Women may be more vulnerable to lung damage from smoking than men, according to new research.

In a study looking at chronic obstructive pulmonary disease (COPD), scientists at Brigham and Women’s Hospital, part of Harvard University Medical School, and the University of Bergen in Norway found that female smokers experienced reduced lung function at a lower level of exposure and at a younger age than male smokers.

“There’s an important public health message here,” says senior author Dr. Dawn DeMeo, assistant professor of medicine at Harvard. “Many women believe their smoking is too limited to be harmful, that a few cigarettes a day is a minimal risk. Our research shows there’s no safe amount, especially for women.”

The study, presented yesterday at the American Thoracic Society conference in San Diego, analyzed data from Norway of current and former smokers, 954 of whom had COPD; 955 were controls.

The gender differences were most pronounced among COPD patients under the age of 60, considered early onset, and those who smoked less than a pack a day for 20 years, the low-exposure group.

COPD is a progressive disease characterized by increasingly difficult breathing. It is most often caused by cigarette smoking and includes the conditions emphysema and chronic bronchitis
Another study, also reported this month, looked at 683 lung cancer patients at a Swiss treatment centre. It found that women tended to be younger when they got cancer even though, on average, they had smoked less than the men, suggesting an increased susceptibility.