AUSTIN, Texas — “Very light” smoking, defined as five or fewer cigarettes per day, is common among young adult women in the United States, according to researchers at The University of Texas at Austin.

The 2011 National Survey on Drug Use and Health in the United States revealed that while overall prevalence and cigarette consumption have declined during the past two decades, nearly 1 in 5 women between the ages of 18 and 25 are very light smokers.

“Smoking, even at low levels and intermittently, carries significant health risks, such as cardiovascular and pulmonary diseases and an increased risk of lung cancer,” said Carole K. Holahan, a professor in the Department of Kinesiology and Health Education and associate faculty in the Center for Women’s and Gender Studies.

Using survey data from 9,789 women in emerging adulthood (aged 18 to 25), C.K. Holahan, graduate researcher Xioyin Li and psychologist Charles Holahan compared social and psychological features of very light smokers with those of women at other smoking levels.

Very light smokers made up more than 60 percent of the young female smokers surveyed. And when researchers considered characteristics separately, very light smokers were more likely than other smokers to be younger (18 to 20), single, from a minority group and have some college education.

“Risky behavior is common in young adults; however, emerging adulthood is an important developmental stage, particularly for women’s reproductive health,” said C.K. Holahan. “Cigarette use before or during pregnancy poses threats to maternal and child health.”

As with light and heavier smokers, very light smokers were more likely than nonsmokers to report past-month psychological distress and substance use, as well as lifetime depression. Very light smoking was also associated with higher risk of binge drinking.

Compared with heavier smokers, very light smokers recognized the risks of smoking and were less likely to report signs of nicotine dependence or smoke daily.

“There may be several pathways to very light smoking among women in emerging adulthood, such as the cost of cigarettes, weekend partying in college, emotional distress and multiple substance use,” said Li, a health behavior and health education graduate student.

Knowing the prevalence of very light smoking in our society will help health care providers and educators screen and prevent tobacco use, C.K. Holahan said.

“The profile of very light smokers looked more promising for smoking cessation interventions than that of other smokers,” she said. “Smoking intervention programs and policies directed at emerging-adult women need to be based on an understanding of the diverse characteristics of this population.”

The study “Sociodemographic and psychological characteristics of very light smoking among women in emerging adulthood, national survey of drug use and health, 2011” appeared in the journal Preventing Chronic Disease on July 16.