KNOXVILLE, Tenn — Drug addictions have to start somewhere.
"I've never had anyone who said that heroin was the first drug that they ever tried or used," said Hilde Phipps.
Phipps is the Senior Director of Outpatient Substance Use and Specialty Services at Helen Ross McNabb.
She said addiction starts with a gateway drug. That's any habit-forming substance that may lead to the use of other addictive drugs.
"Somebody is taking a substance to change the way they feel," said Dr. Mark McGrail, Director of of Addiction Medicine at Cherokee Health Systems.
The million dollar question among doctors - is marijuana a gateway drug?
The Centers for Disease Control succinctly said no in that most people who use marijuana do not go on to use other, 'harder' substances, and others agree.
"For the majority of folks, I would say no," said McGrail.
He works with patients who deal with different drug addictions.
"Not everybody who smokes marijuana goes on to develop either a substance abuse disorder or use another illicit substance"
The National Institute on Drug Abuse reports that same thing.
But what about the marijuana users who did go on to develop a stronger addiction?
The National Survey on Drug Use and Health reports people who are addicted to marijuana are three times more likely to be addicted to heroin.
"For people who have some other risk or predisposition to addiction, I would say that very often marijuana is the first substance used," said McGrail.
In cases like that, marijuana could be called a gateway drug.
Doctors said your home life, peers, family environment, and genetics all play in to if it will lead to a stronger addiction.
But weed isn't the only thing that may make your brain likely to respond to other drug.
"I think our two biggest gateway drugs in this country are tobacco and alcohol," said McGrail. "We don't tend to look at tobacco and alcohol because they're quote legal as gateway drugs, but that's where most people start."
And people start pretty young.
"The age of first use is generally 12 and that's of any substance," said Phipps.
That's because gateway drugs are often what people find laying around the house, which in many states now includes pot.
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"It'll be on the night stand, it'll be in the kitchen cabinet because well in that state you can do that," said McGrail.
Addiction specialists said for many people, using marijuana, cigarettes or alcohol don't lead to harder drug use, especially if they're adults.
"Really it would be ideal if they delay until around age 25 when the prefrontal cortex is fully developed in the brain and then the likelihood of having a problem with substances or becoming addicted is reduced dramatically," said Phipps.
So, is marijuana a gateway drug? It's going to depend on the person, as different drugs affect people different ways
It all depends on who you are, as well as the choices you make.