Recently I had a great chance to participate in the 19th WPA World Congress of Psychiatry which took place in Lisbon 21-24 of August 2019. Such an international scientific event summarizes recent findings and sets a trend for future research.
The effect of lifestyle on mental health was one of the topics discussed at the conference. Focusing on nutritional impact in psychiatry I will review here some of the studies – research done in animal models or patients and literature reviews – which were presented at the Congress.
All the poster presentations can be viewed on the conference website https://2019.wcp-congress.com/.
Dietary patterns and mental health
- Sanchez-Villegas and colleagues from Spain presented research on the Mediterranean diet’s effects in patients recovered from depressive disorders. They found that adherence to Mediterranean diet supplemented with extra-virgin olive oil led to the improvement of depressive symptoms. This new study supports previous reports about positive effects of traditional dietary patterns compared to so-called “Western diet”, and this topic was nicely reviewed in the poster presentation of M. Jesus and colleagues (Portugal).
I presented a poster on a study done in a mouse model of Western diet feeding. We found that genetic deficiency of serotonin transporter exacerbates metabolic alterations and such behavioural consequences of the Western diet as depressive-like behaviour and cognitive impairment. In human, carriers of a genetic variant that reduces serotonin transporter expression are known to be more susceptible to emotionality-related disorders and prone to obesity and diabetes.
Vitamin D and Mental Health
Nutritional psychiatry was traditionally focused on the effects of vitamins and micronutrients on mental health. Several presentations at this conference were dedicated to the role of vitamin D in mental disorders.
Scientists from Egypt (T. Okasha and colleagues) showed their results on the correlation between serum level of vitamin D and two psychiatric disorders: schizophrenia and depression. They found lower serum vitamin D levels in the patients with schizophrenia or depression compared to healthy volunteers. These findings indicate a role of vitamin D in the development of psychiatric disorders.
However, the team from Denmark (J. Hansen and colleagues) did not find any effect of 3 months vitamin D supplementation on depression symptoms in patients with major depression. The contrariety of the studies on vitamin D benefits in mental health was presented on the review poster by R. Avelar and colleagues (Portugal).
Microbiome and Mental Health
There is increasing evidence that microbiota-gut-brain axis influences behaviour and mental health. N. Watanabe and colleagues (Japan) presented the results of a study on germfree and commensal microbiota-associated mice. They found increased aggression and impaired brain serotonin metabolism in germfree mice.
- Dias and colleagues (Portugal) performed a literature review on this topic exploring possible effects of microbiome and probiotics in mental disorder development. The most robust evidence was found for the association of microbiome alterations and depression/anxiety. Up to date literature is lacking replicated findings on proving positive effects of probiotics in mental disorders treatment.
Diabetes Type 2 and Mental Disorders
Risk factors for type 2 diabetes include diet and lifestyle habits. It is getting more obvious that there is an association between type 2 diabetes and the development of mental disorders.
- Mhalla and colleagues (Tunisia) reported a study done on patients with type 2 diabetes. They found a high prevalence of depression in women with type 2 diabetes. Also, depression in these patients was associated with poorer glycemic control.
Depression is an important factor influencing insomnia. H.C. Kim (Republic of Korea) found insomnia in one-third of patients with diabetes type 2.
The group from Romania (A. Ciobanu and colleagues) created a meta-analysis of the medical literature showing an association of diabetes type 2 with Alzheimer’s disease. They highlighted the role of insulin signaling in cognition and proposed glucose blood level control as a therapeutic approach in Alzheimer’s disease.
Thus, a lot of studies were recently done on the role of nutrition in psychiatric disorders development and therapy. However, there is still room for future discoveries!