L'influence de l'étiquetage nutritionnel sur les sensations d'appétit et les attitudes à l'égard des aliments

Dans un contexte où les taux d’obésité et de maladies cardiovasculaires sont en constante augmentation, l’étiquetage nutritionnel est identifié comme stratégie pour l’amélioration des habitudes alimentaires. Alors que le lien entre l’étiquetage nutritionnel et l’apport alimentaire a été beaucoup étudié dans les dernières décennies, l’impact sur les sensations d’appétit est moins documenté. Par ailleurs, le lien entre les étiquettes nutritionnelles et les perceptions à l’égard des aliments fait l’objet de résultats très divergents dans la littérature. Les résultats présentés dans ce mémoire mettent en lumière l’importance de s’attarder à cette problématique. La présence d’une allégation concernant le contenu en gras du repas semble diminuer la sensation de faim davantage que l’affichage du contenu calorique, particulièrement chez les femmes obèses. Par ailleurs, chez les femmes de tous poids, l’appréciation des repas semble influencer la relation entre les étiquettes et les sensations d’appétit. En somme, ces résultats suggèrent que l’étiquetage nutritionnel puisse influencer les sensations perçues par les consommateurs en modifiant leurs perceptions des aliments.Nutritional labeling is one of the national and worldwide strategies to improve eating habits, especially in a context where the prevalence of obesity and cardiovascular diseases is steadily increasing. While the association between nutritional labeling and food intake has been studied extensively in the last decades, the impact on appetite sensations is much less documented in the scientific literature. Moreover, the association between nutritional labels and food perceptions is subject to a variety of results in the literature. The results presented in this paper highlight the importance of addressing these issues. The meals with a low-fat label were perceived as more satiating than the meals with the calorie label, mainly among obese women. Moreover, differences in appetite sensations were observed according to the degree of meals’ appreciation among both normal-weight and obese women. In conclusion, those results suggest that nutritional labeling may influence consumers’ perceived sensations by altering their perceptions of food

Analyse des déterminants de l'adhésion à la saine alimentation chez les Québécois

Les évidences au sujet du rôle de la saine alimentation dans la prévention des maladies chroniques sont sans équivoque. Cependant, les Québécois peinent à atteindre les recommandations nationales en matière de saine alimentation. De nombreux facteurs relatifs à l’individu, à l’environnement social et à l’environnement alimentaire physique peuvent influencer les choix alimentaires. Jusqu’à présent, les déterminants de la saine alimentation ont été très peu étudiés au Canada. De plus, les études ayant identifié des déterminants de la saine alimentation ont souvent utilisé des outils de mesure non validés. Le premier objectif général de mes travaux de doctorat était de développer des questionnaires spécifiquement conçus pour les adultes québécois et de procéder à leur validation. Pour ce faire, des questionnaires portant sur l’appréciation des aliments « camelote », le soutien des proches pour manger sainement et la perception de l’environnement alimentaire ont été développés. Dans le cadre d’une étude de validation, 75 femmes et 75hommes ont rempli les questionnaires à deux reprises sur une plateforme web. Les questionnaires développés ont démontré leur validité et fiabilité à la suite d’un processus de validation en plusieurs étapes. Le deuxième objectif général de cette thèse était d’identifier des déterminants, relatifs à l’individu, à l’environnement social et à l’environnement physique, associés à l’adhésion aux recommandations du guide alimentaire canadien (GAC) 2007, en vigueur au moment de l’étude, chez les adultes québécois et d’investiguer des interactions possibles entre les différents déterminants. Cet objectif a été atteint dans le contexte de l’étude PREDISE (PREDicteurs Individuels, Sociaux et Environnementaux de la saine alimentation), pour laquelle un échantillon composé de 1200 Québécois francophones âgés de 18 à 65 ans a été recruté. Les participants provenaient de cinq régions du Québec (Capitale-Nationale/Chaudière-Appalaches, Saguenay-Lac-St-Jean, Montréal, Mauricie et Estrie) et ont été recrutés par strates démographiques basées sur le sexe et l’âge dans le but de constituer un échantillon représentatif de la population francophone de ces régions. Les participants ont eu accès à la plateforme web de l’étude d’où ils ont rempli un ensemble de questionnaires, dont des rappels alimentaires de 24h. Les travaux de cette thèse ont premièrement permis de documenter que l’autoévaluation de la qualité de l’alimentation ne reflète pas adéquatement l’adhésion mesurée aux recommandations du GAC 2007. Nous avons également observé que la connaissance des recommandations du GAC 2007 était associée positivement à l’adhésion à celles-ci, plus particulièrement chez les individus ayant un niveau de scolarité plus faible et chez ceux vivant sans enfant. L’appréciation des aliments riches en sel et en gras a été associée négativement à l’adhésion au GAC 2007, plus particulièrement chez les hommes ainsi que chez les femmes ayant un niveau de scolarité plus faible. L’appréciation des aliments riches en sucre, quant à elle, n’était pas associée significativement à l’adhésion aux recommandations du GAC 2007. Le soutien des proches à domicile pour manger sainement a été associé à l’adhésion au GAC 2007, alors que la perception de l’environnement alimentaire physique n’y était pas associée. La motivation autodéterminée à l’égard de l’alimentation a été positivement associée à l’adhésion au GAC 2007 et la motivation non-autodéterminée y était négativement associée. Finalement, nous avons observé que la motivation autodéterminée explique en partie l’association entre certaines variables (c.-à-d., le sexe, l’éducation, le tabagisme, les connaissances en nutrition et le soutien social) et l’adhésion au GAC 2007.En somme, les travaux présentés dans cette thèse sont le résultat de la première étude visant spécifiquement l’analyse de déterminants de l’adhésion aux recommandations canadiennes en matière de saine alimentation chez les adultes québécois. Ils ont permis d’identifier des déterminants importants, tels que les connaissances en nutrition, le soutien des proches à domicile et la motivation autodéterminée qui pourront dorénavant être des cibles de choix dans le but de guider les Québécois vers des choix alimentaires plus sains.The evidence about the role of healthy eating in the prevention of chronic disease is une quivocal. However, Quebecers are struggling to meet national guidelines for healthy eating. Many factors related to the individual, the social environment and the physical food environment can influence food choices. To date, determinants of healthy eating have been scarcely studied in Canada. In addition, studies on determinants of healthy eating have often used non-validated questionnaires. The first general objective of this thesis was to develop and validate questionnaires specifically designed for French-speaking adults from the Province of Québec. Questionnaires on food liking, social support for healthy eating and the perception of the food environment were developed. As part of a validation study, 75 women and75 men were recruited and completed the questionnaires twice on a web platform. The newly developed questionnaires have demonstrated their validity and reliability through a multistage validation process. The second general objective was to identify individual, social, and environmental determinants of the adherence2007 Canada's Food Guide (CFG), in adults from the Province of Québec, and to investigate possible interactions between determinants. The 2007 CFG constituted the guidelines in force when the study was initiated. This objective was achieved in the context of the PREDISE study, for which a sample of 1,200 French speaking adults from the Province of Quebec aged 18 to 65 was recruited. Recruitment was performed in five different regions of the province (i.e., Capitale-Nationale/Chaudière-Appalaches, Saguenay-Lac-St-Jean,Montreal, Mauricie, and Estrie) and was designed so that participants represent the French-speaking adult population of each region based on sex and age. Participants completed a series of questionnaires on an internet platform, including 24-hour food recalls In this thesis, we observed that self-rated diet quality has a poor ability to predict adherence to healthy eating guidelines. It was also found that nutrition knowledge is positively associated with adherence to 2007 CFG, andthat the association is stronger among participants with a lower education level. We also observed that liking forsweet foods is not associated with diet quality, but that a stronger liking for foods high is salt and fat is associated with a lower poorer adherence to 2007 CFG, especially among men and among women with a lower education level. Moreover, our results suggest that the social environment, more precisely social support from close othersat home, may have a stronger influence on healthy eating than perceived physical environmental factors. Finally,self-determined motivation was positively associated with diet quality whereas non-self-determined motivation was negatively associated with diet quality. Self-determined motivation partly accounted for the associations ofvarious factors (i.e., sex, education, smoking status, nutrition knowledge, and social support) with adherence to2007 CFG In conclusion, this thesis is the result of the first study specifically aimed at analyzing the determinants of adherence to Canadian healthy eating guidelines in the adult population of the Province of Quebec. We have identified important determinants, such as nutrition knowledge, social support for healthy eating and selfdetermined motivation, which can henceforth be targeted in interventions and healthy eating campaigns to guide Quebecers towards healthier food choice

Development and validation of the perceived food environment questionnaire in a french-canadian population

Objective: The present study aimed to develop and validate a questionnaire assessing perceived food environment in a French-Canadian population. Design: A questionnaire, the Perceived Food Environment Questionnaire, was developed assessing perceived accessibility to healthy (nine items) and unhealthy foods (three items). A pre-test sample was recruited for a pilot testing of the questionnaire. For the validation study, another sample was recruited and completed the questionnaire twice. Exploratory factor analysis was performed on the items to assess the number of factors (subscales). Cronbach’s a was used to measure internal consistency reliability. Test–retest reliability was assessed with Pearson correlations. Setting: Online survey. Results: Men and women from the Québec City area (n 31 in the pre-test sample; n 150 in the validation study sample). The pilot testing did not lead to any change in the questionnaire. The exploratory factor analysis revealed a two-subscale structure. The first subscale is composed of six items assessing accessibility to healthy foods and the second includes three items related to accessibility to unhealthy foods. Three items were removed from the questionnaire due to low loading on the two subscales. The subscales demonstrated adequate internal consistency (Cronbach’s a=0·77 for healthy foods and 0·62 for unhealthy foods) and test–retest reliability (r=0·59 and 0·60, respectively; both P<0·0001). Conclusions: The Perceived Food Environment Questionnaire was developed for a French-Canadian population and demonstrated good psychometric properties. Further validation is recommended if the questionnaire is to be used in other populations

Validation of a french-canadian adaptation of the intuitive eating scale-2 for the adult population

Intuitive eating is an adaptive eating style based on the reliance on physiological cues to determine when, what, and how much to eat. The Intuitive Eating Scale-2 (IES-2) is a validated four-subscale tool measuring the degree of adherence to intuitive eating principles. The present series of studies aimed at evaluating the psychometric properties of a French-Canadian adaptation of the IES-2 for the adult population. The factor structure, the reliability (internal consistency and test-retest), the construct validity, and the discriminant validity were evaluated in 334 women and 75 men from the Province of Québec, Canada, across two studies. A confirmatory factor analysis upheld that the four-factor structure of the original IES-2 was adequate for the present sample of French-Canadians. The scale demonstrated adequate internal consistency and test-retest reliability. Construct validity evidence was obtained with the significant associations between intuitive eating and psychological and eating-related variables. Intuitive eating was negatively associated with eating disorder symptomatology and with food- and weight-preoccupation, and positively associated with body-esteem and well-being. The French-Canadian IES-2 was also able to discriminate between genders and body mass index categories. The properties of this new version of the IES-2 are demonstrative of a reliable and valid tool to assess intuitive eating in the French-Canadian adult population of the Province of Québec

Impact of nutritional labelling on 10-d energy intake, appetite perceptions and attitudes towards food

The purpose of this study was to investigate the impact of nutritional labelling on energy intake, appetite perceptions and attitudes towards food. During a 10-d period, seventy normal-weight (BMI<25 kg/m2) and seventy-one obese women (BMI= 30 kg/m2) were given three meals per d under ad libitum conditions. Participants were randomly assigned to one of three experimental labelling groups in which the only difference was the label posted on lunch meal entrée: (1) low-fat label, (2) energy label (energy content of the entrée and average daily needs) and (3) no label (control). Average energy intake was calculated by weighing all foods before v. after daily consumption. Hunger and fullness perceptions were rated on visual analogue scales immediately before and after each meal. Satiety efficiency was assessed through the calculation of the satiety quotient (SQ). The appreciation and perceived healthiness of the lunch entrées were rated on eight-point Likert scales. There was no difference in energy intake, SQ and attitudes towards food between the three labelling groups. Fasting hunger perception was higher in the low-fat label group compared with the two others groups (P =0·0037). No interactions between labelling groups and BMI categories were observed. In conclusion, although labelling does not seem to influence energy intake, a low-fat label may increase women’s fasting hunger perceptions compared with an energy label or no label

Are French Canadians able to accurately self-rate the quality of their diet? Insights from the PREDISE study

Cette étude se propose principalement de comparer l’autoévaluation de la qualité du régime alimentaire à un score de qualité nutritionnelle globale et à évaluer la prédictibilité de l’autoévaluation concernant l’adhésion aux recommandations de saine alimentation. Cette étude examine aussi la possible influence des caractéristiques individuelles sur l’association entre l’autoévaluation du régime alimentaire et le score de qualité nutritionnelle globale. Dans le cadre du projet PRédicteurs Individuels, Sociaux et Environnementaux (PREDISE), 1045 participants (51 % femmes) du Québec (Canada) ont autoévalué la qualité de leur régime alimentaire (« En général, diriez-vous que vos habitudes alimentaires sont : excellentes, très bonnes, bonnes, passables ou mauvaises? »). Les données de trois rappels alimentaires de 24 h via Internet ont permis le calcul du Healthy Eating Index (C-HEI), un indicateur de qualité nutritionnelle globale. Les participants percevaient leurs habitudes alimentaires comme étant excellentes (2,4 %), très bonnes (22,7 %), bonnes (49,5 %), passables (20,3 %) ou mauvaises (5,1 %). Le C-HEI variait significativement entre les catégories d’autoévaluation dans la direction attendue (p 68) de saine alimentation en présentant une sensibilité de 44,5 % et une spécificité de 81,5 % (statistique C = 0,63). L’association entre l’autoévaluation et le C-HEI était modifiée significativement par le sexe (p interaction = 0,0131); les femmes avaient un C-HEI plus élevé que les hommes dans les catégories « bonnes » et « passables ». L’autoévaluation du régime alimentaire permet de donner un aperçu de la qualité du régime alimentaire d’une population. Cependant, les résultats de cette étude suggèrent d’utiliser ces données avec prudence compte tenu de leur faible prédictibilité concernant l’adhésion aux recommandations de saine alimentation. Des caractéristiques individuelles sont susceptibles d’influencer l’aptitude à autoévaluer adéquatement la qualité du régime alimentaire.The main objective of this study was to compare self-rated diet quality to a more comprehensive score of diet quality and to assess the ability of self-rated diet quality to predict adherence to healthy eating guidelines. This study also aimed at evaluating the influence of individual characteristics on the association between self-rated diet quality and the overall diet quality score. As part of the PREDISE study, 1045 participants (51% women) from the Province of Québec, Canada, self-rated their diet quality (“In general, would you say that your dietary habits are: excellent, very good, good, fair, or poor?”). Three web-based 24-hour food recalls were completed, generating data for the calculation of the Canadian Healthy Eating Index (C-HEI), an overall diet quality indicator. Participants rated their diet quality as excellent (2.4%), very good (22.7%), good (49.5%), fair (20.3%) or poor (5.1%). The C-HEI significantly differed between diet ratings, in the expected direction (p<0.0001). Self-rated diet quality predicted adherence to healthy eating guidelines (i.e. C-HEI>68) with a sensitivity of 44.5% and a specificity of 81.5% (c-statistic=0.63). Sex significantly modified the association between self-rated diet quality and C-HEI (p interaction=0.0131); women had higher C-HEI than men in the “good” and “fair” ratings. Self-rated diet quality can be useful to obtain an overview of the diet quality of a population. Results of this study suggest that such data should be used with caution given its poor ability to predict adherence to healthy eating guidelines. Individual characteristics may influence one’s ability to appropriately self-evaluate diet quality

Eating-related and psychological outcomes of a Health at Every Size intervention in health and social services centers across the province of Quebec

Purpose: To report the outcomes of a Health at Every Size (HAES) intervention in a real-world setting. Design: Quasi-experimental design evaluating eating behaviors and psychological factors. Setting: The HAES intervention is offered in Health and Social Services Centers in Québec (Canada). Participants: For this study, 216 women (body mass index [BMI]: 35.76 [6.80] kg/m²) who participated to the HAES intervention were compared to 110 women (BMI: 34.56 [7.30] kg/m²) from a comparison group. Intervention: The HAES intervention is composed of 14 weekly meetings provided by health professionals. It focuses on healthy lifestyle, self-acceptance, and intuitive eating. Measures: Eating behaviors (ie, flexible restraint, rigid restraint, disinhibition, susceptibility to hunger, intuitive eating, and obsessive-compulsive eating) and psychological correlates (ie, body esteem, self-esteem, and depression) were assessed using validated questionnaires at baseline, postintervention, and 1-year follow-up. Analysis: Group, time, and interaction effects analyzed with mixed models. Results: Significant group by time interactions were found for flexible restraint (P = .0400), disinhibition (P < .0001), susceptibility to hunger (P < .0001), intuitive eating (P < .0001), obsessive–compulsive eating (P < .0001), body-esteem (P < .0001), depression (P = .0057), and self-esteem (P < .0001), where women in the HAES group showed greater improvements than women in the comparison group at short and/or long term. Conclusion: The evaluation of this HAES intervention in a real-life context showed its effectiveness in improving eating-, weight-, and psychological-related variables among women struggling with weight and body image

A health at every size intervention improves intuitive eating and diet quality in Canadian women

Background & aims: Health at Every Size® (HAES®) interventions focus on healthy lifestyle by promoting behavioral changes related to diet and physical activity while emphasizing self-acceptance and well-being through an empowerment and intuitive approach. The purpose of this study was to investigate the effects of a HAES® program on intuitive eating and diet quality in women. Methods: The HAES® intervention, offered by professionals from Health and Social Services Centers in Quebec (Canada), was composed of thirteen 3-h weekly meetings and a 6-h intensive day. For this study, 216 women (1.9% normal-weight, 21.1% overweight, 77.0% obese) who took part to the HAES program were compared to 110 women (3.9% normal-weight, 23.3% overweight, 72.8% obese) from a control group (waiting list). Intuitive eating was assessed using the Intuitive Eating Scale and diet quality was evaluated through the calculation of the Healthy Eating Index (HEI) from a validated web-based self-administrated food frequency questionnaire. Measurements were performed at baseline, post-intervention, and at one-year follow-up. Results: Women who participated in the HAES® program significantly increased their intuitive eating score compared to women in the control group at post-intervention and at follow-up (group by time interaction, p = 0.0002). A significant improvement in diet quality was also observed in the HAES® group in comparison with the control group at post-intervention (group by time interaction, p = 0.0139). The intuitive eating score and the HEI score were positively associated in the HAES® group at post-intervention (r = 0.20, p = 0.0237) and one-year follow-up (r = 0.22, p = 0.0359), but no such associations were noted in the control group (post-intervention, r = 0.04, p = 0.70; one-year follow-up, r = -0.15, p = 0.30). Conclusions: The HAES® program seems effective in improving intuitive eating and also favours improvements in diet quality. However, the association between intuitive eating and diet quality remains unclear, being positive and significant only after the HAES® intervention

Development and validation of a nutrition knowledge questionnaire for a Canadian population

Objective The present study aimed to develop and validate a nutrition knowledge questionnaire in a sample of French Canadians from the province of Quebec, taking into account dietary guidelines. Design A thirty-eight-item questionnaire was developed by the research team and evaluated for content validity by an expert panel, and then administered to respondents. Face validity and construct validity were measured in a pre-test. Exploratory factor analysis and covariance structure analysis were performed to verify the structure of the questionnaire and identify problematic items. Internal consistency and test–retest reliability were evaluated through a validation study. Setting Online survey. Subjects Six nutrition and psychology experts, fifteen registered dietitians (RD) and 180 lay people participated. Results Content validity evaluation resulted in the removal of two items and reformulation of one item. Following face validity, one item was reformulated. Construct validity was found to be adequate, with higher scores for RD v. non-RD (21·5 (sd 2·1) v. 15·7 (sd 3·0) out of 24, P<0·001). Exploratory factor analysis revealed that the questionnaire contained only one factor. Covariance structure analysis led to removal of sixteen items. Internal consistency for the overall questionnaire was adequate (Cronbach’s α=0·73). Assessment of test–retest reliability resulted in significant associations for the total knowledge score (r=0·59, P<0·001). Conclusions This nutrition knowledge questionnaire was found to be a suitable instrument which can be used to measure levels of nutrition knowledge in a Canadian population. It could also serve as a model for the development of similar instruments in other populations

Social support, but not perceived food environment, is associated with diet quality in French-speaking Canadians from the PREDISE study

The objectives were to assess whether social support for healthy eating and perceived food environment are associated with diet quality, and to investigate if sociodemographic characteristics moderate these associations. A probability sample of French-speaking adults from the Province of Québec, Canada, was recruited in the context of the PREDISE study. Participants reported their perceptions of supportive and non-supportive actions related to healthy eating from close others at home and outside of home (n = 952), and of the accessibility to healthy foods (n = 1035). The Canadian Healthy Eating Index (C-HEI) was calculated based on three Web-based 24 h food recalls. Multiple linear regression models showed that supportive (B = 1.50 (95% CI 0.46, 2.54)) and non-supportive (B = −3.06 (95% CI −4.94, −1.18)) actions related to healthy eating from close others at home were positively and negatively associated with C-HEI, respectively, whereas actions from close others outside of home were not. The negative association between non-supportive actions occurring at home and C-HEI was stronger among participants with lower (vs. higher) levels of education (p interaction = 0.03). Perceived accessibility to healthy foods was not associated with C-HEI (p > 0.05). These results suggest that the social environment may have a stronger influence on healthy eating than the perceived physical environment. This adds support for healthy eating promotion programs involving entire families, especially for more socioeconomically disadvantaged individuals, whose efforts to eat healthily may be more easily thwarted by non-supportive household