A new study might have connected the dots between diabetes and depression with high levels of inflammation in patients  Researchers found that people with both diabetes and depression have higher inflammation in their blood, when compared to those with just diabetes.

The study, conducted by the Institute of Psychiatry at King’s College London examined 1,227 people with newly-diagnosed type 2 diabetes. Those who had depression were younger and heavier. They also had more circulatory and heart problems as well as more inflammation in their blood. “We asked, why is depression so bad for diabetes? The study suggests that we have a possible biological explanation. Inflammation may be driving a number of different long-term conditions. That’s quite a new way of thinking of the mind and the body,” Dr. Khalida Ismail told Reuters Health

For the study, researchers analyzed the differences between participants, such as their age, sex, amount of body fat, and use of certain medications. Several inflammatory markers were linked to depression. So what is the relationship between inflammation in depression and diabetes patients? “It’s a bit like an engine,” Ismail said. “You’re running a bit higher. So there’s this constant low-grade inflammation and that’s causing damage to your brain, your pancreas, and to your vascular system.”

Researchers say the correlation between depression and inflammation is very tricky to understand. Dr. Anne Peters told Reuters that “the development of depression could in part be triggered by inflammation, but we don’t know what comes first. This paper can’t prove causality. The interplay is so complicated.” According to the Centers For Disease Control and Prevention (CDC), people with diabetes double their chances of developing depression, while people with depression are more likely to develop diabetes. The correlation between the two still requires a lot more research.

The CDC reports that diabetes affects one in 12 people, while one out of 10 adults has depression. Both illnesses can be treated with proper nutrition and exercise. “If you exercise, you feel better, your inflammatory markers improve. It’s all about lifestyle interplaying with your health. We’re just living lives we were not made to live. We sit still too much at work. We’re caged up in a way,” Peters said. 

Both depression and diabetes can be treated simultaneously, according to Everyday Health. Some symptoms you can look for include irritability, loss of appetite or overeating, pain, cramps, and headaches.

Source: Laake J, Stahl D, Amiel S, et al. The Association Between Depressive Symptoms and Systemic Inflammation in People With Type 2 Diabetes: Findings From the South London Diabetes Study. Diabetes Care. 2014.