We monitor blood pressure and weight, but not the social needs we're lacking.
A large American study of postmenopausal women has confirmed what poets and philosophers have long suspected: the human heart is not merely a biological organ but a social one, shaped by the presence or absence of others. Researchers tracking nearly 58,000 women found that those experiencing both social isolation and loneliness faced a 27 percent greater risk of cardiovascular disease — a finding that arrives as modern life has made solitude both more common and more consequential. The study draws a careful distinction between isolation, which is physical, and loneliness, which is felt, suggesting that medicine may need to expand its understanding of what constitutes a vital sign.
- Heart disease kills one in five American women, and a new study suggests that loneliness and isolation are quietly fueling that toll in ways medicine has only begun to measure.
- The combination of feeling disconnected and being physically separated more than doubles the cardiovascular risk compared to either condition alone — a compounding effect that caught researchers' attention.
- One-third of adults over 45 report loneliness and one-fourth of those over 65 report social isolation, meaning the at-risk population is not a small outlier but a vast, largely unmonitored demographic.
- The pandemic has accelerated these conditions, raising urgent questions about whether enforced separation leaves lasting physiological damage — questions researchers say remain unanswered.
- The study's lead author is calling for social isolation and loneliness to be screened in routine clinical visits, treating human connection as a measurable health indicator alongside blood pressure and weight.
A study published in JAMA Network Open has found that postmenopausal women experiencing both social isolation and loneliness face a 27 percent increased risk of developing cardiovascular disease — a figure that held firm even after researchers accounted for obesity, smoking, high blood pressure, and other known risk factors. The finding draws on data from nearly 58,000 women enrolled in the Women's Health Initiative, 1,599 of whom developed heart disease over the study period.
The researchers were careful to separate two conditions that are often confused. Social isolation is physical — the absence of contact, conversation, and presence. Loneliness is emotional — a felt sense of disconnection that can afflict someone in a crowded room just as easily as someone living alone. Each condition independently raised cardiovascular risk, by 8 and 5 percent respectively, but their combination pushed risk dramatically higher.
Older women are disproportionately affected. Social networks tend to contract with age through loss, relocation, and changing circumstances, and women experience more isolation than men. One-fourth of adults over 65 report social isolation; one-third of those over 45 report loneliness. Lead researcher Natalie Golaszewski noted that the pandemic had pushed many people into these states, raising concern that temporary separation could harden into chronic risk.
Golaszewski's proposed remedy is modest but philosophically significant: add questions about social connection to routine medical care, alongside the blood pressure cuff and the thermometer. The suggestion reframes how medicine understands the body — acknowledging that the heart does not beat in isolation, and that the absence of human connection carries a cost that can be measured.
Researchers tracking nearly 58,000 postmenopausal women across the United States have found that the combination of social isolation and loneliness carries a measurable cost to the heart. Women who reported high levels of both conditions faced a 27 percent increase in their risk of developing cardiovascular disease, according to a study published in JAMA Network Open Journal. The finding arrives at a moment when millions have experienced enforced separation, making the distinction between these two conditions—and their separate harms—newly urgent.
The study separated what many people conflate. Social isolation is a physical fact: the absence of contact with others, no touching, no conversation, no presence. Loneliness is something else entirely—a subjective experience of disconnection that can strike even someone surrounded by people. A person living alone may not feel lonely. A person in a crowded room may feel profoundly alone. The researchers found that each condition independently raised cardiovascular risk, with social isolation accounting for an 8 percent increase and loneliness for a 5 percent increase. But when both were present at high levels, the risk jumped to between 13 and 27 percent compared to women with low levels of both.
The study followed 57,825 women who had participated in the Women's Health Initiative, a long-running health survey. Between 2011 and 2012, they answered questions about social isolation. Two to three years later, they completed a second questionnaire measuring loneliness and social support. Researchers then tracked these women through 2019, watching for cardiovascular disease diagnoses. Over that period, 1,599 women developed heart disease. The researchers controlled for known risk factors—obesity, smoking, physical inactivity, poor diet, high blood pressure, high cholesterol, diabetes, and depression—and the link between social connection and heart health remained strong.
Natalie Golaszewski, the study's lead author and a postdoctoral scholar at the University of California San Diego, emphasized the relevance of the findings. "We are social beings," she said, noting that the pandemic had pushed many people into states of isolation and loneliness that could calcify into chronic conditions. The question now is whether the damage comes from acute, sudden separation or from isolation accumulated over decades. That remains unknown, according to John Bellettiere, an epidemiologist at the same institution, who noted that further research is needed to understand the mechanism.
The numbers underscore why this matters. Heart disease is the leading cause of death for women in the United States, responsible for one in every five deaths. Among older adults, the problem is widespread: one-fourth of people 65 and older report social isolation, and one-third of those 45 and older report loneliness. Women experience more social isolation than men, the research suggests, making them particularly vulnerable. As social networks shrink with age—through death, relocation, or changing circumstances—older women face compounding risk.
Golaszewski has proposed a practical response: incorporate questions about social isolation and loneliness into routine medical care, the way clinicians now measure blood pressure, weight, and temperature. "We monitor our patients' vital signs," she said, "but it might also be beneficial to capture the social needs that individuals may be lacking to better understand cardiovascular risk and develop solutions." The suggestion amounts to a small shift in how medicine thinks about the body—acknowledging that the heart does not beat in isolation, that connection itself is a vital sign, and that the absence of it carries measurable physiological consequence.
Notable Quotes
Social isolation is about physically being away from people. Loneliness is a feeling, one that can be experienced even by people who are regularly in contact with others.— John Bellettiere, epidemiologist at UC San Diego
We are social beings. In this time of COVID-19, many people are experiencing social isolation and loneliness, which may spiral into chronic states.— Natalie Golaszewski, lead researcher
The Hearth Conversation Another angle on the story
Why does the distinction between isolation and loneliness matter so much here?
Because they're not the same thing, and treating them as if they are misses the actual problem. You can be isolated and content. You can be lonely in a crowded room. The study shows both harm the heart, but in slightly different ways. Understanding that means you can't just tell someone to "go be around people" and expect it to fix loneliness.
So what's actually happening in the body when someone is lonely?
That's the honest answer—we don't fully know yet. The researchers controlled for all the obvious culprits: smoking, inactivity, poor diet. The link remained. It could be stress hormones, inflammation, changes in sleep or immune function. It could be that loneliness changes how people make decisions about their health. The mechanism matters because it tells us where to intervene.
The study followed women for about seven years. Is that long enough to know if this is cause or effect?
That's the real limitation. We know that 1,599 women developed heart disease. We know the ones with high isolation and loneliness were more likely to be in that group. But we don't know if the isolation caused the disease, or if early disease symptoms caused people to withdraw. That's why Bellettiere said we need more research—to separate acute harm from accumulated harm over a lifetime.
Why focus on postmenopausal women specifically?
The Women's Health Initiative was already tracking them, so the data existed. But there's also something real there: women live longer, they're more likely to be widowed, and the research shows they experience more isolation than men. So this population faces particular risk.
If a doctor asks about loneliness in a routine visit, what changes?
Maybe nothing, maybe everything. If a patient admits to loneliness and the doctor takes it seriously—refers them to a community group, checks in regularly, validates it as a health concern—that itself might matter. Right now, loneliness is invisible in medical records. Making it visible is the first step.