Nutritional Psychiatry: Where to Next?

Abstract

The nascent field of ‘Nutritional Psychiatry’ offers much promise for addressing the large disease burden associated with mental disorders. A consistent evidence base from the observational literature confirms that the quality of individuals' diets is related to their risk for common mental disorders, such as depression. This is the case across countries and age groups. Moreover, new intervention studies implementing dietary changes suggest promise for the prevention and treatment of depression. Concurrently, data point to the utility of selected nutraceuticals as adjunctive treatments for mental disorders and as monotherapies for conditions such as ADHD. Finally, new studies focused on understanding the biological pathways that mediate the observed relationships between diet, nutrition and mental health are pointing to the immune system, oxidative biology, brain plasticity and the microbiome-gut-brain axis as key targets for nutritional interventions. On the other hand, the field is currently limited by a lack of data and methodological issues such as heterogeneity, residual confounding, measurement error, and challenges in measuring and ensuring dietary adherence in intervention studies. Key challenges for the field are to now: replicate, refine and scale up promising clinical and population level dietary strategies; identify a clear set of biological pathways and targets that mediate the identified associations; conduct scientifically rigorous nutraceutical and ‘psychobiotic’ interventions that also examine predictors of treatment response; conduct observational and experimental studies in psychosis focused on dietary and related risk factors and treatments; and continue to advocate for policy change to improve the food environment at the population level.

Are Psychological Distress and Resilience Associated with Dietary Intake Among Australian University Students?

“…There is a growing body of evidence to support the link between a healthy diet and better mental health outcomes [15,49]. Much of the evidence comes from cross-sectional studies, and some studies have found no association when controlling for potential confounding factors [15].…”

“…AUDIT and DUDIT are screening tools to identify and grade alcohol and drug abuse or risk of. The cut points for the AUDIT include abstinence/low risk (0-7), moderate risk (8)(9)(10)(11)(12)(13)(14)(15), harmful/hazardous use (16)(17)(18)(19), or dependence . The cut points for the DUDIT are sex specific and include no drug related problems (males 0-5, females 0-1), drug related problems (males 6-24, females 2-24), or heavily dependent on drugs (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44).…”

“…In the general adult population, observational studies consistently demonstrate that consuming an unhealthy diet is associated with a higher likelihood of mental health problems [15]. Lower intakes of nutrient rich foods, such as fruit and vegetables, and higher intakes of energy-dense nutrient poor foods, are independently associated with higher rates of depression, and higher psychological distress and stress [15][16][17][18][19][20]. Among university students, approximately 45 studies have been conducted to date which explore associations between mental health and diet.…”

“…Most studies exploring diet and mental health are in general adult populations or older adults, and of these, some indicate that the relationship between diet and mental health is moderated by other health behaviours or socio-demographic characteristics, for example physical activity, smoking, body mass index and age [15,24,25]. Further, results from general populations may not be applicable to university students as they are a unique population group, due to elements of their environment (personal and social) that are specifically relevant to the life-stage and the setting [26].…”

Computational psychiatry 2.0 and implications for stress research

“…It remains to be tested whether these lifestyle hallmarks may be linked to western type diet. This diet is notoriously associated with high-fat and high-sugar foods consumption (55).…”