A model of the dynamics of household vegetarian and vegan rates in the U.K

Vegetarianism and mental health: Evidence from the 1970 British Cohort Study

BACKGROUND

Reducing animal product consumption has benefits for population health and the environment. The relationship between vegetarianism and mental health, however, remains poorly understood. This study explores this relationship in a nationally representative cohort in Great Britain.

METHODS

We use data from the 1970 British Cohort Study, which collected information on vegetarianism at age 30 in 2000 (n = 11,204) and psychological distress (PD) at ages 26, 30, 34, 42, and 46-48 in 2016/18. We first developed a statistical adjustment strategy by regressing PD at age 30 on vegetarianism and 14 confounders measured at ages 10 and 26. We then ran multilevel growth curve models, testing whether within-person changes in PD between ages 30 and 46-48 differed by vegetarianism, before and after statistical adjustment.

RESULTS

At age 30, 4.5 % of participants reported being vegetarian. In the cross-sectional models at age 30, vegetarians reported more distress compared with non-vegetarians in bivariate analysis (b = 0.30, 95%CI 0.09, 0.52), but this difference disappeared in the fully-adjusted model (b = 0.02, 95%CI -0.17, 0.21). In the longitudinal models between ages 30 and 46/48, there were no differences in within-person changes in psychological distress between vegetarians and non-vegetarians (p = .723). Sensitivity analyses using red meat consumption yielded similar findings.

CONCLUSION

In this British cohort, vegetarianism at age 30 was not associated with changes in psychological distress during mid-adulthood. Since psychological distress in early adulthood predicted vegetarianism at age 30, more studies are needed to disentangle the progression of this relationship over the life-course.

Meta-analysis of personality trait differences between omnivores, vegetarians, and vegans

Vegetarian and vegan diets have been increasing in the Western world. Recent research has focused on personality trait differences between dietary groups, in part because personality traits are broad characteristics that can integrate findings about different factors that motivate vegetarian or vegan diets. Previous research on personality predictors of vegetarian and vegan (veg*n) diet, however, has yielded inconsistent results. The goal of this study was to integrate the existing results of Big Five personality differences between veg*ns and omnivores as well as between vegetarians and vegans. To this end, we meta-analyzed data from 15 studies and N = 69,576 individuals from several countries. Results indicated that veg*ns were significantly higher in Openness (d = 0.40) and Agreeableness (d = 0.17) than omnivores, while vegans were significantly higher in Openness (d = 0.14) than vegetarians. This work isolates Openness and Agreeableness as important trait predictors of plant-based diets and sets the stage for future work on the factors that motivate vegetarian or vegan diet. Personality traits can provide an integrative framework for conceptualizing dietary preferences, be used to make predictions about the sources, course and correlates of dietary choices, and potentially be useful for advocates and policymakers seeking to tailor meat-reduction interventions.

Forty-five years of research on vegetarianism and veganism: A systematic and comprehensive literature review of quantitative studies

Meat production and consumption are sources of animal cruelty, responsible for several environmental problems and human health diseases, and contribute to social inequality. Vegetarianism and veganism (VEG) are two alternatives that align with calls for a transition to more ethical, sustainable, and healthier lifestyles. Following the PRISMA guidelines, we conducted a systematic literature review of 307 quantitative studies on VEG (from 1978 to 2023), collected from the Web of Science in the categories of psychology, behavioral science, social science, and consumer behavior. For a holistic view of the literature and to capture its multiple angles, we articulated our objectives by responding to the variables of "WHEN," "WHERE," "WHO," "WHAT," "WHY," "WHICH," and "HOW" (6W1H) regarding the VEG research. Our review highlighted that quantitative research on VEG has experienced exponential growth with an unbalanced geographical focus, accompanied by an increasing richness but also great complexity in the understating of the VEG phenomenon. The systematic literature review found different approaches from which the authors studied VEG while identifying methodological limitations. Additionally, our research provided a systematic view of factors studied on VEG and the variables associated with VEG-related behavior change. Accordingly, this study contributes to the literature in the field of VEG by mapping the most recent trends and gaps in research, clarifying existing findings, and suggesting directions for future research.

Self-Reported Purchasing Behaviour, Sociodemographic Predictors of Plant-Based Protein Purchasing and Knowledge about Protein in Scotland and England

Plant-based diets are seen as a food-based strategy to address both the impact of dietary patterns on the environment, to reduce climate change impact, and also to reduce rates of diet-related disease. This study investigated self-reported consumer purchasing behaviour of plant-based alternative foods (PBAF) and wholefood plant protein foods (legumes) with a cross-sectional online survey. We identified the sociodemographic factors associated with purchasing behaviour and examined knowledge about protein and plant-based diets. We recruited and obtained consent from n = 1177 adults aged >18 from England and Scotland (mean age (± standard deviation (SD)) 44 (16.4) years), across different areas of social deprivation, based on postcode. Descriptive statistics were conducted, and sociodemographic factors were examined by computing covariate-adjusted models with binary logistic regression analysis. A total of 47.4% (n = 561) consumers purchased PBAF and 88.2% (n = 1038) wholefood plant-proteins. The most frequently purchased PBAF were plant-based burgers, sausages, and mince/meatballs. Individuals from low deprivation areas were significantly more likely than individuals from high deprivation areas to purchase wholefood plant-proteins (odds ratio (OR) 3.46, p = 0.001). People from low deprivation areas were also more likely to recognise lentils as good source of protein (OR 1.94, p = 0.003) and more likely to recognise plant-based diets as healthy (OR 1.79, p = 0.004) than those from high deprived areas. These results support current trends of increasing popularity of PBAF, which is positive for the environment, but also highlights these products as being ultra-processed, which may negatively impact on health. The study also re-enforces the link between deprivation, reduced purchasing of wholefood plant-proteins and knowledge of plant-based protein and diets. Further research is needed to examine healthfulness of PBAF and how sociodemographic factors, especially deprivation, affect both food choice and consumption of wholefood plant-proteins.