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Toxic people can cause a lot of stress with their behavior

Studies have shown that stress can accelerate biological aging

A new study investigated the effect of toxic people on biological aging

Having a toxic person in the social network accelerated aging by 1.5%

How bad are toxic people for physical health?

Supportive and positive social relationships with friends and family members can have many positive effects on health and mental well-being. In contrast, toxic friends or family members that are overly hostile, permanently passive-aggressive, or purposefully difficult can become huge stressors. Chronic stress has all sorts of negative effects on both mental and physical health. For example, stress research has shown that chronic stress can accelerate ageing and increase inflammation.

This implies an intriguing research question: Do toxic people not only worsen our mental health, but do they maybe also have a very real effect on biological age and accelerate the ageing process due to all the stress they cause?

A new study on toxic social ties and accelerated aging, and inflammation

A new study, just published in the prestigious scientific journal “Proceedings of the National Academy of Sciences of the United States of America” (or in short: PNAS), was focused on finding out whether toxic people accelerate biological aging (Lee and co-workers, 2026). In the study entitled “Negative social ties as emerging risk factors for accelerated aging, inflammation, and multimorbidity”, the research team led by scientist Byungkyu Lee from New York University used an advanced biological method called DNA methylation-based biological aging clocks. This method allowed them to determine the biological age of the volunteers in their study. Overall, data from more than 2300 volunteers from Indiana were analysed in the study. For each volunteer, the scientists determined their social networks and whether they had one or more “hasslers” In their social network. “Hasslers” were people who caused the person too much stress and difficulty. Moreover, saliva samples were collected from the volunteers to perform the advanced DNA methylation-based determination of their biological age. Moreover, the volunteers filled out further questionnaires on health and mental health.

Results of the study: Toxic people accelerate aging

Overall, the volunteers identified 8.1 percent of the overall number of people in their social networks as toxic “hasslers.” Overall, 28.8 percent of volunteers reported having one or more toxic people in the social network. 10 percent of volunteers had two or more toxic people in their social network. Women were more likely than men to have at least one toxic person in their social network. Moreover, people who felt like others depended on them a lot were more likely to have toxic people in their network.

The analysis showed that each toxic person led to a 1.5 percent faster ageing process. On average, the biological age of volunteers with toxic people in their social networks was 9 months higher than that of people of the same birth age without toxic friends or family members. Interestingly, toxic family members or toxic friends had stronger effects on ageing than toxic spouses. This may be the case because the positive effects of marriage, such as reduced loneliness, may buffer some of the negative effects of toxic social contacts. Last but not least, having a toxic person in the social network also affected multiple further biological parameters beyond biological ageing, such as inflammation levels.

Take-Away: Stay away from toxic people

The study clearly showed that toxic friends or family members have very real biological effects. They not only cause reduced mental well-being and frustration but also accelerate ageing and increase inflammation in the body. This suggests that for healthy ageing and general wellbeing, reducing contact with toxic people is highly important!

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Lee, B., Ciciurkaite, G., Peng, S., Mitchell, C., & Perry, B. L. (2026). Negative social ties as emerging risk factors for accelerated aging, inflammation, and multimorbidity. Proceedings of the National Academy of Sciences of the United States of America, 123(8), e2515331123. https://doi.org/10.1073/pnas.2515331123

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