A new cross-sectional analysis from United Kingdom Biobank data confirms the well-known benefit of omega-3s for emotional well-being. Researchers found a strong association between circulating omega-3 levels and diagnosed occurrences of depression and anxiety.
Why is the link between omega-3s and mental health important?
Mental and emotional well-being are at the forefront of consumers’ minds, according to the 2025 Insights Supplement Survey from the Industry Transparency Center.
Stress, anxiety and mood are global concerns, yet there is a large gap between how many respondents reported concerns versus how many take supplements to address those concerns, presenting a key opportunity for the dietary supplement industry.
“Our findings from more than a quarter-million adults show a clear and consistent link between higher omega-3 status and lower chance of having a history of both depression and anxiety,” said William Harris, Ph.D., president of the Fatty Acid Research Institute (FARI) and lead author on the study.
“When you consider the biological roles of EPA and DHA in inflammation, neuronal function and neurotransmitter signaling, these associations make a great deal of sense,” Harris said.
Brain health is the third most important healthy aging benefit to supplement consumers, according to a Nutrition Business Journal survey.
SupplySide Supplement Journal previously reported on the link between omega-3s and a decrease in self-harm and suicide ideation, as well as the benefits afforded by omega-3s for those experiencing cognitive decline and the association with lower dementia risk.
What are the key takeaways from this omega-3 analysis?
Plasma omega-3 fatty polyunsaturated fatty acid (PUFA) levels are inversely associated with documented anxiety and/or depression, showing increased circulating omega-3 PUFA levels may reduce risk of mental illness.
What were the details of the UK Biobank omega-3 study?
Design: The data were obtained from the United Kingdom Biobank (UKBB), which is a population-based cohort of over 500,000 individuals aged 40-70 recruited between April 2007 and December 2010.
Study size: Researchers used data from over 258,000 participants who had plasma fatty acid level data available. Some analyses also used data from over 468,000 participants who reported using fish oil supplements.
Outcomes measured: Plasma omega-3 PUFA levels were measured using nuclear magnetic resonance (NMR). Researchers collected depression and/or anxiety diagnoses from ICD-10 (International Classification of Diseases) codes present in medical records when the fatty acid data were collected.
What were the results of this cross-sectional analysis?
Several fatty acid levels, including docosahexaenoic acid (DHA) and total omega-3, were significantly inversely associated with depression and/or anxiety diagnoses.
Researchers also found that fish oil supplementation significantly reduced the likelihood of mental health diagnoses. Consumption of oily fish also was inversely associated, though the correlation was less clear than with fish oil supplements.
How does this build upon prior research?
Researchers at FARI have conducted several analyses linking omega-3 levels to mental and emotional well-being, as previously reported by SupplySide Supplement Journal.
Omega-3s have been suggested as an adjunct therapy in major depressive disorder because of their ability to modulate neuroinflammation, in line with mechanisms suggested within the current study. Additionally, an international task force involving the World Federation of Societies of Biological Psychiatry reported omega-3s as one of its currently recommended nutraceuticals in the treatment of psychiatric disorders.
Various review articles largely support the findings from the most recent study, stating that while there is enough evidence demonstrating the benefits of omega-3s for depression, results are not all consistent and warrant further investigation. One meta-analysis reported eicosapentaenoic acid (EPA) improved depression systems but DHA did not have the same impact.
