Recent research published in PNAS suggest that having difficult people in your close social circle is associated with a measurable increase in biological aging. Scientists have found that people who report having “nuisances” in their lives tend to have faster cellular aging and an increased risk of a variety of health problems. These findings provide evidence that promoting healthy aging requires not only strengthening supportive relationships but also reducing chronic interpersonal stress.
“This study was motivated by a simple observation: most of what we know about social relationships and health focuses on the protective power of friends and family to relieve stress and promote well-being. “We wanted to know whether that kind of chronic interpersonal stress leaves a biological imprint,” said study author Byung-gyu Lee, an assistant professor of sociology at New York University.
To answer this question, scientists analyzed data from interpersonal health interviews. This project included a representative sample of 2,345 adults living in Indiana. Participants completed a detailed survey about their social networks to identify the people they interact with regularly.
During the interviews, participants specifically named people who frequently caused them problems or made their lives difficult. Researchers defined these difficult people as “difficult people.” They also asked participants about the nature of these relationships, such as whether the difficult person was a family member, spouse, or friend.
To measure biological aging, researchers collected saliva samples from participants. They analyzed the saliva using a sophisticated experimental tool known as an epigenetic clock. These tools focus on DNA methylation. DNA methylation is a natural chemical process that turns genes on and off without changing the underlying genetic code.
By tracking these chemical tags, scientists can estimate a person’s biological age. This reflects how their cells function, not their chronological age. The researchers used two specific tools to calculate both the accumulated cellular damage and the current rate of physical decline. These biological markers were then compared to the number of stressed people reported by each participant.
The scientists found that negative social connections were relatively common, with nearly 30 percent of participants reporting at least one harasser. The data show that contact with these difficult people is not random. Women, people who smoked daily, people in poor health, and people who experienced childhood trauma were all more likely to report having stressful people in their networks.
“It was striking that negative associations were associated not only with self-reported stress and mental health, but also with molecular measures of aging,” Lee told SciPost. “Each time a person’s close network had more nuisances, it was associated with the body aging faster than biologically necessary and at a faster pace.”
“It takes about 9 extra months on the odometer and 1.5% faster on the speedometer. The impact of each nuisance may seem small, but biological aging is cumulative, so even small differences in pace can add up over years. To put this in perspective, the nuisance association is roughly 13% to 17% of the estimated impact of smoking on these same aging indicators. This is not easy.
The researchers also found evidence that relationship type matters. Family members acting as nuisances showed the strongest association with accelerated aging. “This suggests that the ‘stickiness’ or inescapability of certain roles may be particularly important,” Lee said.
In other words, family bonds are often embedded in obligations and shared spaces, making it difficult to break free from them. This inescapability can lead individuals to repeat stressful interactions. In contrast, spouses who caused difficulties did not show a similarly strong association with accelerated aging. This is probably because marriage mixes negative interactions with positive support.
Beyond biological aging, scientists have found that negative social connections are associated with a wide range of other health issues. Participants who were more bothered tended to have higher levels of systemic inflammation. They also had higher rates of depression, higher anxiety severity, and higher body mass index.
These results suggest that chronic social stress places a significant burden on the body’s physiological systems. Repeated interpersonal tensions can activate stress response systems, release hormones, and ultimately cause wear and tear on organs and tissues. This chronic activation provides a clear pathway linking bad relationships to poor physical and mental health.
“These findings suggest that promoting healthy aging requires not only strengthening supportive bonds, but also reducing chronic interpersonal stress in intimate relationships,” Lee explained.
Although this study provides robust data, there are potential misconceptions that should be avoided. Because this study is observational, it cannot prove that nuisances directly cause accelerated aging. There are other explanations, including that biologically aging people may become more irritable, leading to negative interactions.
“An important caveat is that this study is observational, so from these data alone we cannot claim that nuisance causes accelerated aging,” Lee told SciPost. “While these associations are consistent with nuisances acting as chronic stressors that cause biological wear and tear, other explanations also exist, including reverse causation (people who age faster may cause more negative interactions), perceptual biases (people with more negative emotions may perceive benign interactions as nuisances), and confounding by observed and unobserved factors.”
“To address these concerns, we took multiple steps: using linked electronic health records to adjust for prior comorbidities, investigating whether nuisance offenders predicted health at follow-up after controlling for baseline health, and occupational We included psychological and psychosocial covariates, controlled for respondents’ emotional orientation toward others, and conducted sensitivity analyzes for unobserved confounding. Although these checks increase confidence in robustness, they do not constitute causal inferences.
In future research, the scientists plan to conduct longitudinal studies to track how changes in difficult relationships predict changes in aging over time. Tracking the same person over many years can help reveal the exact direction of influence. They also hope to map specific genetic markers that change with chronic interpersonal tension.
“We hope to dig deeper into the mechanisms by conducting an epigenome-wide association study (EWAS) of ‘hustler’ exposure to identify specific DNA methylation patterns associated with chronic interpersonal strain,” Lee said.
“One of the broader messages is that ‘social health’ is not just about having people around you. It’s also about whether those close relationships are a source of support or a source of chronic tension. “While public conversations often focus on individual behaviors such as diet and exercise, our findings highlight that social environments, especially difficult relationships that people cannot easily escape, may also be part of the aging equation.”
The study, “Negative Social Connections as Emerging Risk Factors for Accelerated Aging, Inflammation, and Multimorbidity,” was authored by Byungky Lee, Gabriele Ciciurkaite, Siyun Peng, Colter Mitchell, and Brea L. Perry.
