CLEVER children are twice as likely to smoke cannabis as teenagers due to their curious minds and students who were high academic achievers at 11 are also more likely to drink alcohol in their teens, according to a nine-year study by University College London.
Experts examined data for more than 6,059 people from 838 state and 52 public schools across England and found that bright children are less likely to smoke cigarettes as teenagers but more likely to smoke cannabis.
This could be because middle-class parents pay more attention to health warnings about cigarettes, which they pass on to their children.
But clever children are more likely to smoke cannabis in their late teenage years because they have greater curiosity and strive to be accepted by older people.
Researchers added that clever children are "initially cautious of illegal substances in early adolescence as they are more aware of the immediate and long-term repercussions that breaking the law may incur than those with lower academic ability."
Scientists studied the academic achievement of children at 11 and compared it with their behaviour during early adolescence, 13-17, and then late adolescence, 18-20.
During their late teenage years, clever children were more than twice as likely to drink alcohol regularly and persistently. Meanwhile, clever pupils were 50 per cent more likely to use cannabis occasionally and nearly twice as likely to use it persistently than their less gifted peers.
These patterns persisted into adulthood and appear to contradict the notion that academic prowess was associated with a greater tendency to ''experiment'' temporarily.
The study was published in the journal BMJ Open. However, Dr James Williams at UCL Medical School said there has been a general downward trend in smoking cannabis and drinking alcohol among teenagers.
- The Daily Telegraph, London