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Excess body weight in women of child-bearing age can have severe consequences for maternal and child health, including reduced fertility, pregnancy complications, an increased risk of child obesity and increased susceptibility to non-communicable diseases. Black women and children in high-income countries (HICs) have a disproportionately higher prevalence of overweight and obesity compared to other ethnic groups. However, there is a lack of evidence on the weight status of African migrant women and children living in HICs, and on these women's weight perceptions and perceived risks of overweight and obesity. In the first phase of this thesis, I used systematic review, meta-analysis and framework synthesis methods to explore the weight status of African migrant women and children living in HICs, and the dietary and physical activity (PA) behaviours of African migrant women. Metaanalyses results showed that African migrant women had higher body mass index (BMI) (weighted mean difference (WMD)=1.95 Kg/m2, 95%CI 1.16-2.75) and higher odds of overweight (OR=2.45, 95%CI 1.65-3.63), obesity (OR=2.09, 95%CI 1.41-3.12) and combined overweight/obesity (OR=2.09, 95%CI 1.41-3.12) compared to non-African women from HICs. Children of African migrant women also had higher mean birthweights (WMD=48.71g, 95%CI 4.19g-93.24g), higher odds of overweight (OR=1.50, 95%CI 1.00- 2.24), obesity (OR=2.28, 95%CI 1.37-3.78), combined overweight/obesity (OR=2.08, 95%CI 1.40-3.11) and macrosomia (OR=1.83, 95%CI 1.77-1.89), and lower odds of low birthweight (OR=1.06, 95%CI 0.56-2.02) compared to children of non-African women. Risks of overweight and obesity were higher for women and children from North Africa, while data were lacking for sub-Saharan Africa. African migrant women had bicultural dietary patterns, inadequate intakes of iron, folate, and calcium, excessive sodium intakes, and reduced PA levels. There were data gaps on potential confounders that may influence maternal and child weight status, associations between maternal characteristics and child weight outcomes, and weight-related behaviours of pregnant African migrant women. In the second phase, I explored the weight perceptions of African migrant women living in the UK, their perceived risks of overweight and obesity to themselves and their children, and the sociocultural and migration-related influences of these. Interviews conducted with 23 African migrant women from Nigeria, Ghana and Cameroon were analysed through thematic analysis. Key themes identified were: 'we are not at risk', 'bigger is better', acculturation, 'a child cannot be too fat' and infant feeding as a balancing act. The women's perceptions were influenced by their understandings and lay interpretations of body weight terms, which differed from mainstream knowledge. Perceived risk factors for obesity included: diet, genetics, childbearing and living the 'easy life' in the UK. PA was mostly interpreted as sport or exercise and was not an intrinsic part of their culture. Post-migration changes in weight perceptions included increased knowledge of healthy weight-related behaviours, awareness of unhealthy cultural practices and preference for smaller body sizes (for themselves but not their children). Pregnancy was associated with heightened weight-awareness, while preconception weight was believed to have no influence on women's health or pregnancy. Midwives and relatives were useful information sources for pregnancy weight, and challenges with weight management in pregnancy included families encouraging weight gain; food cravings; unhealthy food in the UK and unfamiliar dietary advice from midwives. Women tended to disregard weight-related advice from health care providers, while valuing advice from friends and family. This thesis identifies African migrant women and children as high-risk groups for overweight and obesity, and highlights the role of migration and socio-cultural influences on their weight status, behaviours and perceptions. There is a need for culturally-tailored interventions to support weight management in this population, especially taking into account their multicultural identities. Further research and interventions addressing the risk factors and areas of need identified could help prevent further increases in obesity, and contribute towards narrowing the inequality gaps in health outcomes among migrant populations in HICs.

Studies investigating atherothrombotic risk in women with polycystic ovary syndrome (PCOS), in particular platelet function and carotid intima-media wall thickness (cIMT), have been confounded by not adequately accounting for obesity. Liraglutide is a glucagon like peptide-1 (GLP-1) analogue that causes weight loss and may have favourable effects on atherothrombotic risk and liver fibrosis in preclinical and animal studies. The aims of this study was to investigate whether atherothrombotic risk was increased in obese women with PCOS independently of obesity; whether GLP-1 receptor (GLP-1R) is expressed in human platelets; and whether 6 months treatment with liraglutide would improve weight and markers of atherothrombosis and liver fibrosis in obese young women with PCOS and/or normal controls. Our results suggest that PCOS, independent of obesity, is associated with increased levels of insulin resistance, inflammation, oxidative stress, non-alcoholic fatty liver disease (NAFLD) and the liver fibrosis marker PIIINP. However, PCOS was not independently associated with increased atherothrombotic risk markers including cIMT, platelet function, clot function/lysis, and endothelial function. Treatment for 6 months with liraglutide, 1.8mg daily, resulted in 3 – 4% weight loss in obese women with PCOS and controls. This was associated with a significant reduction in insulin resistance, oxidative stress, and several markers of atherothrombosis including inflammation, serum biochemical markers of endothelial function and clot lysis. Although basal platelet activation was reduced in the control group only and the liver fibrosis marker PIIINP was only reduced in the PCOS group, between groups comparisons were not significant. No change was observed in cIMT. In addition, we demonstrated for the first time that platelets express the GLP-1R. Liraglutide inhibited collagen- and thrombin-induced aggregation in isolated platelets and the effects were at least partly mediated by the GLP-1R, although an additional GLP-1R independent pathway is also likely. In conclusion, cardiovascular risk in young obese women with PCOS can either be attributed to obesity or is not yet apparent at this early stage of the condition. Our data support the use of liraglutide as a weight loss medication in simple obesity and suggest a potential beneficial effect on atherothrombotic risk and markers of liver fibrosis at 6 months of treatment. GLP-1R is a novel receptor in platelets and its function and clinical effect are worth further evaluation.

Background: Pregnancy is a trigger point for the development of obesity with maternal obesity being associated with significant adverse effects in the mother and child. Nigeria is experiencing a double burden of under- and over-nutrition with rising levels of obesity particularly in women. However, there is scarcity of data on maternal obesity in Nigeria and other African countries. Aims and Objectives: This thesis aimed at identifying crucial components of potential interventions for maternal obesity in Nigeria. The objectives were to assess the prevalence, effects and distribution of maternal obesity; assess the knowledge, attitude and practice (KAP) of pregnant women and maternal healthcare providers and identify existing interventions for maternal obesity in Nigeria. Methodology: A systematic review and meta-analysis was initially conducted. Following this, a quantitative questionnaire survey of the KAP of pregnant women and a qualitative interview study of the KAP of Health Care Workers (HCW) were conducted in seven secondary and tertiary hospitals across Nigeria. Quantitative data was analysed with SPSS statistical software, while thematic analysis was conducted for qualitative data. Results: Twenty-nine studies included in the systematic review showed significant prevalence, socio-demographic associations, and adverse effects of maternal obesity on labour, maternal, and child outcomes in Africa. The questionnaire survey of 435 mothers revealed a maternal obesity prevalence of 17.9% among mothers who registered for antenatal care in the first trimester. Mothers had insufficient knowledge of the causes, complications, and safe ways to manage maternal obesity. However, majority felt that excess gestational weight gain be avoided and some practiced weight management during pregnancy. For the qualitative study, four main themes were identified: 'Concerns about obesity in pregnancy', 'Barriers to care for obese pregnant women', 'Practice of care for obese pregnant women', and 'Improving care for obese pregnant women'. Conclusions: Culturally adaptable/sensitive interventions should be developed for the management of obese pregnant women in Africa. Education and training of mothers and health care workers, and provision of guidelines are some of the components of potential interventions in Nigeria.

Conditional cash transfer schemes (CCTS) are increasingly popular interventions aiming to improve the welfare of the worst off: Families receive regular cash as long as they comply with behavioral conditions concerning uptake of preventive healthcare and schooling. Literature Review, however, finds that associated health impacts are often small or inconsistent and are occasionally adverse. The aim of this thesis is to advance understanding of the impact of CCTS on health and on health equity. It does this by examining the effect of Familias, the Colombian scheme, on outcomes little discussed in the literature, namely rates of obesity in women and in children (an unintended outcome), and women’s healthcare knowledge. It sets findings within a conceptual framework that sees health as being co-produced between individuals and society. Co-production requires investment in individuals’ human capital, material resources and creation of fairer socioeconomic environments, somewhat resembling the underpinning philosophy and structure of CCTS. Multiple regression on a range of individual, household and community level covariates using an intention-to-treat protocol on prospectively collected data with matched controls finds that Familias is associated with increased odds of obesity in women (O.R.=1.41, 95% C.I. 1.09, 1.82; p=0.01) and odds of overweight or obesity in girls aged 2-7 at baseline (O.R.=2.13, 95% C.I. 1.23, 3.69; p<0.01). Furthermore, Familias fails to improve healthcare knowledge, a marker of human capital, in women despite being a core objective of the programme (logit coefficient= -0.20, 95% C.I. -0.41, 0.01; p=0.06). Given these negative findings, a number of policy recommendations are made emphasising the importance of social determinants of health: balancing imposition of behavioural requirements with the realisation of rights to high-quality public services, considering the potential for universalising aspects of the schemes and exploring a greater role for the health sector in CCTS design, operation and evaluation.

Background: While taste is a main driver of food choice, food reward is more than just the sensation of taste and interacts with the homeostatic system (e.g. hunger) to create pleasure (liking) and motivation (wanting) for food. Food reward is a driver of food intake and therefore commonly thought to be related to obesity. However, liking/wanting have never been targeted to improve weight management strategies. Objectives: This thesis aims to explore the role of food reward during 1) weight management, 2) weight loss (WL) and no-contact follow-up, and 3) its association with appetite control and obesity in women. Methods: Food reward and appetite-related variables (e.g. body composition, energy intake, eating behaviour traits) were investigated during a controlled-feeding WL, 1-year follow-up and a cross-sectional analysis between women with or without overweight/obesity. Liking and implicit wanting were assessed with the Leeds Food Preference Questionnaire. Results: Contrary to expectations, a systematic review showed that liking and wanting decreased after different weight management interventions. The diet intervention added that liking decreased for all food categories independently from diet modality or improvement in appetite control. After 1-year of no-contact, weight was regained, appetite control weakened and liking returned to baseline levels. Lastly, women with overweight/obesity did not have higher wanting for high-fat sweet but lower wanting for low-fat sweet food compared to women within the normal range of BMI. Importantly, wanting for low-fat food was associated with improved appetite control and less fat mass while it was the contrary for high-fat food. Conclusions: The role of food reward in weight management distinguishes between liking and wanting and high-fat vs low-fat, as its components dissociated during WL and had opposite impact on appetite control. Food reward does not differ greatly between women with or without overweight/obesity and other appetite-related factors are needed to understand obesity status.

High body-mass-index (BMI), hyperglycaemia, and hypercholesterolemia are the leading risk factors for mortality and morbidity worldwide. As obesity has become an epidemic in all age groups globally, more and more women enter pregnancy with obesity. Pregnant women with high BMI often present with excessive gestational weight gain, hyperglycaemia, and dyslipidaemia during pregnancy, therefore expose the foetus to unfavourable intrauterine environment. Although maternal obesity and gestational hyperglycaemia have been associated with a series of adverse pregnancy outcomes in previous literature, lifestyle interventions during pregnancy do not confer significant benefit for composite maternal and neonatal health outcomes. Meanwhile, gestational dyslipidaemia has been recognised as an ignored metabolic risk factor for adverse pregnancy outcomes. Therefore, the aim of this project is 1) to explore the association between gestational dyslipidaemia and neonatal adverse metabolic conditions; 2) to establish the most influential maternal metabolic risk factors for maternal and neonatal adverse metabolic conditions; 3) to investigate the metabolic profile in babies with different birthweight percentiles. In this project, a comprehensive systematic review followed by a prospective cohort study and an exploratory study were conducted to address the above objectives. In summary, maternal lipid levels are secondary to maternal metabolic dysfunction with no clear causal links to adverse neonatal metabolic conditions, although it has strong associations with adverse birthweight outcomes. High maternal pre-pregnancy BMI is the most influential upstream metabolic risk factor for both maternal and neonatal metabolic health outcomes, therefore weight management should be addressed from the preconception period. The differential metabolic and inflammatory profile in small-for-gestational-age and large-for-gestational-age babies might be crucial for developing subsequent obesity, diabetes, and cardiovascular diseases. Tailored intervention strategies in babies with different birthweight percentiles are needed to prevent metabolic dysfunctions in adult life.

Obesity is currently widespread in the world; the epidemic and pathogenesis of the disease negatively affect several body systems including cardiovascular, endocrine and respiratory systems. Obesity influences the respiratory functions and this effect could be challenging for women, because the air way and lungs are smaller in women compared to men, as well as obesity itself exerts a negative mechanical effect on the women's airway. Since inflammation was proposed asthe main link between obesity and lung functions, a natural supplement like conjugated linoleic acid (CLA), which has been proposed as an antiinflammatory and anti-obesity food component, could be a potential supplement that can improve the lung functions in obese women. Therefore, the aim of this thesis is to explore the effect of CLA on obesity, lung function, adipokines and inflammation. Additionally, the effect of CLA on inflammation in the current thesis was explored using novel inflammatory markers, such as adhesion molecules (CD11b and CD62L) and heat shock proteins (HSPA1A and HSPB1). Investigating the evidence about the effect of CLA supplementation on obesity in women was conducted via a systematic review with meta-analysis. The meta- analysis searched randomised control trials (RCTs) supplemented CLA mixture in form of oral capsules for less than 6 months. Two search strategies were applied, and eight eligible trials were included with 330 women. CLA significantly reduced body weight (BW; 1.2±0.26 kg, p < 0.001), body mass index (BMI; 0.6 ±0.13 kg/ m², p < 0.001) and total body fat (TBF; 0.76± 0.26 kg, p=0.003) when it was supplemented for short durations (6- 16 weeks). Moreover, subgroups meta-analyses were conducted which were based on obesity level, menopausal age and life style of the participants. This meta-analysis suggested a mild anti-obesity effect of CLA. However, it was not clear whether the anti-obesity effect is enough to modulate obesity-induced inflammation and lung functions. Therefore, initially a crosssectional trial was conducted to assess the direct associations between the circulating level of CLA and obesity markers, lung functions and inflammations. To the best of Knowledge, this was the first cross-sectional trial that explored these direct associations. The cross-sectional trial recruited 77 women with average age 39 years old with forced expiratory volume in one-second (FEV1) ≥70%. The level of CLA in plasma was assessed by gas chromatography; the expression of the CD markers and HSPs were assessed using flow cytometry; body composition was assessed using bioelectric impedance; and lung functions were assessed using spirometer. Interestingly, the trial revealed significant positive associations between CLA and BW (R=0.4, p < 0.001), BMI (R=0.4, P < 0.001) and TBF (R=0.34, P < 0.001) in the overall population, and in perimenopause women. A significant inverse correlation between t10, c12-CLA and TBF was detected in overweight women (R=- 0.42, p < 0.05). A significant positive association (R=0.45, P < 0.04) was detected between the c9, t11-CLA and percentage peak of flow predicted (PEF %) in postmenopausal women, meanwhile t10, c12-CLA was negatively associated with peak of flow (R=-0.44, P < 0.04). CLA was inversely associated with adiponectin in both obese (R=-0.55, p < 0.1) and morbidly obese (R=0.48, P < 0.004) women. C9, t11-CLA was positively associated with the expression of HSPA1A inside the lymphocytes in postmenopausal women (R=0.58, p=0.04). HSPB1 expression in the monocytes were associated with both c9, t11-CLA (R=0.58, p < 0.05) and total CLA (R=0.71, p < 0.001). The level of expression of CD11b on the pro-inflammatory monocytes (CD14++ CD16+ ) was negatively associated with CLA (R=-0.36, p < 0.05). Ultimately, the study did not provide strong evidence regarding the direct relationship between CLA and obesity markers or lung functions. However, it showed a potential immunomodulatory effect of CLA on obesity-induced chronic inflammation, which subsequently could influence multiple obesity compilations. The lack of strong evidencewas primarily due to the nature of the study design (observational study). Therefore, in chapter 5 a randomised double-blind placebo control trial was conducted, for more powerful evidence based. The aim of the RCT was to look at the effect of 12-week CLA supplementation on obesity, lung function, adipokines and inflammation in obese and overweight women. The RCT recruited 56 overweight and obese women with a mean age of 42 years old, participants were randomly assigned either to receive 4.5gm/day of CLA or placebo (High Oleic Safflower oil). Participants had to attend three clinics at base line, after 6 weeks and after 12 weeks. In each clinic body composition, lung functions and inflammatory markers were assessed. The study revealed a significant 1.8% reduction in %BF in the CLA group compared to the baseline. No significant effect of CLA on the lung functions was detected, however, this study found a significant reduction in the expression of CD11b on the stimulated pro-inflammatory monocytes after 12 weeks compared to baseline in the CLA group. CLA caused a significant reduction in the expression of intracellular HSPA1A in PBMCs at week 12 compared to baseline. The results might suggest a limited anti-obesity effect of CLA, and a potential positive effect on obesity induced chronic inflammation. Ultimately, no evidence was demonstrated on the direct effect of CLA on lung functions or adipokines. The effect of CLA on adhesion molecules and HSPA1A could suggest an indirect impact on the lung function, but more research in clinically diagnosed patients with pulmonary dysfunctions could help to confirm the effect of CLA on the lung function and adipokines.

The research on which this thesis is based explores larger women's experience of 'maternal obesity'. My work takes a social constructionist approach to studying experience. This approach has been criticised for privileging the social aspects of embodiment at the expense of the more material, visceral aspects. My contribution addresses this criticism by adopting a novel narrative approach to the study of embodied experience. To do so I draw on writing from the fields of medical sociology, anthropology and bioethics, along with feminist and critical social perspectives to theorise the body as social, cultural, political and lived. At the heart of my work is the desire to examine, in detail, aspects of the 'moral jeopardy' (Murphy, 1999) which larger pregnant women have encountered in healthcare spaces and to explore the ways current obstetric approaches to 'maternal obesity' shape larger women's experiences of pregnant embodiment. By doing so, I make a contribution to knowledge about how the changing embodied experience of pregnancy is shaped by maternal healthcare practices in the context of maternal obesity discourse. The research is based on repeat in-depth interviews with six women who were medically classified as having 'maternal obesity'. The women were recruited from a single Scottish maternity hospital during the early stages of their pregnancies. The women's experience of pregnancy and childbirth was captured in three interviews over the course of their pregnancy and following childbirth. In order to gain a better understanding of the context in which the women received their care, individual face-to- face narrative interviews were also conducted with key maternal health professionals including five obstetricians, six midwives, and two anaesthetists. Data were analysed using a two-stage structural narrative analysis involving identifying how and why particular stories were told in the course of interviews, and exploring the broader narratives drawn on to make meaning in these stories. Following the work of sociolinguist Gee (1999, 2011), particular attention was paid to the ways that characters, situations, actions, and artefacts were framed in the stories. These framings revealed how participants understood their own actions, and those of others, in the context of their stories of experience. The research findings are presented as a series of composite monologues following the journey women travel through maternal healthcare - from the early stages of pregnancy through to the postnatal period. Presenting the findings in this way illuminates how the context of maternal healthcare configures pregnant embodiment as the pregnancy advances. Each monologue is accompanied by a commentary discussing the main analytical points, engaging with existing literature, and discussing the findings in light of what is known and the contribution made by this research. The findings reveal the complexities of maternal healthcare professional positionality in relation to the larger pregnant body, shaping the practice of these professionals with regard to larger embodiment. The findings further demonstrate that larger women's highly stigmatised and visible bodies render them vulnerable to targeted medical screening which also stigmatises the foetal body. Moreover, this process can serve to silence the women by rendering them somewhat (in)visible.

Background Obesity is a highly complex, chronic disorder with a multifactorial aetiology that includes biological, psychosocial and cultural factors. Since the discovery of oil in 1959, Libya has been undergoing a nutrition transition. Despite obesity reaching epidemic proportions in Libya, there is a lack of information about obesity in Libyan adults. Aims The aims of this study were to investigate the risks and protective factors associated with obesity among adult men and women in Libya; to estimate gender differences in the prevalence of obesity among Libyan adults; and to explore key informants’ views about obesity within the context of Libyan culture. Design of study An adapted mixed-methods sequential explanatory design was used, consisting of two phases: a quantitative study in the form of a cross-sectional design, and a qualitative study in the form of semi-structured interviews, which followed up on the findings of the first phase. Method A multi-stage cluster sampling technique was used to select participants from the Benghazi electoral register. With a response rate of 78%, the sample consisted of 401 Libyan adults, aged 20-65 years, who have lived in Benghazi for over ten years; 63% were female. A survey questionnaire was used to examine the relationship between Body Mass Index (BMI) and the following four-predictor variables, derived from the Socio-Ecological Model (SEM): socioeconomic status; unhealthy eating habits; physical activities and sedentary lifestyle; and neighbourhood environment. Anthropometric measurements were collected from participants in their homes. For the qualitative phase, 9 Libyan healthcare professionals and 12 Libyan community leaders (key informants) were individually interviewed. A mixed-methods approach to study obesity has not previously been used in Libya. Results The prevalence of obesity among Libyan adults was found to be 42.4%, whereas that of being overweight was 32.9%. A significant positive association was found between obesity and two SES components (education level and income) in Libyan adults of both genders, while occupational status was significantly positively associated with obesity in women only. Obesity was significantly positively associated with fast-food consumption, and the consumption of large food portion sizes, in Libyan adults of both genders. In contrast, the consumption of sugar-sweetened beverages was significantly positively associated with obesity in Libyan women but not in men. A significant inverse association was found between breakfast consumption and obesity in Libyan adults. Obesity was significantly negatively associated with physical activity in Libyan women, while significantly positively associated with sedentary behaviour in Libyan women but not in Libyan men. Finally, a significant association exists between the BMI of Libyan adults in 6 of the 12 neighbourhood environment attributes. For Libyan men and women these were: street connectivity, ‘unsafe environment and committing crimes at night’, and neighbourhood aesthetics. For men only, these were: access to public transport, access to recreational facilities, and ‘unsafe environment and committing crimes during the day’. Finally, ‘residential density zones’ was significant for women but not for men. Three main risk factors were identified from the qualitative study. The first concerned the heavy subsidisation of staple food commodities in Libya; the second is Libya’s deteriorating health sector performance; and the third is the effect of the neighbourhood environment on physical activity and food, including the current political and economic instability in Benghazi which is potentially fuelling the obesity epidemic. These themes and additional sub-themes were categorised as belonging to one of the five spheres of the SEM (individual; interpersonal; institutional and organisational; community and physical environment; and public policy), resulting in the final conceptual framework of this study. Some of the qualitative results contradicted the quantitative results, resulting in some inconclusive findings. Conclusion These findings could inform Libyan health policies and the interventions that are urgently needed for preventing or controlling the obesity epidemic in Libya. Key recommendations are that an electronic health information system needs to be implemented and awareness about obesity and its causes and consequences needs to be raised among the public in order to dispel the many myths and misconceptions held by Libyans about obesity.

Background: Obesity prevalence in Mexico has risen substantially over the last 25 years. Its social patterning has not been systematically studied. Aim: To test the nutrition transition proposition of a crossover from lower to higher rates of obesity among the more disadvantaged groups, leading to emerging and increasing obesity inequalities as Mexico develops economically. Methods: Data came from four nationally representative surveys (1988, 1999, 2006, 2012); N=51,387 non-pregnant 20-49 year old women and N=18,988 20-49 year old men. Level of education and a household wealth index were used to calculate the relative and slope indexes of inequality (RII and SII respectively). Trends in RII and SII were examined in the period 1988-2012 for women. Change from 2006 to 2012 was examined for men. The contribution of mediating factors to obesity inequality was investigated. Results: There was support for the nutrition transition proposition among Mexican women. As the country developed economically, obesity became more prevalent among more disadvantaged women. Among men, there was no evidence of a reversal of the social gradient. Higher education and wealth were associated with higher obesity prevalence. Unexpectedly, educational inequalities in obesity among urban women declined over the study period. This was due to faster increases in obesity prevalence among women with more years in education compared to those with less. Psychosocial factors (food insecurity and aspired body size) explained a proportion of educational inequalities in obesity among women. Gender differences in educational inequalities in obesity were partially explained by differences in aspired body size. Conclusion: This detailed analysis of obesity inequalities in Mexico, and their recent trends, significantly develops existing literature. By using both education and household wealth as markers of SEP, the nutrition transition proposition was investigated in depth. The nutrition transition proposition fits the educational inequality pattern among Mexican women but not men.

The focus of this thesis was to investigate, especially in the context of obesity, the interactions among sleep duration and quality, and adverse health outcomes. Three comprehensive studies are described in the thesis: 1. A cross-sectional epidemiological study examined factors that are associated with both short and long sleep duration among an older Chinese population, and also assessed whether there was a link between sleep duration and chronic conditions such as obesity, hypertension, and diabetes. This study showed that long sleep duration was associated with increased risk for obesity among women. Additionally, demographic, socio-economic, and medical conditions were associated with sleep duration. Identifying potential factors that affect sleep will inform future interventions for improving sleep with potential downstream effect on obesity and other chronic disorders. 2. A cross-sectional study of patients with extreme obesity indicated that the prevalence of sleep disturbance is high in this patient population. There was a positive association between sleep disturbance factors and depressive symptoms and quality of life among these individuals. The findings emphasise the importance of adequate assessment and treatment of sleep problems in this patient population. 3. A systematic review and meta-analysis assessed the effectiveness of lifestyle modification interventions on the treatment of obstructive sleep apnoea (OSA). Lifestyle interventions such as dietary and physical activity improved OSA parameters, but were insufficient to normalise them. The findings will inform the development of future interventions for OSA, and are likely to contribute to clinical guidelines for OSA management.

Public health still needs to better understand how older people’s life circumstances influence key risk factors for chronic disease, and also how women and men differ in their exposures and outcomes. This dissertation aimed to examine, separately for women and men, the role and inter-relationships of factors describing the economic and social contexts in relation to healthful eating and adiposity. A systematic review of economic determinants of diet in the elderly indicated that longitudinal evidence remains limited and focused on employment-related changes affecting diet. Thus, novel economic variables concerning financial hardship (FH) were examined in over-50s from the population-based EPIC-Norfolk cohort for associations with quantity and variety of fruit and vegetable intake, as proxies for healthful eating. FH was inversely associated with variety, more than quantity, independent of socioeconomic status (SES). Given the importance of social contexts for diet, it was notable that three aspects of structural social relationships were each associated with variety differently for women and men and, when combined, differed across categories of a second social tie. The next study of EPIC data investigated inter-relations between multiple economic variables, including FH, and social ties, demonstrating a magnification of unit differences in variety when economic and social disadvantage occurred simultaneously. Obesity is another chronic disease risk factor with known social gradients; thus a fourth study in EPIC examined associations of FH and SES with objectively measured obesity. All three FH measures were independently associated with general and central obesity, with the strongest relationships between greatest level of difficulty paying bills and central obesity in women, and general obesity in men. Finally, a longitudinal study of civil servants (Whitehall II) showed a strong association of persistent FH with 11-year adjusted mean weight change, and excess gain, in women only, which was not explained by any of the six potential mechanisms examined in mediation analyses. In sum, everyday financial troubles constituted a unique economic influence on diet quality and obesity in older adults, and the influence of a given economic or social factor on diet quality was modified when another social factor was also considered. Unique aspects of economic or social circumstances, and their different combinations, must be considered separately in future public health research and practice as each reflects a distinct process of social differentiation and hence adds to our understanding of contextual influences on chronic disease risk factors.

Introduction: The prevalence of obesity within countries varies by gender, age, socioeconomic status, and culture. These determinants appear to predict obesity differently in different countries. The objective of this study was to estimate the impact of these determinants on obesity in a representative sample of the Lebanese adult population. Methods: A cross-sectional survey of 2697 adults aged ≥ 20 years, excluding pregnant and lactating women, was conducted in 2008. Households were selected randomly from all Governates of Lebanon based on a stratified cluster sampling. One randomly-sampled adult was interviewed in each visited household; demographic, socioeconomic and anthropometric data were measured. Dietary intake was obtained using a 24-hour recall instrument. The prevalence of obesity in 2008 was estimated. Logistic regressions analysis was carried out to assess the relationship between energy intake and obesity as well as adjusted relevant variables, excluding data from participants who reported implausible energy intakes. Results: Currently, approximately one in four Lebanese adults is obese. While men and women showed overall similar prevalence rates of obesity, gender disparities were noted across obesity classes and age groups. In males, the odds of being obese increased among those married, employed, and owning increased household assets; the opposite was the case for women. Obesity in women decreased with increasing household wealth. In women also, there was a positive association between obesity and energy intake, and a negative association between obesity and physical activity. Obese adults reported consuming a higher percentage of their energy intake from fat, and a lower intake from cereals, compared with their non-obese counterparts. Conclusion: The prevalence of obesity among Lebanese adults is on the rise, with significant demographic and socioeconomic differentials. High energy consumption and inactivity of Lebanese adults, as well as several complex socioeconomic and cultural elements, are contributing factors to the estimated high rates of obesity.

Aim: The aim of the thesis was to identify how resources, developed in childhood, could help overcome adversity in adult life.;Methods: The analysed data came from the National Child Development Study. Resources were indicated by externalizing and internalizing symptoms, reading, mathematics and BMI. Operationalization of the resources was conducted using data measured at a single time point and group based developmental trajectories identified by mixture models. Associations between the developmental trajectories and birthweight, preterm birth and parental social class were tested in order to identify the trajectories' origins at birth. A source of adversity was indicated by unemployment. Logistic regression was used to test if the resources could protect people from experiencing unemployment. Statistical interactions between unemployment and resources in the prediction of health consequences were used to test for resilience to the consequences of experienced unemployment. Health consequences were assessed by self rated health, limiting longstanding illness, Malaise, GHQ and weight change.;Results and conclusions: For both genders, group based developmental trajectories provided a reasonable summary of the data for externalizing symptoms, reading and mathematical ability and BMI. Parental social class was associated with all the disadvantaged developmental trajectories. Low birthweight and preterm birth were associated with disadvantaged emotional and cognitive development, and high birthweight was associated with trajectories that contained individuals who had a high BMI throughout childhood but did not develop adult obesity. For women, the associations between unemployment and health consequences were limited. The only indicator of (lack of) resources associated with unemployment was internalizing symptoms. For men, unemployment represented a challenge to health, all the resources protected men from experiencing unemployment, and reading skills and internalizing symptoms indicated resilience to the health consequences of unemployment. The theoretical and methodological issues raised by the use of developmental trajectories and traditional methods are discussed.