Depression Hurts the Immune System

How the blues impairs the body's ability to stay healthy.

By Hara Estroff Marano, published on November 1, 2003 - last reviewed on November 20, 2015

Depression is a whole-body disorder. There's accumulating
evidence that the illness has deleterious effects on the heart, the
brain, the bones and metabolism. Now comes proof that it undermines the
immune system as people age.

Ohio State University researchers have found an exaggerated
inflammatory response to an immune challenge among 47 people feeling
stressed and suffering subclinical depression. Following a single flu
shot, their bodies overproduced the immune system component
interleukin-6, a marker of long-term inflammation.

Chronic inflammation is linked to cardiovascular disease,
osteoporosis, arthritis, diabetes and periodontal disease among

The study subjects, all caregivers to spouses with
Alzheimer's disease, had modest levels of depression—they
felt blue and had sleep problems—but did not have the full-blown

"A person's mental health really does matter,"
says psychologist Janice Kiecolt-Glaser, Ph.D., a coauthor of the study.
"The body responds differently—even to everyday
challenges—depending on whether a person is depressed or not. This
study shows there are long-term changes taking place in your immune