NEW YORK (WCBS 880) — According to the National Center on Addiction and Substance Abuse at Columbia University, 90-percent of Americans suffering from addiction started using before the age of 18.

“Adolescent substance use is America’s number one public health problem,” said Susan Foster, who conducted a study of 1,000 American teens for the Center. “It’s a huge, huge public health problem of epidemic proportion.”

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Alcohol is the most abused followed by cigarettes, marijuana and prescription drugs.

“Sometimes we minimize it. We say ‘Oh well, at least they’re only using alcohol. They’re not using cocaine’,” Foster said.

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The study found 46-percent, or 6 million U.S. high school students use these substances.

“One of the most striking findings is that one in eight adolescents, these are high school-age teens, already have the disease of addiction,” she added.

“It interferes with brain development and it heightens dramatically the risk of addiction,” Foster said.

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