ANN ARBOR---Seniors who spend less than an hour a week volunteering are helping themselves as well as others, according to a new University of Michigan study.
The study, to be published in the Journal of Gerontology: Social Sciences, documents the link between moderate levels of volunteer activity and increased chances of survival.
"Quite a few people assume that older volunteers should benefit in terms of better health and well-being," says Marc A. Musick, a research fellow at the U-M Institute for Social Research (ISR) and first author of the study. "This study is one of the first to document that's true in a nationally representative sample of older Americans."
It's also among the first to establish that people live longer because they volunteer, rather than that people volunteer because they're healthier and hence more likely to live longer.
For the study, Musick and co-authors A. Regula Herzog and James S. House, both senior researchers at the ISR, analyzed data on 1,211 older adults. The researchers collected information through face-to-face interviews, following respondents over seven-and-a-half years, from 1986 to 1994.
During the first interview, respondents were asked whether they had volunteered in the past year for one or more groups and, if so, about how much time they had spent volunteering.
About 35 percent of the sample reported doing some volunteer work in the past year---a proportion similar to that found in other national studies of seniors. Those who said they had volunteered were also asked about how much time they had spent volunteering, with categories ranging from less than 20 hours a year up to 160 hours or more.
The researchers also obtained information on a wide range of variables related to longevity, including health conditions, physical activity, education, income, marital status, and social activity.
After controlling for these and other factors, the researchers found that respondents who volunteered for a total of less than 40 hours over the past year were less likely to die over the next seven-and-a-half years than those who didn't volunteer at all. Volunteering for a greater number of hours did not reduce the likelihood of death, and even tended to increase it.
"This finding is consonant with the role-strain hypothesis," says Musick. "For older adults, taking on too much volunteer activity may incur just enough detriments to offset the potential beneficial effects of volunteering."
Musick and colleagues also found that the protective effects of volunteering were strongest among older men and women who had low levels of social interaction, seldom seeing or talking to anyone other than their spouses or the person with whom they lived.
More research is needed, according to Musick, to identify with greater precision the factors responsible for creating the protective effects of volunteering. One possibility is that volunteering provides meaning and purpose in people's lives. Such qualities may in turn have protective effects on mortality and other health outcomes.
The research was funded by grants from the National Institute on Aging, National Institutes of Health, the Robert Wood Johnson Foundation, and the Michigan Exploratory Center for the Demography of Aging.
|% who did not volunteer||% who volunteered|
|65 - 69||58%||42%|
|70 - 74||63%||37%|
|£ 12 years||71%||29%|
|13 - 15 years||52%||48%|
|$10,000 - $29,999||60%||40%|
|* in 1994|