Now that you have to be at least 21 to buy cigarettes in Maine, can we expect teenagers to add “quit smoking” to their summer bucket lists?

Maybe not, but evidence indicates that the change in the law will lead to less smoking among Maine’s teenagers.

We can look to the town of Needham, Massachusetts, which raised the legal sales age for tobacco from 18 to 21 over course of three years, from 2005 to 2008. An analysis found that smoking among high school students fell significantly, from 13 percent to 7 percent. Cigarette purchases among smokers also dropped. Both declines exceeded those in 16 counties the researchers used as a comparison, where the legal age to buy tobacco was younger than 21.

Cigarettes for sale in 2009 at The Cigar & Smoke Shoppe in Bangor. Gabor Degre | BDN

Needham is among more than 200 municipalities that have raised the legal tobacco-buying age. Portland is another, becoming the first Maine city to take that step last June. It’s still too early to determine the impact of Portland’s ordinance, but city officials say the effects will likely show up in the youth smoking rates for 2017.

So-called “Tobacco 21” policies are now catching on at the state level, with Maine becoming the fourth state to pass such a law, behind Hawaii, California and New Jersey.

Part of the reason for the growing momentum is that almost everyone who becomes a smoker picks up the habit while they’re young. Ninety percent of daily smokers started before their 19th birthday, according to a 2015 report by an Institute of Medicine committee. If teenagers can’t legally buy tobacco until they’re no longer teenagers, the thinking goes, many will never pick up the habit in the first place.

REUTERS | Jason Reed | File Photo

The IOM committee, using two different simulation models, projected that increasing the minimum tobacco purchase age to 21 would lead to a 12 percent decrease in smoking prevalence. The biggest impact would be seen among teens aged 15 to 17, according to the report.

If the tobacco purchase age was raised to 21 nationwide — purely a hypothetical, since federal law prohibits the FDA from doing so — there would be “approximately 223,000 fewer premature deaths, 50,000 fewer deaths from lung cancer, and 4.2 million fewer years of life lost for those born between 2000 and 2019,” the IOM report states.

Much of the opposition to Tobacco 21 policies are rooted in arguments about personal freedom. In his veto of the Maine legislation — which lawmakers later overrode — Gov. Paul LePage called the policy an “attempt at social engineering.” It denies 18-year-olds the right to purchase a legal product while they’re otherwise treated as adults under the law, with rights to vote, serve in the military, marry, and pay taxes, he wrote in his veto message.

The law doesn’t prohibit people younger than 21 from smoking, but from buying tobacco and electronic smoking devices. It takes effect on July 1, 2018, though it includes a provision that those aged 18 or older on that date can still buy tobacco. So, the law really kicks in when those people turn 21 in 2021.

LePage also argued that the law will fail from a public health standpoint. He cited CDC data showing that four times as many high schoolers drink than smoke cigarettes. “The fact that the legal age to purchase and consume alcohol is 21 everywhere in the country while the legal age to purchase tobacco is 18 in most of the country demonstrates this legislation will not achieve its stated purpose,” he wrote.

I *think* the logic there is that if raising the legal age actually prevented kids from consuming unhealthy substances, then the drinking rate among high schoolers should be lower. But many other factors beyond the legal age affect those numbers — the teen smoking rate is already at historic lows.

Even so, any smoking among teenagers is too much, public health advocates say.