Helping others isn’t only the right thing to do, it’s the healthy thing to do.

In a recent study published in the September issue of the American Journal of Public Health (AJPH), researchers found that helping others was a predictor of reduced mortality because it buffers the relationship between stress and death. In other words, stress did not predict mortality among people who had helped others in the past year, but it did predict mortality among those who had not helped others.

In fact, study researchers found that their data, along with previous data, “indicate that help given to others is a better predictor of health and well-being than are indicators of social engagement or received social support.” For the study’s purposes, researchers defined helping others as providing assistance with transportation, errands, shopping, housework, child care and other tasks.

“While we know that having social ties is beneficial for health, it’s not yet clear exactly why this is the case,” study co-author Michael Poulin, an assistant professor in the Department of Psychology at the University of Buffalo, told me via email. “One idea is that other people provide tangible and intangible help and support to us that keeps us healthy. However, the evidence for that is mixed. So another possibility is that providing help to others has health benefits. And that’s what we’re finding.”

The AJPH study notes that while social isolation is tied to an increased risk of mortality and morbidity — indeed, the relationship risk increase is comparable to that from high blood pressure, smoking and sedentary lifestyle habits — it’s somewhat unclear as to what exactly in the social environment affects health outcomes. One hypothesis has been that the help we receive from others may buffer against the physical manifestations of stress. However, that theory isn’t supported with consistent data, Poulin and his colleagues wrote. So, what about the flip side of that social equation — the health benefits of providing help instead of receiving it.

To flush out their hypothesis on the relationship between helping others and creating a buffer between stress and mortality, the researchers examined data from the Changing Lives of Older Couples study, a multi-wave study of spousal bereavement. Poulin and fellow researchers studied a five-year survival data set on nearly 850 older adults. While previous studies had shown that helping others has health benefits, the recent AJPH study found that such benefits “derive specifically from stress-buffering processes.” Authors Poulin, Stephanie Brown, Amanda Dillard and Dylan Smith write:

Experiencing stressful events significantly predicted increased mortality over the study period among those who had not tangibly helped others in the past year, but among those who had provided help, there was no association between stress and mortality. In effect, this finding suggests that, among individuals who do not help others, exposure to a stressful life event is associated with 30 percent increased mortality risk. Given that previous studies of stress and health have not differentiated those who engage in helping behavior, it is possible that the magnitude of the link between stress and health may have been underestimated in previous work. Future research should explore this possibility.

Poulin told me that one practical application of the study findings is that “we could all be more aware of the needs of those around use.”

“Providing help or care for others begins with noticing what those needs are,” he said. “But there’s good evidence that humans are adept at ignoring or glossing of others’ needs, possibly as an evolutionary adaptation to prevent ourselves from spending our resources on others. But in modern life when resources are abundant, I’d argue we have the luxury of attending to others’ needs more than our minds tend to do so by default. And doing so, ironically, may be in our own interests in the long run.”

To access a full copy of the study, visit www.ajph.org.

Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.