You are probably aware that lonely people tend to suffer with poorer health. Now research is uncovering exactly how this emotional state impacts our immune system.

A large body of research has linked loneliness with higher rates of all sorts of diseases, including Alzheimer’s disease, cancer and heart disease. If a lonely person is diagnosed with a serious disease, they tend to have a poorer outcome.

The white blood cells of lonely people behave in a way that increases inflammation in the body. Inflammation is an underlying driver of conditions such as allergies, autoimmune disease and pain. The immune cells also produce lower levels of antiviral compounds called interferons. This places a person at higher risk of infections.

A recent study published in the Proceedings of the National Academy of Sciences looked at 141  people over the space of 5 years. Each year researchers measured how lonely the people felt and conducted blood tests to look at the activity of immunity and inflammation. They also measured blood levels of the hormone norepinephrine (also known as noradrenalin). This is a hormone we normally produce while stressed.

Results showed that lonely people experienced higher blood levels of norepinephrine for longer. So essentially their bodies felt stressed out all the time. The genes in stressed people reduced the body’s sensitivity to the hormone cortisol. Cortisol is normally supposed to reduce inflammation in the body, but in lonely people it doesn’t happen as effectively.

Humans are social creatures. We need contact with and support from other people. Unfortunately modern living has created an epidemic of lonely people.  It’s not just older individuals who live alone who experience loneliness. It can affect people of any age who seem to have busy, active lives. If you feel like you don’t have enough close friends for emotional support, perhaps try engaging in a new recreational activity, such as a yoga class, dance class, self defense class, book club; anything that interests you would do. Perhaps you could volunteer at a nursing home or local animal shelter. You never know who you’ll meet and how it could impact your life.