With depression being the psychiatric disorder incurring the largest societal costs in developed countries, there is a need to gather evidence on the role of nutrition in depression, to help develop recommendations and guide future psychiatric health care. The aim of this systematic review was to synthesize the link between diet quality, measured using a range of predefined indices, and depressive outcomes. Medline, Embase and PsychInfo were searched up to 31^st May 2018 for studies that examined adherence to a healthy diet in relation to depressive symptoms or clinical depression. Where possible, estimates were pooled using random effect meta-analysis with stratification by observational study design and dietary score. A total of 20 longitudinal and 21 cross-sectional studies were included. These studies utilized an array of dietary measures, including: different measures of adherence to the Mediterranean diet, the Healthy Eating Index (HEI) and Alternative HEI (AHEI), the Dietary Approaches to Stop Hypertension, and the Dietary Inflammatory Index. The most compelling evidence was found for the Mediterranean diet and incident depression, with a combined relative risk estimate of highest vs. lowest adherence category from four longitudinal studies of 0.67 (95% CI 0.55–0.82). A lower Dietary Inflammatory Index was also associated with lower depression incidence in four longitudinal studies (relative risk 0.76; 95% CI: 0.63–0.92). There were fewer longitudinal studies using other indices, but they and cross-sectional evidence also suggest an inverse association between healthy diet and depression (e.g., relative risk 0.65; 95% CI 0.50–0.84 for HEI/AHEI). To conclude, adhering to a healthy diet, in particular a traditional Mediterranean diet, or avoiding a pro-inflammatory diet appears to confer some protection against depression in observational studies. This provides a reasonable evidence base to assess the role of dietary interventions to prevent depression. This systematic review was registered in the PROSPERO International Prospective Register of Systematic Reviews under the number CRD42017080579.

Background: Studies of diet and depression have focused primarily on individual nutrients.Aims: To examine the association between dietary patterns and depression using an overall diet approach.Method: Analyses were carried on data from 3486 participants (26.2% women, mean age 55.6 years) from the Whitehall II prospective cohort, in which two dietary patterns were identified: ‘whole food’ (heavily loaded by vegetables, fruits and fish) and ‘processed food’ (heavily loaded by sweetened desserts, fried food, processed meat, refined grains and high-fat dairy products). Self-reported depression was assessed 5 years later using the Center for Epidemiologic Studies – Depression (CES–D) scale.Results: After adjusting for potential confounders, participants in the highest tertile of the whole food pattern had lower odds of CES–D depression (OR = 0.74, 95% CI 0.56–0.99) than those in the lowest tertile. In contrast, high consumption of processed food was associated with an increased odds of CES–D depression (OR = 1.58, 95% CI 1.11–2.23).Conclusions: In middle-aged participants, a processed food dietary pattern is a risk factor for CES–D depression 5 years later, whereas a whole food pattern is protective.

Objective: There is accumulating evidence that involvement in leisure activities may be related to risk of dementia; however, there is no consensus concerning the underlying mechanism of this association. Hypothesizing that leisure activities may contribute to cognitive reserve (CR), we examined the association between leisure activities and risk of incident dementia and its subtypes within a general population sample, categorizing leisure activity as stimulating, passive, physical, and social. The possibility that these associations may be driven by other proxies of CR was also examined. Methods: Analyses were carried out on 5,698 dementia-free participants aged 65 and over included in the Three-City cohort study in Dijon and Montpellier (France) in 1999–2001. Hazard ratios (HR) were calculated for incident dementia and its subtypes (mixed/vascular dementia and Alzheimer disease) in relation to category of leisure activity. Results: Stimulating leisure activities were found to be significantly associated with a reduced risk of dementia (n = 161, HR = 0.49, 95% confidence interval [CI]: 0.31; 0.79) and Alzheimer disease (n = 105, HR = 0.39, 95% CI: 0.21; 0.71) over the 4-year follow-up 1) independently of other proxies of CR, 2) after adjusting for vascular risk factors, depressive symptoms, and physical functioning, and 3) independently of other leisure activities. Furthermore, no significant association was found with other leisure activities and dementia after controlling for the potential confounders. Conclusion: Our findings support the hypothesis that cognitively stimulating leisure activities may delay the onset of dementia in community-dwelling elders.

Background: Indexes of diet quality have been shown to be associated with decreased risk of mortality in several countries. It remains unclear if the

Background: It has been suggested that dietary patterns are associated with future risk of depressive symptoms. However, there is a paucity of prospe