On February 24, 2015 BioMed Central published a study by the Australian National University entitled, “Tobacco smoking and all-cause mortality in a large Australian cohort study: findings from a mature epidemic with current low smoking prevalence”. The study of more than 200,000 people, published in BMC medicine, found about 67 percent of smokers perished from smoking-related illness. That rate is higher than doctors previously estimated.

• Tobacco smoke can boost the risk for least 13 types of cancer. The earlier you quit, the better.  “The relative risks of adverse health effects increase with increasing intensity of smoking,” the study states, “measured by the amount of tobacco smoked per day, and with increasing duration of smoking.”
• Smoking 10 cigarettes daily doubles the risk of death, the research showed. Smoking a pack daily quadruples it.
• An estimated 42.1 million Americans smoke cigarettes, according to the Centers for Disease Control and Prevention. Cigarette smoking is the top cause of preventable disease and death in the United States, the agency reports, accounting for more than 480,000 deaths every year — or one in five.

• An Ohio State University study found employees who smoke tobacco cost employers roughly $6,000 more annually in health care and productivity than nonsmokers.
• Another study, from the New England Journal of Medicine, shows health-care costs for smokers tend to be, on average, 40 percent higher or $6,000 more than a nonsmoker (The same research darkly suggests we’d all save money in the short term if cigarettes vanished from earth but might pay more down the line because everyone would live longer.)
• In 2003, the World Health Organization issued a report recommending enforcing smoke-free public places and creating “supportive environments” for people to part with their packs. See http://www.who.int/tobacco/resources/publications/tobacco_dependence/en/

You can read more about this BioMed Central study at ARS Technica.