"Round like a circle in a spiral, like a wheel within a wheel. Never ending or beginning on an ever-spinning reel" are lyrics from "The Windmills of Your Mind."

But they could describe the relationship between diabetes and depression.

It turns out that people living with diabetes are 48% more likely to develop depression than those without diabetes. And the higher the BMI of a person with diabetes, the greater his or her likelihood of developing multiple depressive symptoms.

Conversely, people with depression are 15% more likely to develop diabetes than those without symptoms of depression.

Those are the conclusions of an 11-year study of people ages 50 and older presented at the Annual Meeting of the European Association for the Study of Diabetes.

Diabetes may cause depression because of what’s called "diabetes distress," which is characterized by tension and sadness associated with the daily demands of diabetes management.

And there's some (not yet conclusive) evidence that diabetes causes hormonal and metabolic changes that can fuel depressive symptoms.

As for depression's link to diabetes — that may come from increasingly sedentary behavior and a "comfort" diet that fuels Type 2 diabetes. In addition, depression can activate the body's stress response, pumping up the hormone cortisol, which contributes to insulin resistance and elevated blood glucose.

In either case, it's essential to get effective treatment for both depression and diabetes. Ask your doctor for advice and a referral, and check out my YouTube video, "Eat to Live to 100 and Manage Stress."