Study Shows Genetics Could Make You More Vulnerable to Nicotine Addiction

Do you remember the first time you tried nicotine? When you smoked your first cigarette, did you enjoy it or were you immediately turned off? A new study from John Hopkins University School of Medicine investigated why people have such different reactions to their first nicotine exposures and the results might surprise you. It turns out that your DNA could be largely responsible for whether or not you will become addicted.

Researchers recruited 18 participants to investigate why some people are more likely than others to be addicted to nicotine. When participants were given nicotine, they had very mixed reactions. Half of the group enjoyed the effects and tended towards repeated use while the other half wanted to avoid it completely after experiencing negative symptoms.

“From an addiction point of view, nicotine is a very unusual drug,” said Professor Roland Griffiths. “When you give people nicotine for the first time, most people don’t like it. It’s different from many other addictive drugs, for which most people say they enjoy the first experience and would try it again.”

All of the participants were non-smokers with no prior history of nicotine use. The researchers doled out pills, labeled as A and B. One pill contained nicotine and the other was a placebo. Each participant received two pills per day, taken at least two hours apart. The pills containing nicotine had a very small dosage, estimated to be ten times lower than the nicotine in a cigarette. The researchers wanted to provide just enough of the chemical for participants to feel some kind of effect.

The study’s participants didn’t know what was in the pills, but they were told it could be a number of substances like chamomile, sugar, theobromine, ginseng, kava, or nicotine. Each day, the participants would take their two pills, but the order was regularly mixed up. After 10 consecutive days, participants were questioned to see if they could tell the difference between pill A and pill B. If they couldn’t tell any difference, the nicotine dosage was increased. Once the participants could identify the differences between the pills, they were allowed to choose whether they wanted to receive pill A or pill B at each dosage.

Exactly half of participants opted to take the nicotine pill and reported positive effects like improved mood, a better ability to concentrate and focus, or more energy. The other half preferred the placebo pill and they said the nicotine pill left them feeling light-headed, dizzy, or sick. In a strange twist, some participants actually thought the placebo pill contained a drug that made them drowsy.

The study showed that people have very different reactions to nicotine during their initial exposure. Some naturally gravitate towards it while others find it to be unpleasant and avoid future encounters. Griffith said the diverse reactions stem from differences in genetics and metabolisms. The people who enjoyed nicotine and even sought it out for the positive effects would be more likely to end up addicted than those who were naturally turned off after their first exposure.

Griffith believes this discovery could open up a whole new world of opportunities for continued study to better learn how to help people who struggle with nicotine addiction. “I hope our findings will point the way toward future interventions that prevent or treat nicotine addiction, a topic of increasing importance in light of the expanding marketing of electronic nicotine delivery devices – e-cigarettes – to youthful nicotine non-users.”

When you think about your first exposure to nicotine, do you remember how you reacted? Did you enjoy it at first? How soon after your first exposure did you find yourself struggling with addiction?