Background Myopia is a pervasive global public health concern, particularly among the younger population. However, the escalating prevalence of myopia remains uncertain. Hence, our research aims to ascertain the global and regional prevalence of myopia, along with its occurrence within specific demographic groups. Methods An exhaustive literature search was performed on several databases covering the period from their inception to 27 June 2023. The global prevalence of myopia was determined by employing pooled estimates with a 95% CI, and further analysis was conducted to assess variations in prevalence estimates across different subgroups. Additionally, a time series model was utilised to forecast and fit accurately the future prevalence of myopia for the next three decades. Results This study encompasses a comprehensive analysis of 276 studies, involving a total of 5 410 945 participants from 50 countries across all six continents. The findings revealed a gradual increase in pooled prevalence of myopia, ranging from 24.32% (95% CI 15.23% to 33.40%) to 35.81% (95% CI 31.70% to 39.91%), observed from 1990 to 2023, and projections indicate that this prevalence is expected to reach 36.59% in 2040 and 39.80% in 2050. Notably, individuals residing in East Asia (35.22%) or in urban areas (28.55%), female gender (33.57%), adolescents (47.00%), and high school students (45.71%) exhibit a higher proportion of myopia prevalence. Conclusion The global prevalence of childhood myopia is substantial, affecting approximately one-third of children and adolescents, with notable variations in prevalence across different demographic groups. It is anticipated that the global incidence of myopia will exceed 740 million cases by 2050.

Background: Depression escalating public health concern and the modest efficacy of currently available treatments have prompted efforts to identify modifiable risk factors associated with depression symptoms. Physical inactivity, poor nutrition, or other lifestyle behaviors are among the potentially modifiable risk factors most consistently linked with depression. Past evidence regarding the single effect of physical activity (PA) or dietary quality (DQ) on reducing the risk of depression symptoms has been well-documented. However, the association of the joint effect of PA and DQ on depression symptoms has never been investigated in a representative sample of adults. Objective: This study investigates the association between PA and depression symptoms and between DQ and depression symptoms, and their combined effects on US adults. Methods: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2007 to 2018 cycles. The primary exposures were DQ and PA, measured using the Healthy Eating Index (HEI)-2015 and the metabolic equivalent (MET) minutes per week reported in questionnaires, respectively. Depression symptoms were defined as a 9-item Patient Health Questionnaire (PHQ-9) score of ≥10. We created 4 lifestyle categories: healthy diet and active individuals, unhealthy diet but active individuals, healthy diet but inactive individuals, and unhealthy diet and inactive individuals. Participants were considered to have a healthy diet if they fell within the 60th percentile of the HEI-2015 or to be active if they met the current guidelines for PA. A survey-multivariable logistic regression approach was used to model adjust the variables relevant to the associations, and an age-adjusted prevalence for depression symptoms was calculated following the NHANES guidelines. Results: In total, 19,295 participants represented a weighted number of 932.5 million adults aged 20 to 80 years in the noninstitutionalized US population. The total age-adjusted prevalence of depression symptoms among all respondents was 7.08% (1507/19,295). Of the respondents, 81.97% (15,816/19,295) met the PA recommendation and 26.79% (5170/19,295) scored at or above the 60th percentile on the HEI-2015. Depression symptoms were inversely associated with a higher level of PA (adjusted odds ratio [AOR] 0.819, 95% CI 0.716-0.938) and healthy DQ (AOR 0.809, 95% CI 0.701-0.931), respectively. A healthy diet combined with recommended PA was associated with a significantly lower risk of depression symptoms (AOR 0.658, 95% CI 0.538-0.803) than those who consumed an unhealthy diet but were physically active (AOR 0.890, 95% CI 0.765-1.038) or consumed a healthy diet but were physically inactive (AOR 1.077, 95% CI 0.817-1.406). Conclusions: Our findings indicate that people with a healthy diet and recommended PA have a lower risk of depression symptoms than those with an unhealthy diet and a low level of PA. A healthy dietary habit and regular PA are potential precautions against depression.

We investigated the consumption of sugar-sweetened beverage (SSB) and its association with obesity and hypertension in a national sample of children and adolescents in China, where many low- and middle-income families live. Data were obtained from a 2014 national intervention program against obesity in Chinese children and adolescents aged 6–17 years. Height, weight, waist circumference, and blood pressure were measured. Information of SSB consumption, socioeconomic status, dietary intake, screen time, and physical activity were self-reported. Multivariate logistic regression was used to assess the association of SSB consumption with obesity and hypertension. A total of 66.6% of the 53,151 participants reported consuming SSB. The per capita and per consumer SSB intake were 2.84 ± 5.26 servings/week and 4.26 ± 5.96 servings/week, respectively. Boys, older children, and adolescents, and individuals with long screen time or high physical activity or low parental education level were more likely to consume SSB. Participants who were high SSB consumers had a higher odds ratio (1.133, 95% CI: 1.054–1.217) than non-consumers for having abdominal obesity after adjustment for age, sex, residence, socioeconomic status, diet, screen time, and physical activity. However, SSB consumption was not associated with general obesity or hypertension in children and adolescents. In conclusion, more than half of the children and adolescents in China consumed SSB, which was independently related to a high risk of abdominal obesity. The results of this study indicated that SSB reduction strategies and policies may be useful in preventing obesity among Chinese children and adolescents.

The prevalence of obesity among children and adolescents has been rapidly rising in Mainland China in recent decades, both in urban and rural areas. There is an urgent need to develop effective interventions to prevent childhood obesity. Limited rigid data regarding children and adolescent overweight prevention in China are available. A national random controlled school-based obesity intervention program was developed in the mainland of China. The study was designed as a national multi-centered cluster randomized controlled trial involving more than 70,000 children and adolescents aged 7–18 years from 7 provinces in China. In each center, about 12–16 primary and secondary schools, with totally at least 10000 participants were randomly selected (Primary: Secondary = 1:1). All of the selected schools were randomly allocated to either intervention or control group (Intervention: Control = 1:1).The multi-components school-based and family-involved scheme was conducted within the intervention group for 9 month, while students in the control group followed their usual health practice. The intervention consisted of four components: a) Create supportive school and family environment, b) Health lifestyles education and related compulsory physical activities, c) Instruct and promote school physical education, d) Self-monitor obesity related behaviors. Four types of outcomes including anthropometric, behavioral, blood chemical and physical fitness were measured to assess the effectiveness of the intervention program. This is the first and largest multi-centered school-based obesity intervention program with the consideration of geographical and social-demographic characteristics of the rapidly increased obesity prevalence of Chinese children and adolescent. The intervention is based on Social Cognitive Theory and Social-Ecological Model of Health, and follows a stepwise approach guided by PRECEDE-PROCEED (P-P) Model and Intervention Map. The results of and lesson learned from this study will help guide future school-based national childhood obesity prevention programs in Mainland China. January 22, 2015; Registration number: NCT02343588

The prevalence of metabolic syndrome (MetS) rapidly increased over the past decades. However, little evidence exists about the effects of long-term exposure to ambient air pollution on MetS in children and adolescents. This study aims to assess the association between long-term ambient air pollution and the prevalence of MetS in a large population of Chinese children and adolescents. In 2013, a total of 9,897 children and adolescents aged 10 to 18 years were recruited from seven provinces/municipalities in China. MetS was defined based on the recommendation by the International Diabetes Federation (IDF). Satellite based spatio-temporal models were used to estimate exposure to ambient air pollution (including particles with diameters ≤1.0 µm (PM1), ≤2.5 µm (PM2.5), and ≤10 µm (PM10), and nitrogen dioxide (NO2)). Individual exposure was calculated according to 94 schools addresses. After adjustment for a range of covariates, generalized linear mixed-effects models were utilized to evaluate the associations between air pollutants and the prevalence of MetS and its components. In addition, several stratified analyses were examined according to sex, weight status, outdoor physical activity time, and sugar-sweetened beverages (SSBs) intake. The prevalence of MetS was 2.8%. The odds ratio of MetS associated with a 10 μg/m3 increase in PM1, PM2.5, PM10 and NO2 was 1.20 (95%CI: 0.99, 1.46), 1.31 (95%CI: 1.05, 1.64), 1.32 (95%CI: 1.08, 1.62), and 1.33 (95%CI: 1.03, 1.72), respectively. Regarding the MetS components, we observed associations between all pollutants and abdominal obesity. In addition, long-term PM1 and NO2 exposures were associated with the prevalence of elevated fasting blood glucose. Stratified analyses detected that the associations between air pollutants and the prevalence of MetS were stronger in boys (Pinteraction < 0.05). We found that long-term exposure to PM2.5, PM10, and NO2 were positively associated with the prevalence of MetS in children and adolescents. Our findings may have certain public health implications for some comprehensive strategy of environment improvement and lifestyles changes in order to reduce the burden of non-communicable disease.