A new study shows that seniors who volunteer are physically and mentally better off. So why doesn’t it have the same effect for people under the age of 40?

Among former President Jimmy Carter’s accolades is his devotion to volunteering.

He and his wife, Rosalynn, have been an inspiration to both young and old for their volunteer work with Habitat for Humanity.

The 39th president and the former first lady are famous for picking up a hammer to lend a hand in the construction of affordable homes for people from low-income households.

As of September 2012, Carter has been alive longer since leaving the White House than any other occupant of the Oval Office. Even with a cancer scare in 2015, he’s continued to volunteer into his 90s.

Volunteering may help benefit Carter, and others his age, not just by keeping physically fit but also by keeping mentally sharp.

“Volunteering might provide those groups with greater opportunities for beneficial activities and social contacts, which in turn may have protective effects on health status,” say the authors of a study released today. “With the aging of the population, it is imperative to develop effective health promotion for this last third of life, so that those living longer are healthier.”

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Emerging research shows that older adults who give themselves mental challenges can stave off mental health conditions like depression and even dementia.

From challenging mind games like crossword puzzles to social interaction, these benefits have been well-documented for people over the age of 40.

Volunteering one’s time is among those beneficial activities as it increases both mental and physical health.

However, new research published in the BMJ Open shows those benefits are unique only to middle-aged adults and seniors, while those under the age of 40 don’t reap the same benefits.

Researchers with the University of Southampton and the University of Birmingham, in the United Kingdom, used data from the British Household Panel Survey, which ran from 1991 to 2008 before the data was included in a larger survey.

Looking at a variety of answers to survey questions, they homed in on how often people were involved in formal volunteering. More than 66,000 responses were gathered from every other year from 1996 to 2008. About 20 percent of respondents said they’d been involved in some type of volunteer work.

Overall, women tended to volunteer more, with a quarter of those aged 60 to 74 years old reporting they volunteered at least once.

Using a 12-question general health questionnaire (GHQ-12), researchers compared the scores of those who volunteered versus those who did not. They found the scores in terms of overall mental health were slightly higher in all age groups if those individuals gave up some of their time for others.

The best scores went to those who volunteered the most, while the lowest scores were from those who never volunteered.

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While all who volunteered scored better on the GHQ-12, the scores were even better for those over the age of 40 who volunteered.

The volunteer work, researchers noted, was formally through an organization and didn’t include things like helping neighbors or volunteering at a child’s or grandchild’s school.

Those who didn’t volunteer had much lower levels of emotional well-being, which started at middle age and continued into their later years. This was independent of other factors, such as being married or single, education level, or overall health.

Researchers warn their study is observational, meaning no cause and effect should be drawn. They did, however, hypothesize why these effects could be present.

Younger people may view volunteering as another commitment or part of underlying social roles, such as work or other community activities. Middle age can be an especially hectic time with careers, raising children, or obtaining postgraduate degrees.

Older adults, especially those who’ve retired and whose children are grown, often have more free time. Volunteering can fulfill many aspects of life they might miss.

In addition, as a person ages, they may have fewer resources available and a shrinking social network. Volunteering allows them new avenues to make acquaintances and contacts outside of their immediate family and social circles.

Those who volunteer also have the advantage of using the knowledge they’ve collected over their lifetimes, offering mentoring opportunities, newfound prestige, and “knock-on effects” helpful to physical and mental health.

With the knowledge of how potentially helpful volunteering can be to an aging population, the researchers call for greater efforts to involve middle-aged and senior members of a community into volunteer roles.

“Volunteering may also provide a sense of purpose, particularly for those people who have lost their earnings, because regular volunteering helps maintain social networks, which are especially important for older people who are often socially isolated,” the study concludes.

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