In the US, Life expectancy at birth in 2009 is 78.5 years.
World Health Organization (2011). Global Health Observatory
From 1900 through 2004, life expectancy at birth increased
from 46 to 75 years for men and from 48 to 80 years for women.
U.S. Dept of Health and Human Services, Centers for Disease
control and Prevention, National Center for Health Statistics,
Health, United States, (2007).
for long periods may decrease your lifespan. Unfortunately, most
people remain seated for a great portion of their day. The more
time you spend seated throughout the day, the greater your risk
for dying from all causes, presumably even if you do exercise
regularly. Reducing time seated to less than three hours a day
could add two years to one's life expectancy at birth on average.
Katzmarzyk PT, Church TS, Craig CL, Bouchard C (2009).
Sitting time and mortality from all causes, cardiovascular disease,
and cancer. Med Sci Sports Exerc. 41(5):998-1005.
Katzmarzyk PT, Lee I-M (2012). Sedentary behaviour and
life expectancy in the USA: a cause-deleted life table analysis.
BMJ Open. 2:e000828.
A lack of leisure-time physical activity accounts for an estimated
0.9 years of life expectancy at birth in Canada.
Katzmarzyk PT (2006). Physical inactivity and life expectancy
in Canada. J Phys Act Health. 3, 381.
In the US, Smoking is associated with 2.5 and 1.8 years of
life expectancy at birth in men and women, respectively.
Danaei G, Rimm EB, Oza S, et al. (2010) The promise of
prevention: the effects of four preventable risk factors on national
life expectancy and life expectancy disparities by race and county
in the United States. PLoS Med, 7.