People with depression live significantly shorter lives than those without it. One large study estimated that an 18-year-old with depression can expect about 47 more years of life, compared to nearly 64 more years for someone without depression. That’s a gap of roughly 16 years. The reasons go far beyond suicide: depression reshapes the body in ways that accelerate aging and fuel chronic disease.
How Many Years Depression Takes
The 16-year gap in raw life expectancy is striking enough, but it understates the full picture. When researchers also accounted for quality of life during those years, the impact was even larger. An 18-year-old with depression had about 28 quality-adjusted life years ahead of them, compared to nearly 57 for someone without depression. That’s a loss of almost 29 years of healthy, functional life, more than half of what a non-depressed person could expect.
These numbers reflect averages across populations, not a fixed destiny for any individual. Severity matters enormously. A study published in JAMA Network Open found that people with moderate to severe depressive symptoms had a 62% higher risk of dying from any cause compared to people without symptoms. Even mild depressive symptoms raised that risk by 35%.
Heart Disease Is the Biggest Threat
Most of the excess deaths in depression come not from suicide but from cardiovascular disease. People with moderate to severe depression face a 79% higher risk of dying from heart and blood vessel problems than people without depression. For ischemic heart disease specifically (the kind caused by blocked arteries), the risk is 121% higher, more than double.
Even mild depression raises cardiovascular death risk by about 49%. This isn’t just because depressed people are more likely to smoke or skip exercise, though those factors play a role. Depression itself drives physiological changes that damage the heart and blood vessels over time.
How Depression Ages the Body
Depression creates a state of chronic, low-grade inflammation throughout the body. Levels of inflammatory signaling molecules rise, promoting cell damage and accelerating the kind of wear that normally accumulates slowly with age. One measurable consequence: depression is linked to shorter telomeres, the protective caps on chromosomes that shorten each time a cell divides. Shorter telomeres are a marker of biological aging, and they’re associated with earlier onset of age-related diseases.
The body’s stress response system also becomes dysregulated. Cortisol, the primary stress hormone, tends to stay elevated in people with depression. Chronically high cortisol contributes to high blood pressure, insulin resistance, fat accumulation around the organs, and immune suppression. Over years, this creates fertile ground for heart disease, diabetes, and other conditions that shorten life.
When Depression Overlaps With Chronic Disease
Depression frequently coexists with other serious health conditions, and the combination is more dangerous than either one alone. About 34% of women and 23% of men with type 2 diabetes also have depression. When both conditions are present, the mortality risk doesn’t just add up; it multiplies. People with both depression and diabetes have roughly 2.2 times the risk of dying from circulatory disease and 2.16 times the overall mortality risk compared to people with neither condition. The combined risk exceeds what you’d expect from simply stacking the two conditions together, suggesting that depression and diabetes interact in ways that make each one worse.
The Role of Suicide
Suicide accounts for a smaller share of depression-related deaths than cardiovascular disease, but it remains a serious risk. Up to 7% of people with major depressive disorder who receive specialized psychiatric care die by suicide. Among those who survive a suicide attempt, 7% to 13% eventually die by suicide later. Globally, about 727,000 people died by suicide in 2021, making it the third leading cause of death among 15- to 29-year-olds.
There’s a notable gender split. Men are diagnosed with depression at half the rate women are, and they’re less likely to attempt suicide. Yet men die by suicide 3 to 4 times more frequently than women. This gap likely reflects both the methods men tend to use and the fact that depression in men often goes unrecognized and untreated.
Physical Inactivity Explains Part of the Gap
One of the most actionable findings in this area involves exercise. Physical inactivity accounts for roughly 25% of the increased cardiovascular death risk tied to depression in older adults. That’s a substantial chunk of a very large problem, and it’s modifiable. Depression makes movement feel impossibly hard, which is part of why this cycle is so difficult to break. But even modest increases in physical activity chip away at the excess risk in a measurable way.
Smoking, poor diet, and disrupted sleep also contribute, though researchers have found that these lifestyle factors together don’t fully explain the mortality gap. The biological mechanisms of depression itself, the inflammation, the cortisol, the accelerated cellular aging, carry independent risk even after accounting for health behaviors.
Does Treatment Close the Gap?
The relationship between antidepressant treatment and overall mortality is surprisingly murky. A large real-world study found that antidepressant use did not significantly reduce all-cause mortality after adjusting for other factors. The adjusted results hinted at a small protective effect, but the finding wasn’t statistically reliable. This doesn’t mean treatment is pointless. Antidepressants can improve functioning, reduce suffering, and lower suicide risk in the short term. But the evidence so far doesn’t show that medication alone erases the life expectancy gap.
This likely reflects the fact that most of the excess mortality comes from cardiovascular and metabolic disease, problems that require more than mood stabilization to address. Effective treatment for the whole person, including physical activity, management of chronic conditions, and sustained mental health support, probably matters more than any single intervention. The life expectancy numbers are population averages shaped by decades of undertreated or partially treated illness, not a sentence for someone actively managing their health today.