'Teens who feel 'too fat' light up cigarettes to slim down'

Overweight and obese teens smoke cigarettes to lose weight, countering the general assumption that they light up simply because they are addicted to nicotine, a new study has found.

According to the researchers from the Cornell University in the US, 46 per cent of girls and 30 per cent of boys smoke in part to control their weight among US teens who are frequent smokers.

Smoking to lose weight is significantly more common among teens who feel they must slim down. Girls who said they were 'much too fat' were nearly 225 per cent more likely to smoke to lose weight than girls who said their weight was about right.

For boys, being overweight was less of a predictor for smoking, perhaps because they feel less pressure from society to lose weight than girls do.

Even so, boys who said they were 'much too fat' were nearly 145 per cent more likely to smoke for weight loss than boys who said their weight was about right.

"This helps us better understand why people choose to engage in risky health behaviours. It is not always just about the immediate pleasure or enjoyment; sometimes it is a means to another end," said John Cawley, professor at Cornell.

Teen smoking is a particularly worrisome public health concern, because people who start smoking by their early 20s are likely to continue in adulthood. "One hundred years ago, what we mostly died of were infectious diseases, like tuberculosis and influenza. Now we die from our own choices," said Cawley.

"At all levels of government, there is a realisation that we need to find ways to stop teenagers from developing poor health habits," Cawley said.

Researchers analysed data from the Health Behaviour in School-aged Children survey from 2001-01 and 2005-06 of nearly 10,500 US school children who were 11, 13 or 15 years old.

The children reported their heights and weights, which the researchers used to calculate their body mass indexes. The youth also reported their perception of their weight.

When asked 'Do you think your body is ... ,' they responded with either 'much too thin', 'a bit too thin', 'about right', 'a bit too fat' or 'much too fat'.

The survey also asked the children whether they had done anything to lose weight, what that action was and whether they smoked and how frequently. Researchers also found that white teens were more than twice as likely as African-American adolescents to smoke for weight loss.

The findings have implications for anti-smoking policies, Cawley said. "If you can break the perceived connection between smoking and weight loss, you may increase their responsiveness to cigarette taxes," said Cawley.

The study appears in the journal Health Economics.