Tobacco laws for youth may reduce adult smoking

The researchers discovered that states with more restrictive limits on teens purchasing tobacco also have lower adult smoking rates, especially among women. And compared with states with less restrictive limits, they also tend to have fewer adult heavy smokers.

The study is published online June 13 in the American Journal of Public Health.

"In most states for many years, it has been illegal to sell cigarettes to people under 18, but few provisions are in place to prevent those sales," said the study's first author Richard A. Grucza, PhD, associate professor of psychiatry. "This study shows that more restrictive policies can prevent teen smoking and be beneficial down the road."

Grucza's team evaluated data from an ongoing National Cancer Institute survey that monitors smoking behavior in all 50 states.

Studying information gathered from 1998 to 2007 from 105,519 individuals ages 18 to 34, the researchers looked at whether people ever had smoked, whether they currently were smoking, and, if they did smoke, whether they smoked more than 10 cigarettes per day.

They also looked at the smoking restrictions in place in states when the study subjects were 17 years old.

"We looked at age 17 because in most states, it was illegal for anyone under 18 to buy tobacco products," Grucza said.

But how individual states chose to enforce the laws varied. Grucza's team focused on nine smoking-related policies and found that in states with enforcement policies, not only did 17-year-olds have more difficulty purchasing cigarettes, but that when they reached their 20s or 30s, they were less likely to smoke.

"We estimated that if all states had effective policies in place, it would reduce the prevalence of smoking by about 14 percent and the rates of heavy smoking by 29 percent," he said.

The four most effective restrictions included those on cigarette vending machines, in which the machines either were eliminated or housed in locations inaccessible to those under 18; identification requirements for purchasing cigarettes; restrictions on repackaging cigarettes so that five or 10 could be sold at a time, rather than an entire 20-cigarette pack; and prohibiting distribution of free cigarettes at public events.

Because cigarettes have been regulated by the U.S. Food and Drug Administration (FDA) since 2009, many of the more restrictive policies are in effect nationally, so Grucza's team believes future smoking rates among adults may decline at least partly as a result of those policies.

Interestingly, they found the policies to restrict youth access to tobacco had a big impact on women but didn't seem to influence smoking rates in men.

"We can only speculate about why, but a number of past studies have shown that underage women and girls often have an easier time getting alcohol or tobacco than underage men," Grucza said. "We suspect that policies like those that require checking IDs may have evened things out by making it just as difficult for underage women to buy cigarettes as it is for underage men."

As more states around the country implement and enforce more restrictive policies, Grucza expects they may further reduce smoking rates.

"A lot of states still have not adopted all of these policies," he explained. "In 2006, which is the last year for which we have data, only four states required a photo ID, and only 20 states had any kind of identification requirements at all. So there's still a lot of room for improvement."

Grucza said some states are considering restricting youth access even more. In New York, there is a proposal to raise the age for tobacco purchases to 21. Meanwhile, in Alabama, Mississippi, Alaska and Utah, the minimum age for tobacco purchases already has been raised to 19.

Funding for this research comes from the National Institute on Drug Abuse and the National Cancer Institute of the National Institutes of Health (NIH). It also was supported by grants from the American Cancer Society and the American Foundation for Suicide Prevention. NIH grant numbers: R21 DA0266, R01 DA031288, R01 DA0269112, T32 DA07313, K01 DA025733, K02 DA021237 and P01 CA89392.