Adults 70 or older who regularly volunteer are in better physical health than those just a few years younger, according to new research from Purdue University.
The sociologists found that people ages 70-85 who regularly volunteered have younger biological profiles than those ages 58-69 who infrequently volunteer. They adjusted for a variety of factors, including whether the people in these age groups were in good enough physical health to volunteer.
"We looked at older adults engaging in a variety of productive activities, but there is something really distinctive about volunteering that positively affects a person's physical health, " said Seoyoun Kim, a doctoral student in sociology and gerontology who led the study.
The study, which is published online in The Gerontologist, measured physical health and activities such as volunteering, caregiving, community engagement and employment of independent-living people. While there has been research on the positive relationship between volunteering and self-reported physical and mental health, this study evaluates a specific biomarker that more accurately reflects people's health.
"We believe we are the first to document this link by measuring chronic inflammation," said Kenneth F. Ferraro, a Purdue distinguished professor of sociology.
Previous studies look at self-reported physician-diagnosed diseases, self-reported health, or symptoms, which can be influenced by access to health care, the researchers said.
"By using a biomarker, which is like a canary in the mine, we can clinically detect a person's physiological health, whether it has been diagnosed or not," Ferraro said.
The C-reactive protein, known as CRP, increases with aging, and higher amounts are indicative of health problems such as cardiovascular and chronic disease. This protein was measured in the National Social Life, Health and Aging Project, which is a nationally representative sample of adults who answered questions about their health and provided a blood sample. The researchers for this study analyzed data collected in 2005-06 from 1,790 people ages 57-85.
They found that CRP was about 15 percent lower for people who volunteered several times per year than for those who did not volunteer during the past year.
"Why this effect? Older adults are either losing or reducing their involvement in highly institutionalized roles, such as retirement or their children leaving the home," Kim said. "Volunteering allows them to engage in meaningful roles and stay active."
There was no positive relationship between the other activities and CRP.
"Volunteering helps many people see what is important in life and how fortunate we are," Ferraro said. "Having the feeling that you are making difference in a person's life is powerful, and our own problems may not seem so important. I also think volunteering is special because one gets to select the nature of volunteering. You are not coerced; you have some choice in it."
The researchers also analyzed if too much volunteering was an issue, but they found no negative consequences for those who volunteered the most. CRP was lowest among those who volunteered several times per week - about 25 percent lower than for those who did not volunteer. The researchers will next examine the mechanisms between volunteering and physical health, as well as cultural differences.
"In gerontology we are interested in people living well as they live longer," Kim said. "The relationship between volunteering and inflammation is telling because it's related to their quality of life and disease prevention."