“We can do so much better for having a long healthy life by pretty simple minimal changes in our behavior, and only 8% of adults in our country are adhering to these,” he said. “The main take-home message is that there’s huge gains in health and longevity to be had just by simple changes in our behavior pattern, and as a country, I think we need to make it easier for ourselves to do this by promoting tobacco cessation, by providing better environments for physical activity and so on.”
The ‘surprising’ impact of behaviors on longevity
After analyzing the data, the researchers found that, in 2014, the overall projected life expectancy at age 50 was to live 33.3 more years for women and 29.8 more years for men.
Yet among the adults who reported that they adopted all five healthy lifestyle factors, the researchers found, they lived 43.1 more years among women and 37.6 more years among men.
Among those adults who reported that they adhered to none of the five healthy lifestyle factors, the researchers found that they lived only 29 additional years among women and 25.5 additional years among men.
“To me, the surprising outcome was how strong it was: what a big impact these simple behaviors could have on life expectancy,” Stampfer said. “I was surprised that it was that pronounced.”
Among the women, on average, about 30.8% of the life expectancy at age 50 that they gained from adopting five, versus zero, of those lifestyle factors was attributed to a reduced risk of cardiovascular disease death; 21.2% was attributed to a reduced risk of cancer and 48% to other causes of death.
Among the men, those percentages were 34.1% attributed to a reduced risk of cardiovascular disease death, 22.8% attributed to a reduced risk of cancer and 43.1% to other causes.
The study had some limitations, including that the data on adherence to the five lifestyle factors were all self-reported, making outcome vulnerable to measurement errors.
Also, the data analysis did not include measures of certain health conditions that are risk factors for a shorter life expectancy, such as diabetes or high blood pressure.
That limitation, however, “is both a strength and a limitation, in a way … because what we’re estimating here is the prolongation of life expectancy just based on behaviors,” Stampfer said.
“Obviously, it’s much better to do these healthy behaviors from childhood, really, but if you’re beyond age 50, beyond age 60, beyond age 70, it’s not too late,” he added.
The factor that was seen as more ‘powerful’
Though the study highlighted how the combination of all five lifestyle factors could help prolong life expectancy, Vaughan pointed out how each individual factor also was tied to a reduced risk of premature death.
“It looks like cigarette smoking has a more powerful effect than the other lifestyle changes or behaviors. Certainly, maintaining a reasonable body-mass index is a great way to protect oneself against the development of diabetes,” Vaughan said.
“So, in aggregate, we see the effect on longevity, but you can imagine it’s largely through effects on cardiovascular risk and metabolic risk,” Vaughan said. “It suggests potentially at a defined point in life, say age 50, if you adhere to a healthy paradigm like this, you can have an impact on your longevity and on your health span.”
“Beyond cancer risk, smoking contributes to lung disease, heart disease and diabetes. The study shows that even minimal smoking — from one to 14 cigarettes a day — is associated with increased death due to cancer and heart disease,” said Der-Sarkissian, who was not involved in the new study.
As for some of the other lifestyle factors, “getting weight below a BMI of 30 appears to help considerably, according to the study. A higher body weight is linked to increased risk of diabetes and cancer, among other obesity-related conditions,” he said. “The study suggests physical activity of at least 30 minutes a day of moderate or vigorous activities, including brisk walking.”