Research shows it’s relationships, not genetics that lengthen your life
Strong social connections are linked to better physical and mental health, coping skills, sleep quality and much more
Marti Shoemaker and her husband, Julien, are off on one of what she likes to call their “little adventures.” They’re cruising kind of slowly on their beach cruiser-style bikes with the 20-inch wheels they chose because the bikes are lighter and “closer to the ground if we fall,” she says. They chat amiably as they wend their way down a paved trail past the occasional jogger near their Williston, Vermont, home.
“Shoe,” as his friends call him, says Marti’s a good listener and he’s an “overly good” talker. But the truth is that, even after 65 years of marriage, they happily report they haven’t run out of conversation topics or gotten sick of getting outside and doing things together. They walk pretty much daily and sometimes take overnight trips to Boston to visit their daughter and friends or simply see something new.
“Shoe is ready to go anywhere at any time I come up with wacky ideas. Let’s go here and look at the backyards of people’s gardens on view and little things like that,” says Marti, 86, of her 91-year-old mate. “He always says yes.”
This year, she lost way too many of her close friends to age, she says, so she’s adopted a motto that centers on the word “now.” Do it. Wear it. Now.
Research says the friends the Shoemakers have made, the family relationships they nurtured and other personal interactions have helped them achieve their long lives. Those who study lifespan say relationships matter more than genetics when it comes aging well and living long.
“Over the past few decades now, growing evidence shows people who are more socially connected live longer and people who are more isolated or lonely are at increased risk for early mortality,” according to BYU psychology professor Julianne Holt-Lunstad. She’s found that in her own research, too, including in a very recent 2022 study published in the Annual Review of Public Health.
What good relationships do
Holt-Lunstad isn’t talking about a few trickles of evidence. Research on how social connection impacts longevity forms an ocean of proof.
In 2010, she did a meta-analysis of 148 studies on the topic. Not long ago, other researchers considered 276 studies. “And there have been additional studies published since that review,” she said, noting the finding is solid and has been replicated repeatedly.
Though measurements and methods vary, the answer is always the same: Relationships impact how well and how long people live.
And the more kinds of relationships people have, the more resources they have to draw upon for a variety of types of needs, according to Holt-Lunstad. Partners, pals and the people in the neighborhood can all contribute to both mental and physical health.
Longitudinal evidence is especially strong that social relationships predict better physical health outcomes.
“We have evidence that social connectedness is linked to immune functioning, to susceptibility to viruses and an ability to mount an effective immune response to vaccines, as well as health-related kinds of behaviors,” said Holt-Lunstad.
Sleep is a prime example. People who have good relationships sleep better, while those who feel isolated or lonely — they are not the same thing — have poor sleep.
Researchers have controlled for lifestyle factors to show the link is both real and really derives from social connections, not something else, Holt-Lunstad said. A longevity benefit from relationships isn’t instead just an outgrowth of one’s age or weight or whether one drank or smoked or had diabetes or other health issues.
“I think that’s particularly important to know because there may be the assumption that people who are healthier are more likely to be social and people who are unhealthy might be more likely to be isolated,” she said. “This evidence is really part of a long-standing body of research that suggests humans are social beings and we needed to rely on others throughout human history for survival.” So social connections themselves count.
Of the unhappiness people felt during the pandemic and the long periods of being away from others that resulted, she said, “That level of distress is in essence our biology signaling an unmet need. If left unchecked, that can lead to poor health if experienced chronically. I think it shows how important our relationships are to our health. And that we need to prioritize relationships.”
Perhaps the most famous long-term study of the impacts of having or lacking relationships developed over time from the Harvard Study of Adult Development, which started following 268 Harvard sophomores in 1938 and continued to track them. They also studied inner-city teens recruited from poor neighborhoods.
“The surprising thing is that our relationships and how happy we are in our relationships has a powerful influence on our health,” Robert Waldinger, study director, a psychiatrist at Massachusetts General Hospital and a professor at Harvard’s medical school, told The Harvard Gazette in 2017. “Taking care of your body is important, but tending to your relationships is a form of self-care, too. That, I think, is the revelation.”
As time passed, study directors retired, passing the task to new generations of researchers, and the study added children and wives of participants. The children of the original subjects have reached late middle age.
They learned that it is close relationships, not money, intelligence or one’s genetic makeup, that creates lifetime happiness. This wasn’t just identified among the Harvard elite; findings proved true across the board for the inner-city participants, too.
In fact, relationship satisfaction at age 50 better predicted physical health better than did cholesterol levels. And those with good social support had less mental deterioration as they aged than those who lacked it.
“Good relationships don’t just protect our bodies; they protect our brains,” said Waldinger in a 2015 TED Talk that has been viewed 42 million times. “And those good relationships, they don’t have to be smooth all the time. Some of our octogenarian couples could bicker with each other day in and day out, but as long as they felt that they could really count on the other when the going got tough, those arguments didn’t take a toll on their memories.”
That doesn’t mean relationships are the only difference-maker.
In the book “Aging Well,” Dr. George E. Vaillant listed factors that predicted healthy aging for the Harvard men: physical activity, not smoking or abusing alcohol, being able to cope maturely with life’s ups and down, healthy weight and a stable marriage. The same was true for the inner-city men, with the addition of education.
“The more education the inner-city men obtained,” he wrote, “the more likely they were to stop smoking, eat sensibly, and use alcohol in moderation.”
Waldinger summarized the Harvard study findings for CBS “This Morning”:
- Social connections are really good for people. Isolation, for those who want to be with people, hurts. Loneliness can be toxic — and 1 in 5 Americans say they are lonely.
- The quality of close relationships is what matters. High-conflict marriage, for instance, is bad for health, while warm relationships are protective. The people who were most satisfied with their relationships at age 50 were the healthiest 30 years later.
- Good relationships protect brains, not just bodies. Having someone you can count on is protective in old age (and earlier, too). Challenges don’t take the same toll for those folks.
- The chronic stress of being unhappy breaks the body down over time.
Waldinger’s advice for building “good, close” relationships? “Giving people our full, undivided attention is probably the most valuable thing we have to offer, but it’s really hard to do. Our attention is always being pulled away and fragmented,” said Waldinger, who said the payoff is worth the fact it’s hard work that takes time.
Other studies outline the benefits of strong social bonds.
A 2020 study in the Journals of Gerontology found socially integrated women had a 10% longer lifespan and 41% higher odds of surviving to age 85 than did those who were socially isolated. That was true even after the researchers adjusted for health behaviors and depression.
A 2015 study in Clinical Psychological Science by Waldinger and others found that elderly heterosexual couples who were securely attached to each other were likely to be more satisfied in their marriages, have less depression and less unhappiness. For women, greater attachment security predicted better memory 2.5 years later.
What about genetics?
If you always assumed that how long your parents lived would provide a clue to your own longevity, you’re not alone. So it’s not surprising that a 2010 study by Ancestry.com and Calico Life Services in the journal Genetics that involved millions of people caused a genuine stir. It quantified the role of the genes one inherited on one’s lifespan at 7%, not the 20%-30% of previous estimates.
The researchers analyzed 54 million public family trees that included 400 million people on Ancestry.com.
They said assortive mating — choosing a mate based on clearly seen characteristics like having the same religious beliefs, or shared ethnicity or a similar profession — counts for more of the link to longevity that genes do.
In its report on the study, Statnews quoted Catherine Ball, Ancestry’s chief scientific officer and the study’s senior author, who said, “You’re more likely to have a lifespan similar to that of your in-laws than to an equally unrelated stranger.” She added that because people choose spouses who are like themselves in some way, they give their children something akin to a “double dose” of factors that can impact longevity but have nothing to do with genetics.
It’s rare “for a teetotaler to marry a party girl or an ultra-marathoner to marry a couch potato,” she said.
The Shoemakers are surprised for a moment to hear that genetics might not be as significant as they thought to their longevity. Then Shoe notes that maybe it’s not so surprising, really. His dad was in his early 60s when he died; her mom not quite 60.
But not all aging is the same, and genetics may be more important to super-longevity, according to a 2012 study in the journal Frontiers in Genetics. It reiterated previous studies’ findings of a “strong familial component to extreme longevity” among those who live 100 years or more.
The New England Centenarian Study at the Boston University School of Public Health published research in PLoS One that said centenarians typically have just as many genetic variants linked to increased risk for a host of age-related ills — Alzheimer’s, heart disease, stroke, diabetes and cancer, among others — as those who do not live that long. Researchers believe the centenarians’ “tremendous survival advantage” could spring from genetic variants that somehow cancel out or at least protect somewhat against the negative effects of those disease-associated genes.
But whatever longevity advantage their genes might provide doesn’t necessarily offer the well-being and happiness provided by relationships. They, too, need good relationships.
As for the Shoemakers, they’ve built strong connections to other people and to the communities where they lived ever since they married in 1957. They raised their three children in Boston and their connections there remain strong.
Though Marti says she never was much of a “joiner,” she sang with a chorale into her late 70s, happily traveling and socializing with the group. And Shoe was always happy to go along. “The camaraderie of the group was a great thing,” she says.
When they got to Vermont, they led a Compassionate Friends bereavement support group for a decade. One of their sons died when he was 20, but they never leave him out of their story, Marti says. Their relationship with him helped shape them, too.
They have loved very well. And they have the years to prove it.