In a study published in JAMA Pediatrics this week
, researchers wanted to pin down
relationship. They used national data from the U.S. Bureau of Labor Statistics' National Longitudinal Survey of Youth to analyze the effect that smoke-free laws had on individual smoking behaviors of 4,098 teens and young adults from 1997 to 2007.
Smoke-free laws for public spaces were initially enacted to prevent secondhand smoke exposure, researchers say. Bans on smoking in the workplace, restaurants and bars, as well as increased cigarette taxes, have all reduced the chances of young people taking up smoking, the study says.
"Since smoking initiation typically occurs before youth enter the workplace, smoke-free workplace laws likely affect smoking initiation by showing kids that adult smoking norms reject smoking," said Anna Song, one of the study's authors and a health psychology professor with the University of California-Merced Health Sciences Research Institute
. "The findings show us that public policy is one of the most powerful tools in curbing youth smoking."
Previous studies have provided a snapshot showing the relationship between smoking laws and youth smoking behaviors, but researchers involved with this study say it's the first one following young people over time to demonstrate the effects that smoke-free laws and state taxation have on smoking.
Starting in 1997, individual smoking behaviors of the participants ages 12 to 18 were recorded every year. Initially, participants were asked if they had ever smoked a cigarette; then in annual follow-up interviews, participants were asked how many days they smoked within the previous 30 days. Smoke-free laws at the state, county and city levels were reviewed and correlated with participant smoking behavior. The effects of state level cigarette taxation on smoking trends was also taken into consideration.
Throughout the country, the study found that where smoke-free workplace laws were in effect, the odds of youth starting to smoke were reduced by roughly 34%.
Other findings were consistent with earlier studies: Male youth participants in the study were more likely to start smoking than females, black youth had lower odds of starting to smoke than non-Hispanic white youth, and the odds of being a smoker decreased as socioeconomic levels increased, according to the study -- but those factors had less impact than the smoke-free laws.
"We found the effect of smoke-free laws to have a considerably stronger effect on reducing the the odds of smoking across the board, even more so than socioeconomic factors," said Song.
In areas that already had smoke-free bar laws in place in 2007, young people were 20% less likely to be smokers, while current smokers smoked 15% fewer days per month than youth not covered by such laws, the study found.
The Campaign for Tobacco-Free Kids reports
every 10% increase in the price of cigarettes reduces the number of young-adult smokers by 3.5%.
"Smoke-free workplace laws have the most powerful effect on smoking initiation, equivalent to the deterrent impact of a $1.57 tax increase," said Stanton Glantz, senior researcher on the study, a professor at University of California-San Francisco and tobacco control activist.
The data ended in 2007 before e-cigarettes took off, the researchers say. The study did not examine the effects of e-cigarettes
Figures for 2014 from the Centers for Disease Control and Prevention
indicate that cigarette smoking kills more than 480,000 people annually in the United States, with more than 42,000 of these deaths coming from secondhand smoke exposure. The medical costs associated with smoking-related illness in the United States can be upward of $300 billion a year, according to the CDC.
"When it comes to these smoke-free policies, I hear it all the time from the general public: 'Here's another law telling me what I can't do.' However, if you knew you were saving lives, would you do it?" asked Song. "Sure, it's inconvenient to save lives, but, look at the good it is doing."