Cigarettes, drugs and alcohol pose different addiction risks for women, according to a study released last week by the National Center on Addiction and Substance Abuse. The study is among the first to thoroughly consider how women interact with addictive substances.

The study identified the times girls are most likely to get addicted, including transitions from middle school to high school and from high school to college. Women who move around a lot, have eating disorders, have been physically abused or are addicted to caffeine are at a higher risk of addiction to drugs or alcohol.

The study also said women are more likely to suffer stronger health consequences than men from the same amount of drinking, smoking or drug use. However, although the overall number of teenagers who smoke, drink and use drugs is decreasing, one in four women smoke, one in two drink, and one in five use marijuana. The number of women using these substances is now roughly equal to those of men, and women now start to use around the same age as men do.

Reasons for starting to smoke also tend to be different for women and men, the study said. Women tend to start in a private environment to relieve stress, whereas boys tend to start in a more social environment.

Differences like these should lead to gender-specific treatment groups, which would be more effective than coed groups, according to the report.

Douglas Jorenby, the director of clinical services at the Center for Tobacco Research and Intervention, said he hasn’t noticed a difference between men and women in how quickly they get addicted to cigarettes, but he said that women have a harder time quitting and staying quit then men do.

“Many women [who are trying to quit] say they feel like they’ve lost their best friend,” Jorenby said. He also said the CTR tries to provide a “new non-lethal best friend in the form of support groups.”

“The groups are open to men and women equally, but over time there is usually around a two-thirds majority of women,” Jorenby said. He speculated that this could illustrate an increased need that women have for personal support, but it could also mean more women are seeking help than men.

Traditional methods for quitting may not be as effective for women either, said Jorenby; there is evidence that women don’t benefit as much as men from the nicotine patch.

The first few times someone smokes, they often feel dizzy or nauseous, but with practice these negative effects are minimized, and positive ones — such as relaxation and alertness — are maximized, said Jorenby.

“It’s easy to become addicted to tobacco,” Jorneby said. “An average of three cigarettes are all that is needed to become a regular smoker.”

Some reasons that people start smoking, such as losing weight, may have some truth to them; on average, smokers weigh less than non-smokers do.

Jorenby said other reasons, like the relaxation factor, have more complex explanations. In a scientific test, two subjects were monitored in a stressful situation. One subject had just smoked a cigarette. Both subjects had the same stressed-out body state, but the smoker reported feeling much more relaxed.

“Physiologically, smoking doesn’t appear to be relaxing,” Jorenby said. “But perhaps smokers have become used to the ‘stressed’ feeling.”

Eventually the body’s nervous system changes to develop a dependence on nicotine. However, the actual process of how those changes occur remains a mystery.

Charles Landry, a professor of psychiatry at the University of Wisconsin, is trying to discover the genes responsible for causing cravings.

“People can suffer from cravings even 10 years after they quit smoking,” Landry said.

Landry uses animal models to try to identify the changes in genes responsible for addition and relapse.

“Adolescents seem to become addicted after using fewer cigarettes than adults do,” Landry said. “There is some evidence that nicotine addiction may predispose you to sensitivity to other drugs.”

Landry said research in the area is exploratory at this point.

“The field as a whole is trying to get a handle on the biochemical components that are responsible for addiction,” Landry said. “Understanding the chemistry could lead to more effective treatments in the future.”