Chronic pain affects nearly 30% of people around the world, and for many, it doesn’t come alone.
Depression is a common companion, with those suffering from long-lasting pain being up to four times more likely to also experience depression.
Now, researchers from Yale University believe they’ve found a possible explanation for this connection: inflammation.
In a new study published in Science Advances, the research team found that the more places in the body a person feels chronic pain, the higher their risk of developing depression.
They also discovered that certain inflammation-related proteins in the blood, especially one called C-reactive protein, help explain this link between pain and mood.
“Pain isn’t just a physical issue,” says Dr. Dustin Scheinost, the study’s lead researcher and associate professor at Yale School of Medicine.
“It can have real mental health consequences, and inflammation may be at the heart of that connection.”
The team analyzed data from the UK Biobank, a long-term health study involving over 400,000 people in the United Kingdom.
Participants in the study reported any ongoing pain and its location—whether it was in the head, back, knees, stomach, or other areas. They also shared whether they had been diagnosed with depression.
The researchers found that both short-term (acute) and long-term (chronic) pain were linked to higher chances of depression, but chronic pain had a stronger effect. People with pain in multiple parts of the body were especially at risk.
The more widespread the pain, the more likely they were to suffer from depression.
What makes this study stand out is that it didn’t just stop at noticing the connection—it looked for possible reasons behind it.
Blood samples from participants were examined for inflammation markers like white blood cells, platelets, and most notably, C-reactive protein. This protein is made by the liver when the body is inflamed and has been linked to several health problems in the past.
They found that higher levels of C-reactive protein were strongly tied to both pain and depression. This suggests that inflammation throughout the body might play a key role in how pain leads to depression.
Dr. Rongtao Jiang, the study’s first author, says this could be a step toward better treatments. By understanding how inflammation connects physical and mental health, doctors might one day create more targeted therapies for people struggling with both chronic pain and depression.
The team plans to expand their research to include people from different backgrounds and explore other related conditions, like opioid addiction, which also often overlaps with chronic pain.
For now, this study offers a powerful reminder that the body and mind are deeply connected—and that healing one may depend on understanding the other.
If you care about inflammation, please read studies about turmeric: nature’s golden answer to inflammation, and what to eat to reduce chronic Inflammation.
For more health information, please see recent studies about how a plant-based diet could help ease inflammation ,and Vitamin D deficiency linked to increased inflammation.
Source: Yale.
