Low levels of omega-3 associated with higher risk of psychosis.

New research has found that adolescents with higher levels of an omega-3 fatty acid in their blood were less likely to develop psychotic disorder in early adulthood, suggesting that it may have a potential preventative effect of reducing the risk of psychosis.

The study, led by researchers from RCSI University of Medicine and Health Sciences, is published in Translational Psychiatry.

Over 3,800 individuals in Bristol’s Children of the 90s health study were assessed for psychotic disorder, depressive disorder and generalized anxiety disorder at age 17 and at age 24.

During these assessments, blood samples were collected, and the researchers measured the levels of omega-6 fatty acids, which generally increase inflammation in the body, and omega-3 fatty acids, which generally reduce inflammation. New research has found that adolescents with higher levels of an omega-3 fatty acid in their blood were less likely to develop psychotic disorder in early adulthood, suggesting that it may have a potential preventative effect of reducing the risk of psychosis. Credit: RCSI University of Medicine and Health Sciences

While there was little evidence that fatty acids were associated with mental disorders at age 17, the researchers found that 24 year olds with psychotic disorder, depressive disorder and generalized anxiety disorder had higher levels of omega-6 than omega-3 fatty acids compared to those without these disorders.

The researchers also found that 24 year olds with psychotic disorder had lower levels of DHA, an omega-3 fatty acid typically found in oily fish or dietary supplements, than 24 year olds without psychotic disorder. In a group of over 2,700 individuals who were tracked over time, adolescents with higher levels of DHA at age 17 were 56% less likely to develop psychotic disorder seven years later at age 24. This suggests that DHA in adolescence may have a potential preventative effect of reducing the risk of psychosis in early adulthood.

These results remained consistent when accounting for other factors such as sex, body mass index, tobacco smoking, and socio-economic status.

“The study needs to be replicated, but if the findings are consistent, these results would suggest that enhanced dietary intake of omega-3 fatty acids among adolescents, such as through oily fish like mackerel, could prevent some people from developing psychosis in their early twenties,” said Professor David Cotter, senior author of the study and professor molecular psychiatry at RCSI.

“The results could also raise questions about the relationship between the development of mental health disorders and omega-6 fatty acids, which are typically found in vegetable oils.”

David Mongan, RCSI PhD student and Irish Clinical Academic Training (ICAT) Fellow, analyzed the data with the supervision of Professor David Cotter and Professor Mary Cannon from the RCSI Department of Psychiatry. The ICAT program is supported by the Wellcome Trust and the Health Research Board, the Health Service Executive National Doctors Training and Planning and the Health and Social Care, Research and Development Division, Northern Ireland.

“We need to do more research to learn about the mechanisms behind this effect, but it could possibly be related to reducing inflammation or decreasing inappropriate pruning of brain connections during adolescence,” said Dr. David Mongan, the study’s first author, who is a psychiatry trainee and PhD student at RCSI.

Reference: “Plasma polyunsaturated fatty acids and mental disorders in adolescence and early adulthood: cross-sectional and longitudinal associations in a general population cohort” by David Mongan, Colm Healy, Hannah J. Jones, Stan Zammit, Mary Cannon and David R. Cotter, 31 May 2021,Translational Psychiatry.
DOI: 10.1038/s41398-021-01425-4

This research was supported in part by a research grant from Science Foundation Ireland (SFI) and co-funded under the European Regional Development Fund. The UK Medical Research Council, Wellcome Trust and the University of Bristol provided core support for Children of the 90s, also known as the Avon Longitudinal Study of Parents and Children (ALSPAC). The data collection used in this research was joint-funded by the Medical Research Council and Wellcome Trust.

About RCSI University of Medicine and Health Sciences

RCSI University of Medicine and Health Sciences is a world-leading university for Good Health and Well-being. Ranked second in the world for its contribution to UN Sustainable Development Goal 3 in the Times Higher Education Impact Rankings 2021, it is exclusively focused on education and research to drive improvements in human health worldwide.

RCSI is an international not-for-profit university, headquartered in Dublin. It is among the top 250 universities worldwide in the World University Rankings (2021) and its research is ranked first in Ireland for citations. RCSI has been awarded Athena Swan Bronze accreditation for positive gender practice in higher education.

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About Children of the 90s

Based at the University of Bristol, Children of the 90s, also known as the Avon Longitudinal Study of Parents and Children (ALSPAC), is a long-term health-research project that enrolled more than 14,000 pregnant women in 1991 and 1992. It has been following the health and development of the parents and their children in detail ever since and is currently recruiting the children and the siblings of the original children into the study. It receives core funding from the Medical Research Council, the Wellcome Trust and the University of Bristol.

(Editor Edmond)