The study, which collected 34 years' worth of data, found that life expectancy for people aged 50 years increased by 14.0 and 12.2 years for female and male adults respectively, compared with individuals who adopted zero low-risk lifestyle factors.
"Adopting a healthy lifestyle could substantially reduce premature mortality and prolong life expectancy in USA adults", the study said. These factors are not smoking, eating a healthy diet, regularly exercising, keeping a healthy body weight, and moderate alcohol consumption.
For women this meant on average an extra 14 years of life, and for men an extra 12 years, with the combination of all five healthy behaviors linked with the most additional years of life gained.
America is one of the wealthiest countries worldwide, yet Americans have a shorter life expectancy compared with other high-income countries, including Japan, Canada and Norway.
"Adopting a healthy lifestyle could substantially reduce premature mortality and prolong life expectancy in USA adults", the authors write. In fact, in 2015 the United States ranked 31st for life expectancy at birth among all the countries in the world, notes CBS, citing the World Health Organization.
Stampfer and colleagues identified the five healthy habits as having a body mass index of between 18.5 and 25, engaging in at least 30 minutes of moderate exercise daily, not smoking, drinking up to only one 150ml glass of wine daily for women, and two for men; and a diet low in saturated fats, sugar and red meat but rich in vegetables, fruits, and whole grains.
The study is the first comprehensive analysis of the impact that adopting low-risk lifestyle factors has on life expectancy in the U.S. It will be published online today in Circulation.
To prove that the study is valid, researchers were searching for the connection between the five life habits and premature death after acquiring data from the national Nurses' Health Study and the Health Professionals Follow-Up Study. They found that following the five healthy habits above can reduce the overall risk of death by 74 percent, the risk of death from heart disease by 82 percent, and the risk of death from cancer by 65 percent.
Only eight percent of Americans are now following the healthy habits underlined in the study, research co-author Dr. Meir Stampfer, a professor of medicine at Harvard, told CNN.
"Public policies should put more emphasis on creating healthy food, built, and social environments to support and promote healthy diet and lifestyles".