Inflammation May Affect Mood and Mental Health
Inflammation is an immune response that helps the body fight germs and repair damaged tissue. However, ongoing low-level inflammation can occur with ageing, obesity and some illnesses. Researchers are now studying how this process may affect the brain and mental health.
How Inflammation May Affect Mood
Cytokines are signaling molecules that help immune cells communicate. Over 100 types exist in the body, and some can influence brain activity and how people feel.
For example, cytokines can contribute to symptoms linked with fever, tiredness and changes in mood. Studies also suggest that immune activity may affect brain regions involved in emotions.
Research involving people with rheumatoid arthritis provides further clues. Some anti-inflammatory medicines that block cytokines have also improved mood in patients. Brain scans suggest these changes may be linked to altered brain activity after cytokine blocking.
What Research Shows
A study of nearly 5,000 children found a connection between inflammation and later depression. Children with higher-than-average IL-6 levels at age nine, without depression then, were more likely to develop depression by age 18.
Another study found a relationship between immune-related diseases and earlier psychiatric diagnoses. These included conditions such as depression and anxiety.
Together, these findings suggest that the immune system and mental health may influence each other. Still, scientists say more research is needed to understand this relationship.
Why More Evidence Is Needed
Researchers do not yet know whether inflammation directly causes mental health conditions. They also cannot identify which patients might benefit from treatments targeting the immune system.
This distinction matters because inflammation is complex and serves useful functions in the body. Therefore, changing immune activity without clear evidence could carry risks.
For now, scientists view immune and mental health research as promising. Better studies may eventually help identify new approaches for depression, anxiety and other conditions.
