Investigating The Impact Behavioral Factors Have On Life Expectancy
July 9, 2014

Investigating The Impact Behavioral Factors Have On Life Expectancy

redOrbit Staff & Wire Reports - Your Universe Online

Eating healthy, being physically active, limiting alcohol consumption and avoiding cigarettes could add 10 years to your life, public health physicians from the University of Zurich report in what is being called the first study to ever investigate the impact of behavioral factors on life expectancy in numbers.

Writing in a recent edition of the journal Preventive Medicine, lead author Eva Martin-Diener of the university’s Institute of Social and Preventive Medicine (ISPM) and his colleagues examined the impact of the World Health Organization’s four behavioral risk factors for non-communicable diseases on a person’s life expectancy.

Each of the factors (smoking, alcohol, poor diet and inactivity) were analyzed both individually and combined, allowing them for the first time to depict the consequences of an unhealthy in numbers. The study authors looked at over 16,000 individuals who participated in two Swiss population studies from between 1977 and 1993, assessing smoking status, alcohol consumption, physical activity level and diet at baseline.

They discovered that a person who smokes, drinks a lot, tends to be physically inactive and has an unhealthy diet has a mortality rate that is 2.5 times higher in epidemiological terms than a person who is health-conscious, the authors said. In fact, a healthy lifestyle “can help you stay ten years’ younger,” Martin-Diener said in a statement.

GET FIT WITH FITBIT - Fitbit Flex Wireless Activity + Sleep Wristband, Black

She and her fellow investigators used information from the Swiss National Cohort (SNC) for their research, and focused their efforts on cardiovascular diseases and cancer, which are the primary causes of death in Switzerland. They then correlated data on tobacco use, fruit consumption, exercise and alcohol consumption from 16,721 individuals between the ages of 16 and 90, tracking corresponding deaths through the year 2008.

The effect of the four types of behavior was still visible when biological risk factors such as weight and blood pressure were accounted for, the study authors noted. Hazard ratios for the combination of all factors combined ranged from zero to 2.41 (1.99–2.93) in men and 2.46 (1.88–3.22) in women.

Furthermore, for 65-year-old men, the probability for surviving the next 10 years was 86 percent for those with no other risk factors and 67 percent for those with all four. For women, the numbers were 90 percent and 77 percent, respectively. In 75-year-olds, the probabilities were 67 percent and 35 percent in men, and 74 percent and 47 percent in women.

“The effect of each individual factor on life expectancy is relatively high,” said Martin-Diener. Of the four, however, smoking appeared to be the most harmful. When compared to a group of non-smokers, tobacco users have a 57 percent increased risk of premature death, while each of the other four factors (unhealthy diet, lack of exercise and alcohol abuse) resulted in an elevated mortality risk of approximately 15 percent per factor.

“We were very surprised by the 2.5 fold higher risk when all four risk factors are combined,” added fellow investigator and ISPM colleague Brian Martin. The research was financially sponsored by the Swiss Heart Foundation and the Swiss Cancer League.

Image 2 (below): Charts for probabilities of surviving the next 10 years for 65 and 75-year-olds with differing health behaviour. Legend: e. g. box top right: a 75-year-old man today who at the start of the study smoked, drank a lot and hardly ate any fruit has a 35 percent probability of surviving the next ten years. E. g. box bottom left: a 65-year-old woman with positive health behaviour in all four areas has a 90 percent probability of still being alive in ten years’ time. Credit: Preventive Medicine/UZH