Death may be inevitable, but that hasn't stopped health researchers from looking for ways to postpone it as long as possible. Their new candidate is something that's free, painless, doesn't taste bad and doesn't require you to sweat: gratitude.
A new study of nearly 50,000 older women found that the stronger their feelings of gratitude, the lower their chances of dying in the next three years.
The results will be appreciated by those who naturally have an inclination to give thanks. Those who do not may be grateful to know that with practice, they may be able to enhance their feelings of gratitude and also reap the benefits of longevity.
“It's an exciting study,” said Joel Wong, a professor of counseling psychology at Indiana University who researches gratitude interventions and practices and was not involved in the new work.
There is growing evidence linking gratitude to a range of physical and mental health benefits. People who score higher on gratitude measures have been found to have better biomarkers of cardiovascular function, immune system inflammation, and cholesterol. They are more likely to take their medications, exercise regularly, have healthy sleep habits, and eat a balanced diet.
Gratitude is also associated with a lower risk of depression, better social support, and greater purpose in life, all of which are linked to longevity.
However, this is the first time researchers have directly linked gratitude to a lower risk of premature death, Wong and others said.
“It’s not surprising, but it’s always good to see empirical research supporting the idea that gratitude is not only good for mental health, but also for living a longer life,” Wong said.
Study leader Ying Chen, an empirical research scientist at Harvard University’s Human Prosperity Program, said she was struck by the dearth of studies on gratitude and mortality. So she and her colleagues turned to data from the Nurses’ Health Study, which has been tracking the health and habits of thousands of American women since 1976.
In 2016, those initiatives included a test to measure nurses’ feelings of gratitude. Women were asked to use a seven-point scale to indicate the extent to which they agreed or disagreed with six statements, including: “I have so many things to be grateful for in my life” and “If I had to list everything I’m grateful for, it would be a very long list.”
In all, 49,275 women responded to the survey, and researchers divided them into three roughly equal groups based on their gratitude scores. Compared with women with the lowest scores, those with the highest scores tended to be younger, more likely to have a spouse or partner, were more involved in social and religious groups, and generally had better health, among other differences.
The average age of the nurses who answered the gratitude questions was 79, and by the end of 2019, 4,068 of them had died. After accounting for a variety of factors, such as the median household income in their census tract, their retirement status, and their involvement in a religious community, Chen and her colleagues found that nurses with the most gratitude were 29% less likely to have died than nurses with the least gratitude.
They then looked deeper into the study, controlling for a range of health issues, including a history of heart disease, stroke, cancer and diabetes. The risk of death for the most grateful women was still 27% lower than for the least grateful women.
When researchers accounted for the effects of smoking, alcohol consumption, exercise, body mass index and diet quality, the risk of death for the most grateful nurses remained lower, at 21%.
Finally, Chen and colleagues added measures of cognitive function, mental health and psychological well-being. Even after accounting for those variables, mortality risk was 9% lower for nurses with the highest gratitude scores.
The findings were published Wednesday in JAMA Psychiatry.
Although the study shows a clear link between gratitude and longevity, it doesn't prove that one causes the other. While it's plausible that gratitude helps people live longer, it's also possible that being healthy inspires people to feel grateful, or that both are influenced by a third factor that wasn't accounted for in the study's data.
Sonja Lyubomirsky, an experimental social psychologist at UC Riverside who studies gratitude and was not involved in the study, said she suspects all three are at play.
Another limitation is that all of the study's participants were older women and 97 percent of them were white. It's not known whether the results would extend to a more diverse population, Wong said, “but based on theory and research, I don't see any reason why they wouldn't.”
The Harvard team noted that gratitude can have its downsides: If it is linked to feelings of indebtedness, it can undermine a sense of autonomy or accentuate a hierarchical relationship. Lyubomirsky added that it can make people feel like a burden to others, which is particularly dangerous for someone with depression who is having suicidal thoughts.
But in most cases, gratitude is an emotion worth cultivating, Lyubomirsky said. Clinical trials have shown that gratitude can be enhanced through simple interventions, such as keeping a gratitude journal or writing a thank-you letter and delivering it by hand.
“Gratitude is a skill that can be developed,” he said.
And, like diet and exercise, it appears to be a modifiable risk factor for better health.
Lyubomirsky found that teens randomly assigned to write thank-you letters to their parents, teachers or coaches resolved to eat more fruits and vegetables and cut back on junk and fast food — behavior not shared by their classmates in a control group. Perhaps after reflecting on the time, money and other resources invested in them, the teens were inspired to protect that investment, she said.
More research will be needed to see if interventions like these can prolong people's lives, but Chen is optimistic.
“As evidence accumulates, we will better understand how to effectively enhance gratitude and whether it can significantly improve people's long-term health and well-being,” she said.
