The nutrition transition associated with economic development and rapid urbanisation in Thailand has led to increasing incidence of overnutrition in some segments of the population. This has been attributed to significant shifts in dietary intake patterns characterised by an increase in the fat density of energy intakes and excessive sugar consumption. Given that overnutrition is a proximate cause of obesity and several chronic diseases, the promotion of healthier dietary patterns has become an important concern for public health policy. In the first part of the thesis, we investigate the determinants of overnutrition and compare the differential effects of these determinants between the predominantly urbanised central region and the less urbanised northeast region in Thailand. With data from the Thai Food Consumption Survey, we use quantile regressions and counterfactual decompositions to decompose the differences between the two regions into "covariate" effects and "co-efficient" effects. We find that income growth is not a key factor driving overnutrition. Urban location, higher socio-economic status and female gender are associated with high fat density diets. Our counterfactual decomposition exercise suggests that coefficient effects are predominant which suggests that even if the northeast region were to acquire the socio-demographic characteristics of the central region, large differences in the fat density of diets would persist, particularly in the lower quantiles of the intake distribution. This highlights the role of environmental, social and cultural factors in explaining the differences in dietary patterns between the two regions. The increased consumption of sugar-sweetened beverages (SSBs) has been identified as a key driver of excessive sugar consumption in Thailand. A tax leading to 10% increase in price of SSBs has been suggested by the WHO and other agencies to reduce sugar consumption. In the second part of the thesis, we estimate a dynamic demand model to examine the potential impact of the proposed tax on non-alcoholic beverages consumption in different segments of the population. In the absence of panel data, we construct pseudo-panels from repeated cross-sections of the Thai Socio-Economic Surveys for empirical estimation.

Higher food prices, dwindling purchasing power and socio-economic inequalities are crucial factors promoting under-nutrition in Nigeria. Previous efforts to enhance food consumption and nutrition achieved limited successes as most of the interventions focused largely on food supply with little detailed appraisal of drivers of food demand, especially at the household level. Consequently, this study examines the structure of food demand among households with emphasis on price and income as key variables on which interventions can be built to boost food consumption and nutrition. The study utilises the Nigeria Living Standard Survey and the food price data for 2003/2004 from the National Bureau of Statistics, Nigeria for analyses while employing the double-hurdle model, nutrient deficiency index and a pro-undernourished policy index as analytical tools. A Bayesian (Gibbs sampler) approach is used to estimate the almost ideal demand system (AIDS) model within the framework of the multivariate double-hurdle model. The ensuing demand elasticities indicate food demand patterns characterised by substitutability and complementarity relationships among food subgroups. Approximately 3.99 million people in Nigeria could have been pushed into hunger and calorific under-nutrition as a result of the recent global food price crises. Higher per capita food consumption and accelerated attainment of the Millennium Development Goals on nutrition can be achieved in Nigeria if future economic growth is accompanied by pro-poor income redistribution strategies. A universal transfer strategy or a targeting mechanism with broader scope than the child targeting mechanism being used under the existing conditional cash transfer scheme might be more efficient in reducing under-nutrition among poor households in Nigeria. Although the results suggest that a food stamp scheme would be more cost-effective in raising food consumption and nutrition among the neediest household groups in the country than a cash transfer intervention, its introduction should be considered with some circumspection.

The United Kingdom (UK) has one of the highest obesity levels in the world (Mazzocchi, Traill and Shogren, 2009). As indicated by the National Health Service (2010), 25% of adults and 17% of children are obese in the UK. This last statistic represents an increase of four points in comparison to 1995. The Government Office for Science (2010) estimated that by 2050, half of the UK population would be obese, with a consequent direct annual cost of £ 1 0 billion and an indirect annual cost of £50 billion at today's prices. Governments have the role of ensuring that households have the most complete information possible about their food choices (Mazzocchi, Traill and Shogren, 2009). With this objective, the UK government has conducted information campaigns such as nutritional food labelling and the 'Change 4 Life' campaign, in order to increase nutritional awareness. Despite government efforts, obesity has been steadily increasing in the UK. This research aims to contribute to the debate on how health-related information impacts household food expenditure and whether this impact varies across income groups and household composition. This study specifically measures the impact of child obesity news on household food expenditure in the UK. To this end, the study calculated a set of elasticities for different income groups (high vs. low) and family composition (families with and without children). This set of elasticities gives us a measure of responsiveness, to change in terms of price, income and news. This study uses an augmented two-stage budgeting demand system. Demand systems combine price, income and news index data into a well-supported economic framework. The empirical analysis includes testing for homogeneity, symmetry, concavity and the time series properties of the data and the residuals. In the UK, no recent study has measured the impact of news on household food expenditure. Moreover, few empirical demand studies use structural approaches that are consistent with the time series properties of the data.

Sub-Saharan Africa is projected to be severely affected by climate change in the form of increased climate variability. Ghana provides a suitable case study country in which to assess the vulnerability of communities to such climate changes. Data on the nature and extent of vulnerability of Ghana’s food production systems and livelihoods to climate variability (particularly drought) are lacking, and this hampers the development of effective policy to reduce the adverse impacts of climate change and variability. This study aims to enhance empirical understanding of the socioeconomic, institutional and biophysical factors that contribute to vulnerability to climate change and variability amongst a range of farming households and communities in Ghana. By integrating statistical analyses, participatory methods and ecological surveys, this research adopts a multi-scale approach to assess the extent of food production and livelihood vulnerability across multiple scales: mapping vulnerability at the national and regional scales and drilling down to the community and household scales. Results show that the vulnerability of crop production to climate variability (particularly drought) has discernible geographical and socioeconomic patterns, with the Northern, Upper West and Upper East regions being most vulnerable. The results of the drought assessment are used to guide local-level research, and demonstrate the need for region-specific policies to reduce vulnerability and enhance drought preparedness within dryland farming communities. Within the same agro-ecological setting, different communities and households experience different vulnerability attributed to differences in socioeconomic characteristics. Results show that vulnerability of farming households can be linked to access to livelihood capital assets and that vulnerable communities tend to have households that are characterised by low levels of human, natural, financial, physical and social capitals. Findings also demonstrate that small-scale farmers employ a range of on-farm and off-farm adaptation strategies including changing the timing of planting, planting of drought-tolerant and early maturing varieties of crops, livelihood diversification, agro-forestry systems, crop diversification, temporary migration, relying on social networks and reducing food consumption to manage climate variability. A range of challenges including a lack of financial resources, poor access to information on climate adaptation, complex land tenure systems, social-cultural barriers, limited access to improved varieties of crops, as well as a lack of institutional support, constitute serious barriers to adaptation. Policy makers need to formulate specific and targeted climate adaptation policies that a) enable farmers to engage in alternative livelihood diversification strategies; b) promote the development and planting of improved varieties of crops; and c) allow for the provision of institutional support including access to information on climate adaptation and adequate all-year-round extension services. Such policies should be linked to programmes that foster asset building as well as enhance institutional capacity and social capital.

This thesis explores employment among people who inject drugs (IDU). It seeks identify what differentiates IDU who work from those who do not, barriers to labour market participation, and how employment is perceived and experienced by IDU. Using longitudinal data from the Vancouver Injection Drug User Study (VIDUS), it conducts this research through a detailed examination of the implications of missing data, quantitative analyses of transitions into employment and qualitative, in-depth interviews. Missing data analyses identified differences between those that those that do and do not have missing data, as well as predictors of observation gaps and how individuals end their study participation (either right-hand censorship, attrition, or death). Differences were observed along individual, behavioural and contextual dimensions. Analytical approaches to the relationship between data structure and content gleaned useful information for longitudinal studies with marginalized populations. Discrete time event history analyses of work transitions revealed complex relationships between drug use, drug-related activities, situational risk factors, and transitions into employment. While most IDU did not make transitions into employment, some did, and while some statistical relationships were expected, others were surprising. Novel findings included mode-specific addiction treatment impacts on employment (methadone vs. non-methadone) and the importance of the broader risk environment over and above even high-intensity substance use. Finally, qualitative interviews identified heterogeneity in individual motivations toward and experiences of work. Those who maintained concurrent drug use and formal labour market involvement utilized strategies to spatially and temporally separate the two activities. Individual capacities to employ these strategies were facilitated by material, vocational and temporal motivations, and interfered with by health conditions, catastrophic events and institutional relationships that operated as barriers to employment. This study provides insight into what is a known social determinant of health in the general population among injection drug users.

Les produits traditionnels semblent être une « nouvelle » tendance pour les produits alimentaires. De nombreux travaux sont effectués pour définir ce qu’est le produit traditionnel. Cependant, nous observons par la littérature en sciences de gestion que le produit traditionnel alimentaire est un concept flou, qui manque de précision. D’ailleurs, nous ne pouvons pas savoir avec précision ce que le consommateur perçoit comme traditionnel dans un produit alimentaire. Dans l’optique d’apporter une vision différente, nous nous intéressons à comprendre les éléments traditionnels perçus dans le produit alimentaire. Nous mobilisons une revue de littérature en sciences sociales afin d’apporter de la clarté et structurer la traditionnalité perçue d’un produit alimentaire. Notre collecte de données utilise plusieurs méthodes qualitatives. Pour donner une nouvelle vision de ce qui est perçu comme traditionnel, nous faisons l’analyse à l’aide de la Grounded Theory. Avec les résultats de cette analyse, nous proposons quatre dimensions de la traditionnalité. Nous réalisons une triangulation méthodologique des données par une analyse statistique de données textuelles. Nos résultats sont concluants. La traditionnalité perçue d’un produit alimentaire est un concept expérientiel, à quatre dimensions : processuelle, dynamique, identitaire et rituelle. Cette conceptualisation apporte de la clarté en termes théoriques. Elle ouvre de voies pour le développement des outils de mesure. En termes managériales, la mise en évidence de la traditionnalité perçue d’un produit alimentaire et l’expérience de consommation ou d’élaboration offre des possibilités de développement aux producteurs. / Traditional food products seem to be a "new" trend. A lot of work has been done to define what is a traditional product. However, we observe from the literature review in management that traditional food product is a fuzzy concept, which lacks of precision. Besides we can not know precisely what the consumer perceives as raditional in food product. In order to provide a different point of view, we are interested in understanding the traditional elements perceived in the food product. We mobilize a literature review in the social sciences in order to bring clarity and structure to perceived traditionality of food product. Our data collection uses several qualitative methods. To give a new vision of what is perceived as traditional, we make an analysis using the Grounded Theory. Through the results of this analysis, we propose four dimensions of traditionality. We perform a methodological triangulation of the data by statistical analysis of textual data. Our results are conclusive. The perceived traditionality of a food product is an experiential concept, with four dimensions: process, dynamics, identity and ritual. This structuring brings clarity in theoretical terms. It opens up ways for the development of measurement tools. In managerial terms, the highlighting of the perceived traditionality of a food product and the elaboration or consumer experience offers development opportunities to producers.

L’objectif de cette thèse est de concevoir une démarche d’intervention pour promouvoir la réduction du gaspillage alimentaire reposant sur l’hypocrisie induite semble. Cette procédure d’induction de dissonance articule une phase de saillance normative et une phase de rappel des transgressions. Si l’hypocrisie induite est interprétée à la lumière de la théorie de la consistance de Soi, nous reprenons à notre compte les propos de Vallacher (1992), selon lesquelles la nature de l’action, c’est-à-dire les significations qu’un individu attribue à ces comportements, est susceptible d’influencer le processus de dissonance. La théorie des niveaux de construit, incluant l’identification de l’action, a été mobilisée pour appréhender les significations accordées à des conduites pro-sociales. Plus précisément, nous avons examiné l’influence des niveaux de construit, sur les comportements de soumission obtenus, selon que la phase de saillance normative sera suivie ou non d’un rappel des transgressions. Dans une première expérience, nous avons testé l’applicabilité de l’hypocrisie induite pour promouvoir la réduction du gaspillage alimentaire. Les deux expériences suivantes examinent l’influence des niveaux de construits dans l’hypocrisie induite. Enfin, une recherche-action reposant sur des interventions de type face-à-face auprès des ménages a été mise en œuvre et integre des mesures comportementales effectives. Nos résultats suggèrent que l’hypocrisie induite est à même de promouvoir des changements de comportements effectifs de réduction du gaspillage, mais que ces changements dépendent des significations accordées à cette conduite pro-sociale / Our research aims at conceiving an intervention process to promote food waste reduction in households. Considering the characteristics of food waste, induced hypocrisy appeared adapted to lead to behavioural changes. This sequential procedure of dissonance induction articulates two steps: preaching publicly a socially desirable behaviour (normative salience) and remembering one’s counter-normative behaviours (mindfulness). Though induced hyprocrisy is interpreted in the light of self-consistency theory, we make ours Vallacher’s propositions (1992), according to which the nature of the action, that is the meanings attributed to these behaviours by an individual, is likely to influence arousal and dissonance reduction. This research relies on construal level theory, including action identification, to understand the meanings given to pro-social behaviours. More specifically, we tested the influence of construal levels, manipulated during the stage of normative salience, on the compliance behaviours thus obtained, whether the normative salience stage be or not followed by mindfulness. In a first study, we applied induced hypocrisy to a previously unstudied behavioural area: the encouragement of food waste reduction. The next two experiments, conducted in a laboratory, examined the influence of construal levels in induced hypocrisy. Relying on these studies, we conducted a field experiment, which used effective behavioural measures, based on face-to-face interventions in the households. Our results suggest that induced hypocrisy may encourage individuals to actually reduce food waste, but that these changes depend on the meanings they grant to this pro-social behaviour

Achieving food security under climate change is one of the biggest challenges of the 21st century. The challenge becomes even greater when contextualised within our current limited understanding of how the food system functions as a complex, adaptive socio-ecological system, with food security as one of its outcomes. Adding climate change into this already complex and uncertain mix creates a ‘wicked problem’ that must be solved through the development of adaptive food governance. The thesis has 4 key aims: <ul><li>1. To move beyond an understanding of food security that is dependent solely on agricultural production, and therefore the reliance of future food security predictions on production data based on climate model inputs.</li><li>2. To ground the theoretical aspects of complex adaptive systems with empirical data from multi-level case studies.</li><li>3. To investigate the potential role of the private sector in food system futures.</li><li>4. To analyse food system dynamics across scales and levels.</li></ul> In order to realise these aims, a complex adaptive system (CAS) approach within the GECAFS food system framework is employed to multilevel case studies in South Africa and Brazil. Particular emphasis is placed on the role of the private sector and how these vital actors, comprising a powerful component of the global food system, can be mobilized towards building adaptive capacity for a more resilient food system. Critically, the private sector is often left out of academic discussions on adaptation, which tend to focus more on civil society and governmental capacity to adapt. This thesis provides novel insight into how the power of the private sector can be harnessed to build adaptive capacity. The findings of the thesis showed that applying CAS to issues of governance has three important implications: The first is that in a complex system, it is critical to maintain diversity. This can translate into appreciating a multiplicity of viewpoints in order to reflect a range of decision-making options. This finding makes the case for closer synergy between the public and private sectors around areas like product development and distribution that includes an emphasis on enhancing food security under climate change. In the developing country context, the inclusion of smallholders and local entrepreneurs is also vital for building adaptive capacity. In this sense, it is possible for business to help achieve development goals by developing the capacity of those most vulnerable to socio-economic and environmental shocks. Secondly, adapting to climate change and other environmental and economic pressures will require a shift in mind-set that embraces the uncertainty of the future: ‘managing for uncertainty rather than against it’. This entails a shift in governance mindset away from linear thinking to a decision-making paradigm that is more flexible to deal with unexpected shocks. The third implication for governance is the need to understand the complex interplay of multiple interlinking processes and drivers that function across many levels and sometimes have exponential positive feedbacks in the food system. Adaptive governance is an iterative process, but as more is learnt and information is retained in the system, the ideal is that the beneficial processes that lower inequality and increase food security will start to be reinforced over those that entrench the current inequality in the food system.