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The objectives of this thesis were to: (1) examine the sex/gender-specific impacts that employment status change (employment transitions, ETs) have on body weight and waist circumference (WC) changes in middle- and older-age adults and (2) assess the contribution of changes in health behaviours (HBs: sleep duration and quality, smoking status, alcohol consumption, and physical activity) in the association between ETs and anthropometric changes.Chapter 1: Eight bibliometric databases were systematically searched, with citations followed up. Twelve studies were included. All studies examined retirement but reported mixed results. Retirement either led to weight gain or did not alter weight compared to non-retirement. Occupation type modified the association: weight gain was more commonly reported among retirees from physically demanding occupations. Two included studies also examined job-loss and results were also mixed. Key confounders and commonly studied HBs were identified.Chapter 2 & 3: Two waves of data from the Canadian Longitudinal Study on Aging were used to classify 10,117 working women and men into three ET groups: stayed working, entered retirement, and stopped working. The outcomes were change in weight and WC on continuous scales, and change as categories (≥5% gain, ≥5% loss, no change). Multivariable linear and multinomial logistic regressions were adjusted for confounders and HBs.Multivariable linear regression models showed that weight changes did not differ across ETs in women, although changes in WC showed different directions across ET. By contrast, men who entered retirement lost more weight and had greater reductions in WC relative to men who stayed working (-0.59 kg, [95% CI: -1.11, -0.08] and -0.83 cm, [95% CI: -1.46, -0.20]). Final multinomial logistic regression models did not show significant associations; however, the direction of the effects remained. In models that included HB change variables, estimates were not attenuated. Retirement may result in small amounts of weight loss in middle-aged and older Canadian men. Work stoppage appears to lead to more WC increases in women, but the evidence is uncertain. Contrary to hypotheses that place HBs along the pathway between ETs and anthropometric change, the findings from the empirical study suggest that they are independent risk factors instead.

Food insecurity, diet-related chronic illnesses, and climate change have become more prominent in public health and education policy, leading to the identification of many policy and program gaps in our food and education systems. Research shows young adults finishing secondary school without consistent food education lack knowledge of basic nutrition, food skills, food systems, everyday food practices, and food production. School farms as food literacy interventions can positively impact food literacy and food security. Links have been established between food literacy and food system knowledge and healthier food practices to decrease diet-related diseases like obesity and diabetes amongst individuals and improve overall community health and well-being. However, little research exists on self-identifying school farms as unique and specific programs or their connection to food literacy in secondary schools. This community-based research study aimed to develop a working definition of ‘school farm’ and understand school farms’ capacity to build adolescent food literacy. I used semi-structured interviews with multiple stakeholders (n=18) across 6 school farms in British Columbia, Canada, and applied Framework Analysis using food literacy and community-determined frameworks as well as inductive coding to analyse qualitative data. My analysis showed that school farms are defined by 1) food production capacity and scale; 2) community integration, and 3) experiential educational opportunities to teach food systems and core curricula. School farms offer comprehensive food literacy education, including individual and collective food system skills, behaviours, and knowledges, to improve personal, community, and environmental health. My data also revealed school farms’ positive impacts on students’ mental health and well-being, and the academic success of neurodivergent and culturally diverse students who often struggle in traditional formal education settings. Additionally, the data indicated school farms face major barriers like funding, sustainability, and management obstacles. This study helps to clarify the concept of school farms and explain how they contribute to student food literacy, especially within the context of British Columbia.

Background: Sleep deficits, which include social jetlag, poor sleep quality, and short sleep duration, have been commonly observed in adolescents due to development-specific late chronotype, early school start time, and other physiological and environmental factors. Recent findings indicate that sleep is potentially associated with unhealthy eating habits, such as frequent consumption of sugar-sweetened beverages (SSB). The associations may also differ by gender. This thesis examined the gender-specific associations between three different types of sleep deficits and SSB consumption among adolescents. Methods: This thesis used a cross-sectional study design and included 1031 adolescents from Wave 6 (Spring 2012) of the British Columbia Adolescent Substance Use Survey (BASUS) (mean age: 15±0.7 years). Descriptive statistics analyzed the prevalences of self-reported sleep deficits and SSB consumption by gender. Multivariable logistic regression models using interaction terms examined the associations between each sleep deficit variable and three measures of SSB consumption, by gender. Additional confounders were included in the sensitivity analyses to test the robustness of results. Results: Compared to no social jetlag (≤ 1h), consistent positive associations of higher social jetlag levels were observed with above-median (OR 1.63 (95% CI: 1.01, 2.65)) and any weekly SSB intake (1.97 (1.06, 3.66)) in girls; boys showed a similar positive but non- statistically significant OR trend with any SSB intake. Non-significant positive associations were seen between more frequent restless sleep and daily SSB intake in girls, but only boys with occasional restless sleep (1-2 days/week) had significantly higher odds of any SSB intake (3.21 (1.31, 7.88)), compared to no restless sleep (