O alimento é uma importante fonte de prazer para os seres humanos. No entanto, ao longo dos anos, sacrificar este prazer vem caracterizando um dos comportamentos mais autorregulares da sociedade contemporânea - a prática de dietas de emagrecimento. Nesta tese, propõe-se a existência de vulnerabilidades que não foram contempladas nos modelos de bem-estar alimentar (originalmente conhecido por, Food well-being - FWB) desenvolvidos por Block et al. (2011) e por Bublitz et al (2012). Neste sentido, a presente tese possui um caráter inovador, dada a inexistência de estudos que relacionem o construto \'bem-estar alimentar\' com a \'vulnerabilidade\' do consumidor, diante de um contexto de comportamento alimentar associado à prática de dietas. À luz do exposto, buscou-se responder a pergunta central: Como o comportamento alimentar associado à prática de dietas pode influenciar o bem-estar alimentar? Para tanto, adotou-se a perspectiva do FWB, inserida no contexto da Pesquisa Transformativa do Consumidor (TCR). Por meio de uma pesquisa qualitativa básica de caráter interpretativista, entrevistas com dezesseis mulheres foram realizadas. Além das entrevistas, analisaram-se duzentas e uma fotos por meio da técnica de foto-elicitação. A interpretação dos dados foi realizada a partir da análise temática das falas e análise do conteúdo das fotos, respectivamente. Os resultados indicaram que apesar das informantes expressarem sentimentos de prazer relacionados à comida, existe uma dicotomia ao levarem em consideração a possibilidade de aumentarem seu peso. Além disso, foi possível identificar algumas vulnerabilidades decorrentes tanto de fatores externos como de características e fatores pessoais, quais sejam: o preço alto dos produtos relacionados à dieta; desconhecimento e dificuldades para distinguir os alimentos (principalmente frutas, verduras e legumes) caso estejam sem a devida identificação; entender os aspectos nutricionais dos alimentos para se realizar uma boa escolha e as divergências nos discursos do mercado e dos profissionais em relação ao que é um alimento \'saudável\' ou \'não saudável\'. Cabe ressaltar, que nas sete dimensões do FWB, as informantes experienciaram vulnerabilidades. Acredita-se que o bem-estar alimentar pode ser atingido pelos indivíduos que praticam dieta para emagrecimento, quando uma relação psicológica, física, emocional e social positiva com os alimentos for estabelecida, e quando as vulnerabilidades associadas a este contexto forem minimizadas. / Food is an important source of pleasure for humans. However, over the years, sacrificing this pleasure has been characterizing one of the most self-regulating behaviors of contemporary society - the practice of dieting. In this thesis, it is proposed the existence of vulnerabilities that were not included in the well-being models (originally known as the Food Well-Being (FWB) developed by Block et al. (2011) and by Bublitz et al (2012). In this sense, this thesis has an innovative character, given the inexistence of studies that relate the construct \'food welfare\' to the \'vulnerability\' of the consumer, in the context of dietary behavior associated to the practice of diets. In the light of the above, we sought to answer the central question: How can dietary behavior associated with dietary practices influence dietary well-being? For that, the FWB perspective, inserted in the context of the Transformative Consumer Survey (TCR), was adopted. Through a basic qualitative research of interpretative character, interviews with sixteen women were performed. In addition to the interviews, two hundred and one photos were analyzed through the technique of photo-elicitation. The interpretation of the data was done from the thematic analysis of the speeches and analysis of the content of the photos, respectively. The results indicated that although informants expressed feelings of pleasure related to food, there is a dichotomy in taking into account the possibility of increasing their weight. In addition, it was possible to identify some vulnerabilities due to external factors as well as personal characteristics and factors, such as: the high price of products related to the diet; lack of knowledge and difficulties in distinguishing foods (especially fruits, vegetables and vegetables) if they are not properly identified; understand the nutritional aspects of food to make a good choice and the differences in the market and professional discourses about what is \'healthy\' or \'unhealthy\' food. It should be noted that in the seven dimensions of the FWB, the informants experienced vulnerabilities. It is believed that dietary well-being can be achieved by individuals on a weight-loss diet when a positive psychological, physical, emotional, and social relationship with food is established, and when the associated vulnerabilities in this context are minimized

Ancrée dans le courant de la Transformative Consumer Research (Mick et al., 2012), cette recherche explore la manifestation du bien-être alimentaire à partir de l’analyse de souvenirs d’expériences vécues par le consommateur. Dans une approche naturaliste (Lincoln et Guba, 1985) et interprétativiste, notre recherche qualitative combine trois types de recueil de données pour accéder aux expériences vécues des consommateurs : l’entretien phénoménologique, la photo-élicitation et le journal personnel. En suivant un processus d’analyse fondé sur la Grounded Theory (Glaser et Strauss, 1967), nos résultats présentent deux éléments majeurs de l’expérience de bien-être alimentaire : le rôle de l’expression des valeurs personnelles (Schwartz, 1992) dans l’expérience de bien-être alimentaire et l’existence de trois composantes-clés dans le processus global de l’expérience. Les résultats nous permettent alors de définir l’expérience de bien-être alimentaire comme une expérience eudémonique, congruente avec les valeurs ou types motivationnels de la personne. Elle est soutenue par différentes conditions facilitantes (attention portée au temps qualitatif, aux produits et recettes ainsi qu’au contexte physique de l’expérience) ; elle implique différents processus expérientiels (pleine maîtrise de l’expérience, immersion, initiation, partage, réminiscence et reproduction du souvenir et processus sensoriel) ; enfin, elle fait émerger des résultantes émotionnelles positives pouvant se combiner (fierté, joie, enthousiasme, gratitude, détente, réconfort et nostalgie). Nos résultats nous conduisent à proposer une taxonomie du bien-être alimentaire selon quatre types : le bien-être alimentaire de conservatisme, de transcendance de soi, d’ouverture au changement et d’affirmation de soi. Ils mettent au jour la définition d’eudémonie alimentaire qui caractérise l’alignement des expériences alimentaires et des significations attribuées au bien-être sur les propres valeurs de l’individu. Enfin, cette recherche propose des recommandations managériales en direction des pouvoirs publics, des associations de défense des consommateurs et organisations non gouvernementales ainsi qu’à tous les acteurs des filières alimentaires et distributeurs investis et/ou concernés par la question du bien-être du consommateur. / Rooted in the Transformative Consumer Research (Mick et al., 2012), this research explores the manifestation of food well-being using consumers' memories of lived experiences.  In a naturalistic (Lincoln and Guba, 1985) and interpretativist approach, this qualitative research combines three types of data which grant us access to lived experiences: the phenomenological interview, photo-elicitation and the personal diary. By following a grounded analysis process theory (Glaser and Strauss, 1967), our results present two major elements defining the experience of food well-being: the role of the expression of personal values (Schwartz, 1992) in the experience of food well-being and the presence of three key components in the overall process of the experiment. The results then allow us to define the experience of food well-being as a eudemonic experience linked to the motivational values of the person. This is supported by different enabling conditions (attention to quality of time, products and recipes as well as the physical context of the experience); experiential processes (full mastery of the experience, immersion, initiation, sharing, reminiscence and reproduction of memory, and sensory process); and positive emotions (pride, joy, enthusiasm, gratitude, relaxation, comfort and nostalgia). Our results propose a taxonomy of food well-being according to 4 principles: the food well-being of conservation, the food well-being of self-transcendence, the food well-being of openness to change and the food well-being of self-enhancement. These concepts define food eudemonia characterized by the confluence of food related experiences and meanings attributed to well-being with the individual's own values. Finally, this research proposes managerial recommendations for public authorities, consumer protection associations and non-governmental organizations, as well as all the actors in food chains and distributors invested and / or concerned by consumer well-being issues.