Stages of Change toward Meat Reduction: Associations with Motives and Longitudinal Dietary Data on Animal-Based and Plant-Based Food Intakes in French Adults.

BACKGROUND: Reducing meat consumption is advocated for healthier and more sustainable diets. However, behavioral studies are needed to better understand the mechanisms underlying meat-reducing dietary changes. OBJECTIVES: The main aim of this study was to compare the motives associated with stages of change toward meat reduction in French adults, using the transtheoretical model (TTM). A second aim was to investigate the associations between stages of change and adherence to dietary patterns favoring a better balance of animal and plant food consumption over time. METHODS: This longitudinal study included 25,143 non-vegetarian participants of the web-based NutriNet-Santé cohort with a mean follow-up of 6.2 (SD = 2.6) y. Dietary data were obtained from 24-h dietary records over the period 2009-2019. The contribution of meat to total energy intake and scores measuring the contribution of healthy and unhealthy plant-based foods to the diet were computed. A questionnaire completed in 2018 allowed us to identify the TTM stages of change related to meat reduction (precontemplation, contemplation, preparation, action, and maintenance), and recorded motives related to meat consumption. We used multivariate linear mixed models for repeated data to assess associations between food intake changes and stages, and logistic regression for motives, presented as adjusted frequencies. RESULTS: Participants in later stages were characterized by a significantly higher decrease in meat intake over time, compared with the earliest stage (for example, ßmaintenance ∗ time = -0.08, P < 0.0001), and a higher increase in the healthy plant-based food consumption score over time (for example, ßmaintenance∗time = 0.11, P < 0.0001). Concerns about health, nutrition, and the environment were the most frequently cited motives for reducing meat consumption at all stages. CONCLUSIONS: Individuals who had already initiated meat reduction adhered to healthier and more sustainable diets than meat continuers. Characterizing motives according to readiness to reduce meat consumption could support tailored public health campaigns. TRIAL REGISTRATION NUMBER: The study protocol is registered at clinicaltrials.gov with Clinical Trial Registry number NCT03335644 available at https://clinicaltrials.gov/ct2/show/NCT03335644.

Associations between measures of socio-economic position and sustainable dietary patterns in the NutriNet-Santé study.

OBJECTIVE: We aimed to explore the relationship between socio-economic characteristics and sustainable dietary patterns. DESIGN: Dietary data were derived from a web-based FFQ. Diet sustainability was evaluated using a modified Sustainable Diet Index, comprising nutritional, environmental and cultural components (higher scores expressing higher sustainability). The socio-economic position markers were education, household income and occupation status. Multi-adjusted linear and Poisson regression models were used to assess the cross-sectional association of the markers of socio-economic status with a sustainable diet and sustainability subcomponents, respectively. SETTING: France. PARTICIPANTS: 29 119 NutriNet-Santé participants. RESULTS: Individuals with a more sustainable diet had slightly higher diet monetary cost, lower total energy intake and consumed less animal-based foods than their counterparts. Lower education level was associated with lower overall diet sustainability (ßprimary v. postgraduate = -0·62, 95 % CI (-0·72, -0·51)) and nutrition, socio-cultural and environmental subscores. Manual workers and employees had a lower modified Sustainable Diet Index than intermediate professionals (ßmanual workers v. intermediate professionals = -0·43, 95 % CI (-0·52, -0·33) and ßemployees v. intermediate professionals = -0·56, 95 % CI (-0·64, -0·48)). Participants with the lowest v. highest incomes had a higher environmental subscore but a lower socio-cultural subscore, whereas the results were less marked for occupational status. CONCLUSIONS: Overall, our results documented associations between socio-economic status and the level of diet sustainability, arguing for the implementation of appropriate food policies to promote sustainable diets at lower cost.

Rebalancing meat and legume consumption: change-inducing food choice motives and associated individual characteristics in non-vegetarian adults.

BACKGROUND: A shift toward more plant-based foods in diets is required to improve health and to reduce environmental impact. Little is known about food choice motives and associated characteristics of those individuals who have actually reduced their consumption of animal-based foods. The aim of this cross-sectional study was to identify change-inducing motives related to meat and legume consumptions among non-vegetarians. The association between change-inducing motives and individual characteristics was also studied. METHODS: This study included 25,393 non-vegetarian participants in the French NutriNet-Santé cohort (77.4% women, mean age 55.4 ± 13.9 y.). The motives related to the declared change in meat and legume consumptions (e.g., taste, environment, social pressure) were assessed by an online questionnaire in 2018. For each motive, respondents could be classified into three groups: no motive; motive, not change-inducing; change-inducing motive. Associations between change-inducing motives and individual characteristics were evaluated using multivariable polytomic logistic regressions. Characteristics of participants who rebalanced their meat and legume consumptions were also compared to those who reduced their meat but did not increase their legume consumption. RESULTS: Motives most strongly declared as having induced a change in meat or legume consumptions were health and nutrition (respectively 90.7 and 81.0% declared these motives as change-inducing for the meat reduction), physical environment (82.0% for meat reduction only) and taste preferences (77.7% for legume increase only). Other motives related to social influences, meat avoidance and meat dislike were reported by fewer individuals, but were declared as having induced changes in food consumption. Most motives that induced a meat reduction and a legume increase were more likely to be associated with specific individual characteristics, for example being a woman or highly educated for health motives. CONCLUSIONS: Besides the motives reported as important, some motives less frequently felt important were declared as having induced changes in meat or legume consumptions. Change-inducing motives were reported by specific subpopulations. Public campaigns on health and sustainability could usefully develop new tools to reach populations less willing to change. TRIAL REGISTRATIONS: The study was registered at ClinicalTrials.gov (NCT03335644).

Higher adherence to the EAT-Lancet reference diet is associated with higher nutrient adequacy in the NutriNet-Santé cohort: a cross-sectional study.

BACKGROUND: In 2019, the EAT-Lancet Commission proposed a planetary and healthy reference diet; however, its nutritional quality has been rarely evaluated. OBJECTIVE: Across different adherence levels to the EAT-Lancet reference diet, the following were our objectives:1) describe the food and nutritional intakes of the French population, 2) evaluate the nutrient quality, and 3) investigate the consistency between the French national recommendations and the EAT-Lancet reference diet. METHODS: This cross-sectional study was conducted among participants of the NutriNet-Santé cohort, and the sample was weighted on the characteristics of the general French population. Adherence to the EAT-Lancet reference diet was estimated using the EAT-Lancet Diet Index (ELD-I). Usual nutrient intakes were obtained using the variance reduction method. We used the estimated average requirements cut-point method to estimate the proportion of participants who meet their respective nutritional requirements. Furthermore, the adequacy of the French food-based dietary recommendations [Programme National Nutrition Santé (PNNS)] according to adherence to the EAT-Lancet reference diet was studied. RESULTS: The weighted sample was composed of 98,465 participants. Except for bioavailable zinc and vitamin B12, we observed a decrease in the nutrient inadequacy prevalence when the adherence to the EAT-Lancet reference diet increased, particularly for vitamin B9 (Q1 = 37.8% compared with Q5 = 5.5%, P < 0.0001) and vitamin C (Q1 = 59.0% compared with Q5 = 10.8 %, P < 0.0001). However, inadequacy prevalence remained high in all ELD-I quintiles, particularly for fiber (95.9%), vitamin B1 (70.8%), iodine (48.4%), and magnesium (76.8%). Higher ELD-I score was associated with higher adherence for most components of the PNNS, except for food groups that are not specifically included in the EAT-Lancet reference diet and are typical of the French diet, including alcohol, processed meat, and salt. CONCLUSION: In the French context, although issues with the intake of certain nutrients may occur, a diet that remains within the planetary limits as the EAT-Lancet reference diet allows a favorable nutritional quality. This trial was registered at clinicaltrials.gov as NCT03335644.

Environmental pressures and pesticide exposure associated with an increase in the share of plant-based foods in the diet.

Diets rich in plant-based foods are encouraged for human health and to preserve resources and the environment but the nutritional quality and safety of such diets is debated. This study aimed to model nutritionally adequate diets with increasing plant food content and to characterise the derived diets using a multicriteria approach including, nutrients intake, environmental pressures and exposure to pesticides. Using data of the NutriNet-Santé cohort (N = 29,413), we implemented stepwise optimization models to identified maximum plant-food content under nutritional constraints. Environmental indicators at the production level were derived from the DIALECTE database, and exposure to pesticide residues from plant food consumption was estimated using a contamination database. Plant-based foods contributed to 64.3% (SD = 10.6%) of energy intake in observed diets and may reach up to 95% in modelled diets without jeopardizing nutritional status. Compared to the observed situation, an increase in plant-based foods in the diets led to increases in soy-based products (+ 480%), dried fruits (+ 370%), legumes (+ 317%), whole grains (+ 251%), oils (+ 144%) and vegetables (+ 93%). Animal products decreased progressively until total eviction, except for beef (- 98%). Dietary quality (estimated using the Diet Quality Index Based on the Probability of Adequate Nutrient Intake) was improved (up to 17%) as well as GHGe (up to - 65%), energy demand (up to - 48%), and land occupation (- 56%) for production. Exposures to pesticides from plant-based foods were increased by 100% conventional production and to a much lesser extent by 100% organic production. This study shows that shifting to nutritionally-adequate plant-based diets requires an in-depth rearrangement of food groups' consumption but allows a drastic reduction environmental impact. Increase exposure to pesticide residues and related risks can be mitigated by consuming foods produced with low pesticide input.

Association between Self-Reported Gluten Avoidance and Irritable Bowel Syndrome: Findings of the NutriNet-Santé Study.

Self-management of irritable bowel syndrome (IBS) is increasingly focusing on exclusion diets. In particular; patients are showing a significant interest in the gluten-free diet for the treatment of IBS. However; the lack of scientific evidence prevents the establishment of clear dietary guidelines and attention is needed as dietary restriction can lead to potentially adverse effects. This cross-sectional study aims to explore the practice of gluten avoidance in participants identified with IBS in a large cohort of non-celiac French adults. The population included 15,103 participants of the NutriNet-Santé study who completed a functional gastrointestinal disorder questionnaire based on the Rome III criteria to identify IBS in 2013 and a food avoidance questionnaire in 2016. Data on diet and anthropometric and sociodemographic characteristics were collected. Multivariate logistic regression models were used to compare the avoidance of gluten between IBS and non-IBS participants. Participants were mainly women (73.4%) and the mean age in this population was 55.8 ± 13.2 years. Among these individuals, 804 (5.4%) participants were identified as IBS cases. Among them, the prevalence of gluten avoidance was estimated at 14.8%, of which 3.0% reported total avoidance; versus 8.8% and 1.6% in non-IBS participants. After adjustments; gluten avoidance was higher in IBS participants compared to their non-IBS counterparts: (OR = 1.86; 95%CI = 1.21, 2.85) for total and (OR = 1.71; 95%CI = 1.36, 2.14) for partial avoidance. Participants identified with IBS were more associated with gluten avoidance than non-IBS participants. Further studies are needed to explore the long-term consequences of dietary interventions and to provide consistent dietary guidance connected to patient perception.