The "Just Say No" generation was often told by parents and teachers that intelligent people didn't use drugs. Turns out, the adults may have been wrong.

A new British study finds children with high IQs are more likely to use drugs as adults than people who score low on IQ tests as children. The data come from the 1970 British Cohort Study, which has been following thousands of people over decades. The kids' IQs were tested at the ages of 5, 10 and 16. The study also asked about drug use and looked at education and other socioeconomic factors. Then when participants turned 30, they were asked whether they had used drugs such as marijuana, cocaine and heroin in the past year.



Researchers discovered men with high childhood IQs were up to two times more likely to use illegal drugs than their lower-scoring counterparts. Girls with high IQs were up to three times more likely to use drugs as adults. A high IQ is defined as a score between 107 and 158. An average IQ is 100. The study appears in the Journal of Epidemiology and Community Health.

The lead researcher says he isn't surprised by the findings. "Previous research found for the most part people with high IQs lead a healthy life, but that they are more likely to drink to excess as adults," says James White a psychologist at Cardiff University in the United Kingdom.

It's not clear why people with high childhood IQs are more likely to use illegal drugs. "We suspect they may be more open to new experiences and are more sensation seeking," says White. In the paper, White and his co-author also mention other studies that find high IQ kids may use drugs because they are bored or to cope with being different.

That seems to ring true for one of my childhood classmates. Tracey Helton Mitchell was one of the smartest kids in my middle school. But, by the time she was in her early 20's, Tracey was a heroin addict. I found out while flipping channels one sleepless night and stumbled upon the documentary "Black Tar Heroin."

"I was confident in my abilities but there was a dissonance," says Tracey, with whom I recently reconnected. "No matter what I did, what I said, where I went, I was never comfortable with the shell I carried called myself."