"The addicted mind justifies some crazy things," said Matt Murphy. The 19-year-old got hooked on nicotine in high school, and what began as experimentation with vaping turned into an addiction.
"That snowballed into me having a neurochemical dependency on it without me even knowing," he said.
His addiction followed him to college: "I would be studying in the library and I would have to bike back to the dorm, like, every 20 minutes."
E-cigarette use among middle and high school students is rising sharply. In 2018 nearly five percent (or one in 20) middle school students reported trying e-cigarettes within the last 30 days. That's up from less than 1 percent in 2011.
Among high schoolers, that number jumped from 1.5% in 2011 to more than 20% in 2018.
And that kind of jump has doctors and health officials concerned.
"Nicotine is one of the most addictive chemicals known to man," said Dr. Sharon Levy. "And we know that some kids are getting addicted with really just a handful of uses. Nicotine can interfere with memory and can interfere with learning, particularly in younger individuals."
Eighteen-year-old high school senior Sarah Ryan said she knows very few young people who haven't been exposed to this issue, whether through themselves or through their friends. "These products are used by kids at every age," she said.
She calls herself an anti-tobacco and vaping activist, who wants the legal age to buy these products raised to 21. "These products shouldn't be a part of high school culture," she told CBS News medical contributor Dr. Tara Narula. "And 18-year-olds are still in high school. So, if the age to purchase tobacco was 18, then it has a bigger influence in a younger set of people. Because even if you're not 18, and you're 16, you hang out with 18-year-olds. And those 18-year-olds might be using the product."
Dr. Narula asked, "Why do you think it's been so hard to get this kind of legislation passed in the rest of the country?"
"I think that there's just the same arguments about, 'Well, if you're old enough to die for your country, why can't you buy a cigarette, or smoke or vape or whatever have you?'" Ryan replied.
But that is beginning to change. Nine states have passed legislation to raise the legal age for tobacco and vaping products to 21, and hundreds more cities, counties and towns have as well.
The latest state to do so is Illinois; yesterday, Gov. J.B. Pritzker signed a bill increasing the limit from 18 to 21.
And on Thursday, Congressman Robert Aderholt (R-Ala.) introduced a bill that would make 21 the legal age nationwide, the Stopping Consumption of Tobacco by Teens (SCOTT Act).
Dr. Levy said, "The younger you are when you start using a substance, the more vulnerable you are to becoming addicted. And that's because as the brain develops, it just becomes a little bit more resistant to the neurologic changes that are associated with addiction."
Matt Murphy kicked his habit nine months ago, and has become an anti-nicotine advocate himself. His biggest message to teens thinking of vaping? "It is way easier to prevent than it is to stop," he said. "If you never dig yourself a hole, you never have to climb out of the hole. Just don't start digging."
Juul, which makes up about 75 percent of the U.S. e-cigarette market, told CBS News it "strongly supports" raising the buying age for tobacco and vaping products to 21. Juul said one of the biggest problems is sharing by legal-age peers.
The company said it will continue to work with lawmakers to reduce youth-use rates.