What leads to a longer life? Despite life expectancy growing dramatically in the last century, not all countries have seen a similar increase despite on the surface similar levels of affluence. One example is that of Americans who have a shorter life expectancy compared with residents of almost all other high-income countries. Lifestyle factors are the likely explanation for this.
To see how lifestyle factors can affect mortality and life expectancy, United States researchers looked at lifestyle data from over 120,000 men and women who were followed for up to 34 years. The average age of the men was 55 years, and for women, it was 47 years. Lifestyle and health questionnaires were administered every two or four years.
The big five healthy habits
The researchers were interested in five healthy habits to see how they translated into mortality and life expectancy. The habits were never smoking, having a healthy body weight, being active for at least 30 minutes each day, eating a high-quality diet, and drinking only a moderate amount of alcohol intake of one glass of wine each day for women and two glasses for men.
Ticking the box of all five healthy habits was linked to an 82 per cent lower risk for dying from cardiovascular disease, a 65 per cent lower chance of dying from cancer, and a 74 per cent lower risk of dying from all causes during the time the study ran.
Translating these numbers into years lived, for someone of 50 years of age, would mean an extra 14 years of life for women and 12 years for men if they had all five healthy habits compared to having none.
Even having just one of the five healthy lifestyle behaviours was associated with a longer lifespan. Each factor prolonged life expectancy around two to three years.
The clear deficiency of the study was its observational design which cannot prove the lifestyle habits were the cause of any change in mortality, although there is a strong link as to why they should factor. The use of self-reporting of lifestyle habits also can introduce bias where people are known to over-report healthy habits and under-report unhealthy habits.
Implications
Adopting a healthier lifestyle need not be hard with this study highlighting that even a small improvement in lifestyle could give longer years of life no matter where in the world a person lives.