"Oh, I've tried to quit three or four times at least ... mostly New Year's resolutions that don't pan out," said Smart.
He may have triggered a nicotine addiction when he started smoking at age 15.
"If you begin smoking when you're a teenager, you often have higher levels of lifetime dependence," said Geneticist Robert Weiss, PhD.
Doctor Weiss and his team at the University of Utah found that 60 percent of people have a genetic variance that makes them susceptible to nicotine addiction. Those who started smoking at 16 or younger, and had two copies of the variance, triggered a lifelong dependence. That's about one of every eight smokers.
The study is proof anti-smoking campaigns need to reach kids as early as elementary school.
"It reconfirms that those who start before get addicted to nicotine more easily than those who start later in life, so if we can get to them when they're young, they won't start when they're older," said David Neville, Media Coordinator.
Brandon wants the anti-smoking campaign to succeed for two very important reasons.
"I have two children of my own and I'm concerned for them and the genetic link that may be there," said Smart.
It may be in their genes, but the next generation can fight it by never picking up a cigarette in the first place.
Nearly 6,000 children under 18 start smoking every day, and 4.5 million kids are smokers.
Now that researchers have established a genetic link between nicotine addiction and teenage smokers, they're working on quitting methods that target genes.
- Get more L.A. breaking news, weather, traffic and sports
- Have a news tip? Send your tips, video, or pictures