"It's about What You've Assigned to the Salad": Focus Group Discussions on the Relationship between Food and Mood

Omnivore, vegan and vegetarian diet quality associations with depressive symptoms: A comparative cross-sectional analysis of the Australian Longitudinal Study on Women's Health

BACKGROUND

Depressive symptoms are experienced by >350 million people globally. Research suggests that a diet rich in plant foods could be protective against depressive symptoms, but vegans and vegetarians who eat a predominant plant-based diet are known to have higher depressive symptoms than omnivores.

METHODS

This study aims to explore a secondary analysis of the association between diet quality and depressive symptoms in women born between 1973 and 1978 who follow vegan, vegetarian, and omnivore diets from the Australian Longitudinal Study of Women's Health at baseline (1996) and at three time points (2000, 2003 and 2009).

RESULTS

After controlling for covarying factors, there was a significant association between diet quality and depressive symptoms in both the plant-based and omnivore groups at both time points F(9, 4851) = 106.90, p < .001. There was no significant difference between diet quality and depressive symptoms between diet type.

CONCLUSIONS

Despite diet type (plant-based or omnivore), adhering to a high-quality diet may decrease depressive symptoms and a low-quality diet may increase depressive symptoms in Australian women.

LIMITATIONS

Caution should be exercised when interpreting these results due to the small sample sizes and small resulting coefficients, there is uncertainty that coefficients this small can be associated with any meaningful change in an individual being treated for depressive symptoms in a clinical setting.

Cohort profile: rationale and design of the Resource Center for Health Science (RECHS) project - a study of health hazards and medical cost burden among the Japanese population

PURPOSE

The increased global burden of non-communicable diseases and mental disorders is an urgent health challenge for countries around the entire world, especially those experiencing super-ageing societies, where over 21% of the population is age 65 years or older. Japan is the world's most rapidly ageing society, and as a result, medical costs are also rising dramatically. With the aims of establishing a foundational framework for future research efforts, primarily focusing on the development of a personal health record (PHR) system, and creating a long-term repository for bioresources integrated with PHRs, this study investigated potential health risks and future healthcare burdens based on a longitudinal analysis of health records.

PARTICIPANTS

The Resource Center for Health Science (RECHS) project is a long-term, prospective biobank project, population and health check-up-based cohort that primarily investigates the associations between lifestyle and environmental factors and some surrogate markers of non-communicable diseases, such as diabetes, hypertension, cardiovascular disease and cancer. Starting in 2010, we initiated an annual cohort study among voluntary participants recruited from health check-up programmes and collected data from the following sources: a self-administered baseline questionnaire that included items on dietary habits and stress, a Brief Self-Administered Diet History Questionnaire, the Centre for Epidemiologic Studies Depression Scale and the General Health Questionnaire-28.

FINDINGS TO DATE

For this prospective cohort study, we planned to enrol approximately 10 000 participants. We collected and stored serum samples from all participants for future analyses. The study participants who still were able to participate in these health check-ups and their outcomes were then obtained from the measurements and questionnaire responses.

FUTURE PLANS

Insights emerging from the RECHS study can provide researchers and public health policy administrators with evidence to aid in the prevention of non-communicable diseases and clarify the most malleable status to implement preventive measures.

Nutritional considerations in major depressive disorder: current evidence and functional testing for clinical practice

Depression is a multifaceted condition with diverse underlying causes. Several contributing and inter-related factors such as genetic, nutritional, neurological, physiological, gut-brain-axis, metabolic and psychological stress factors play a role in the pathophysiology of depression. This review aims to highlight the role that nutritional factors play in the aetiology of depression. Secondly, we discuss the biomedical and functional pathology tests which measure these factors, and the current evidence supporting their use. Lastly, we make recommendations on how practitioners can incorporate the latest evidence-based research findings into clinical practice. This review highlights that diet and nutrition greatly affect the pathophysiology of depression. Nutrients influence gene expression, with folate and vitamin B12 playing vital roles in methylation reactions and homocysteine regulation. Nutrients are also involved in the tryptophan/kynurenine pathway and the expression of brain-derived neurotrophic factor (BDNF). Additionally, diet influences the hypothalamic-pituitary-adrenal (HPA) response and the composition and diversity of the gut microbiome, both of which have been implicated in depression. A comprehensive dietary assessment, combined with appropriate evaluation of biochemistry and blood pathology, may help uncover contributing factors to depressive symptoms. By employing such an approach, a more targeted and personalised treatment strategy can be devised, ultimately leading to improved patient outcomes.

Perspectives on Healthy Eating of Adult Populations in High-Income Countries: A Qualitative Evidence Synthesis

BACKGROUND

Understanding how individuals currently perceive healthy eating is essential for developing food policies and dietary recommendations that improve the health and well-being of populations. The purpose of this qualitative evidence synthesis was to systematically outline the views and understandings of healthy eating, focusing on how foods are classified as healthy and unhealthy and what meanings are attached to food and eating by the general adult population in high-income countries.

METHODS

A systematic search of four electronic databases was conducted and yielded 24 relevant primary qualitative studies of generally healthy, community-dwelling adults.

RESULTS

Thematic synthesis of the included studies identified three analytic themes: constructions of healthy and unhealthy eating, considerations on dietary recommendations, and meanings attached to food and eating. Study participants generally understood what constitutes a healthy and unhealthy diet which was in line with dietary recommendations, but those of lower socioeconomic status exhibited gaps in nutrition knowledge. Participants expressed diverse opinions on dietary recommendations, including skepticism and a lack of trust. Food and eating were associated with various meanings, including pleasure, stress relief, and feelings of guilt. Moral, health, and sociocultural considerations also played a role in dietary behaviors.

CONCLUSIONS

The findings suggest that improving population diet requires considering how dietary recommendations are phrased and communicated to ensure that healthy eating is associated with pleasure and immediate well-being. This review provides valuable insights for developing consumer-oriented, practicable, and acceptable food policies and dietary recommendations that effectively improve population health and well-being.

A longitudinal analysis of Australian women's fruit and vegetable consumption and depressive symptoms

BACKGROUND

In Australia, women report higher rates of depressive symptoms than men. Research suggests that dietary patterns rich in fresh fruit and vegetables could protect against depressive symptoms. The Australian Dietary Guidelines suggest that consuming two servings of fruit and five serves of vegetables per day is optimal for overall health. However, this consumption level is often difficult for those experiencing depressive symptoms to achieve.

AIMS

This study aims to compare diet quality and depressive symptoms in Australian women over time using (I) two serves of fruit and five serves of vegetables per day (FV7), and (ii) two serves of fruit and three serves of vegetables per day (FV5).

MATERIALS AND METHODS

A secondary analysis was conducted using data from the Australian Longitudinal Study on Women's Health over 12 years at three time points 2006 (n = 9145, Mean age = 30.6, SD = 1.5), 2015 (n = 7186, Mean age = 39.7, SD = 1.5), and 2018 (n = 7121, Mean age = 42.4, SD = 1.5).

RESULTS

A linear mixed effects model found, after adjusting for covarying factors, a small significant inverse association between both FV7 (b = -.54, 95% CI = -.78, -.29) and FV5 (b = -.38, 95% CI = -.50, -.26) in depressive symptoms.

DISCUSSION

These findings suggest an association between fruit and vegetable consumption and decreased depressive symptoms. The small effect sizes indicate caution should be taken in interpreting these results. The findings also suggest that current Australian Dietary Guideline recommendations need not be prescriptive to two fruit and five vegetables for impact on depressive symptoms.

CONCLUSIONS

Future research could evaluate reduced vegetable consumption (three serves per day) in identifying the protective threshold for depressive symptoms.

The Association between Vegan, Vegetarian, and Omnivore Diet Quality and Depressive Symptoms in Adults: A Cross-Sectional Study

Dietary patterns and depressive symptoms are associated in cross-sectional and prospective-designed research. However, limited research has considered depression risk related to meat-based and plant-based dietary patterns. This study explores the association between diet quality and depressive symptoms across omnivore, vegan, and vegetarian dietary patterns. A cross-sectional online survey utilised the Dietary Screening Tool (DST) and the Centre for Epidemiological Studies of Depression Scale (CESD-20) to measure diet quality and depressive symptoms, respectively. A total of 496 participants identified as either omnivores (n = 129), vegetarians (n = 151), or vegans (n = 216). ANOVA with Bonferroni post hoc corrections indicates that dietary quality was significantly different between groups F(2, 493) = 23.61, p < 0.001 for omnivores and vegetarians and omnivores and vegans. Diet quality was highest in the vegan sample, followed by vegetarian and omnivore patterns. The results show a significant, moderately negative relationship between higher diet quality and lower depressive symptoms (r = -0.385, p < 0.001) across groups. Hierarchical regression showed that diet quality accounted for 13% of the variability in depressive symptoms for the omnivore sample, 6% for vegetarians, and 8% for vegans. This study suggests that diet quality in a meat-based or plant-based diet could be a modifiable lifestyle factor with the potential to reduce the risk of depressive symptoms. The study indicates a greater protective role of a high-quality plant-based diet and lower depressive symptoms. Further intervention research is needed to understand the bi-directional relationship between diet quality and depressive symptoms across dietary patterns.

"Maybe it's Not Just the Food?" A Food and Mood Focus Group Study

Epidemiological and intervention studies in nutritional psychiatry suggest that the risk of mood disorders is associated with what we eat. However, few studies use a person-centred approach to explore the food and mood relationship. In this qualitative study of 50 Australian participants, we explored individuals' experiences with food and mood as revealed during focus group discussions. Using a thematic template analysis, we identified three themes in the food and mood relationship: (i) social context: familial and cultural influences of food and mood, (ii) social economics: time, finance, and food security, and (iii) food nostalgia: unlocking memories that impact mood. Participants suggested that nutrients, food components or food patterns may not be the only way that food impacts mood. Rather, they described the social context of who, with, and where food is eaten, and that time, finances, and access to healthy fresh foods and bittersweet memories of foods shared with loved ones all impacted their mood. Findings suggest that quantitative studies examining the links between diet and mood should look beyond nutritional factors and give increased attention to the cultural, social, economic, and identity aspects of diet.