings clarified a high proportion of serum zinc deficiency/marginal deficiency, especially in men, and suggest a possible association between serum zinc levels and nutritional status and alcohol consumption. It may be necessary to manage nutritional status, including zinc intake.