Background: Loneliness, a feeling of distress, has aggravated due to the COVID-19 pandemic lockdowns and reduced social interactions. The objective of this study was to explore whether increased loneliness due to the COVID-19 pandemic was associated with various eating and activity behaviours in adolescence, a critical period for the development of lasting lifestyle habits. Methods: In this cross-sectional study, we used self-reported data from 43,588 and 40,521 Canadian adolescents aged 12-19 years (collected between November 2020 and June 2021) for eating habits and the 24-hour movement behaviours, respectively. Binary and multinomial logistic regression were used to predict the odds of various lifestyle behaviours among adolescents with increased loneliness due to the COVID-19 pandemic. Results: We found higher odds of skipping breakfast [boys: OR 1.41 (95% CI: 1.33, 1.50), girls: OR 1.64 (95% CI: 1.56, 1.74)], fast food consumption [1-2 days in the past week: girls - OR: 1.14 (95% CI: 1.08, 1.21); ≥3 days in the past week: boys - 1.12 (95% CI: 1.02, 1.24), girls - OR: 1.42 (95% CI: 1.29, 1.57)], not meeting screen time [boys: OR 1.43 (95% CI: 1.24, 1.66), girls: OR 1.72 (95% CI: 1.54, 1.92)], and sleep duration guidelines [boys: OR 1.38 (95% CI: 1.28, 1.48), girls: OR 1.36 (95% CI: 1.27, 1.45)] among adolescents that reported increased loneliness due to the pandemic (versus those in the decreased/stayed the same loneliness group). Conclusion: Future longitudinal studies in adolescents are needed to confirm the directionality of these associations. It is important to raise awareness of these findings among public health practitioners, policymakers, physicians, schools and parents to promote healthier eating habits and increase adherence to the 24-hour movement behaviours. Recovery efforts post-pandemic are needed to reduce loneliness levels to support adolescent social health and establish healthy behavioural habits across the lifespan.

BACKGROUND: China has seen rapid increase in obesity and hypertension prevalence and fast food consumption over the past decade. We examined status and risk factors for Western- and Chinese fast food consumption and their associations with health outcomes in Chinese children, and examined how maternal factors were associated with child health outcomes. METHODS: Data of 1626 students aged 7-16 (11.6 ± 2.0) years and their parents in four mega-cities across China (Beijing, Shanghai, Nanjing, and Xi'an) were collected in the 2015 baseline survey of the Childhood Obesity Study in China Mega-cities. Weight, height, waist circumference, and blood pressure were measured. Food intake was assessed using questionnaire. Mixed models were used to examine the associations. RESULTS: Among the children, 11.1% were obese, 19.7% were centrally obese, and 9.0% had hypertension. Obesity prevalence was much higher in boys than in girls (15.2% vs. 6.9% and 27.4% vs. 11.7%, respectively, both P < 0.001). About half (51.9% and 43.6%) of children consumed Western and Chinese fast food, respectively, over the past 3 months. Compared to those with college or above maternal education level, those with elementary school or below maternal education level were 49% more likely to consume Western fast food (odds ratio [OR] and 95% confidence interval [CI]: 1.49 [1.10-2.03]). Chinese fast food consumption rate increased by 12% with each year of increase in child's age (OR and 95% CI: 1.12 [1.02-1.23]). No significant associations between fast food consumption and health outcomes were detected. Adjusting for Western fast food consumption, children with lower maternal education were 71% and 43% more likely to have obesity and central obesity (ORs and 95% CIs: 1.71 [1.12-2.61] and 1.43 [1.00-2.03], respectively), and maternal body mass index was positively associated with child obesity, central obesity, and hypertension (ORs and 95% CIs: 1.11 [1.06-1.17], 1.12 [1.07-1.17], and 1.09 [1.03-1.15], respectively). Results were similar when Chinese fast food consumption was adjusted for. CONCLUSIONS: The prevalence of fast food consumption, obesity and hypertension is high among children in major cities in China. Maternal factors affect child outcomes.