Teen smokers are more likely to experience obesity as adults

Remember the cool girls, huddled together in high school restrooms, puffing their cigarettes?

Well, here's consolation for the nerds in the crowd: Those teen smokers are more likely to experience obesity as adults, according to a new study from Finland.

Girls who smoke 10 cigarettes per day or more are at greatest risk, particularly for abdominal obesity. Their waist sizes are 1.34 inches larger than nonsmokers' waists are as young adults, according to the study in the February 2009 issue of the American Journal of Public Health .

But smoking in adolescence did not necessarily predict weight problems for men, according to the study.

Scientists know a correlation exists between women's weight and smoking, said lead study author Suoma Saarni, a researcher with the Department of Public Health in Helsinki.

However, she added, "We do not know why smoking did not affect men's weight, as we do not know why smoking affected women's weight."\

The study followed twins born between 1975 and 1979 with questionnaires mailed shortly after their 16th birthdays. Researchers collected more data on the 2,278 women and 2,018 men when the twins were in their 20s.

Scientists looked at twins to take into account familial or genetic factors affecting smoking and weight gain, Saarni said. Half of the participants had never smoked, and 12 percent were former smokers in adolescence. About 15.5 percent of men and 9.4 percent of women smoked at least 10 cigarettes daily.

By the time participants reached their 20s, weight problems became evident. By age 24, roughly 24 percent of men and 11 percent of women were overweight. However, male smokers were not necessarily more prone to become overweight than nonsmokers.

The young women who smoked more than 10 cigarettes per day were 2.32 times more likely to become overweight than nonsmokers, according to the study.

The difference could be either biological or cultural, Saarni said. Biologically, it might be that tobacco and gender specific hormones interact differently in girls and boys in ways that affect appetite and fat distribution.

"My hunch is that women are more likely to smoke for weight control, especially in adolescence," said Sherry Pagoto, assistant professor in clinical psychology at the University of Massachusetts Medical School. "When people do quit smoking, one of the reasons they gain weight is that they increase their consumption of foods. They'll start snacking at the times they used to smoke."

Saarni SE, et al. Association of smoking in adolescence with abdominal obesity in adulthood: a follow-up study of five birth cohorts of Finnish twins. Am J Public Health 99(2), 2009.