Nicotine is definitely addictive, but scientists have been debating for several decades the effect of menthol in hooking people on tobacco. Some researchers suspect that menthol allows smokers to take deeper drags or puffs on cigarettes, drawing in greater amounts of nicotine and its byproducts.
"It helps the poison go down smoother," says Jonathan Foulds, the director of the Tobacco Dependence Program at the University of Dentistry and Medicine of New Jersey's School of Public Health.
In a cessation program at his university, Foulds found that people who smoked menthol cigarettes seemed to have more difficulty quitting than those who smoked regular cigarettes.
Nearly 1,700 people were enrolled in the program. They signed up, Foulds says, because they wanted help quitting. Millions of Americans say they've tried to quit smoking, and some groups appear to have a harder time than others, such as low-income, less-educated African-Americans and Hispanics.
The current cost of smoking, particularly in the northeastern United States, would certainly be enough to make a poor person want to break the habit. In New Jersey, a pack of cigarettes costs $8; in Manhattan, a pack costs $11.
For many, those prices mean it's time to quit or cut back. But Foulds says it's not quite that simple when the body is addicted to a certain level of nicotine.
Over time, he says, "Your body tries to inhale more smoke per cigarette to get the usual dose of nicotine. With regular cigarettes, it becomes harsh because nicotine and the toxins in the smoke are harsh on your throat."
Menthol smokers, it appears, don't have the same problem. Those who smoke menthols say it creates a cooling, soothing sensation.
Menthol is a cooling agent, Foulds says, and that makes it easier to inhale more smoke per cigarette and perhaps get more nicotine.
Dr. Kolawole Okuyemi of the University of Minnesota has studied disparities in black and white smokers, and the effect of menthol cigarettes on biochemical markers.
A study in the Journal of the American Medical Association found that African-Americans who smoke menthol cigarettes inhale a higher volume of carbon monoxide compared to those who smoke non-menthol cigarettes, according to Okuyemi. They also take in more byproducts of nicotine that can be measured in the blood or the saliva.
"If you take a menthol smoker who smokes 10 cigarettes and a non-menthol smoker who smokes 10 cigarettes a day, the carbon monoxide, the nicotine and cotinine [a byproduct of nicotine] will be higher for the menthol smoker." That suggests "there is something about menthol that makes it easier to smoke more intensely," Okuyemi says.
One of the biggest indicators of a person's addiction is how soon they light up after they get up in the morning, Okuyemi says. Studies show that menthol smokers light up sooner than regular smokers – as soon as five minutes after they get out of bed.
Among African-Americans who smoke, the vast majority smoke mentholated cigarettes, and many of these studies compared biochemical markers in black and white smokers. It may have more to do with the fact that African-Americans metabolize nicotine more slowly, says Okuyemi. That would mean that they are more likely to retain nicotine.
Andrew Hyland of the Roswell Park Cancer Institute isn't entirely convinced that menthol aids addiction. Though not linked in any way to Lorillard, which manufactures menthol cigarettes, Hyland's study was cited by one of the company's representatives as evidence that menthol cigarettes are no more addictive than others.
Hyland followed 13,000 smokers for five years. He found that low-income and less-educated people had a harder time quitting, but he found no difference between whites and blacks, or menthol and regular cigarette smokers. He agrees that menthol's role in smoking is not entirely neutral.
"If you look at how deeply people inhale or the puff volumes — how much smoke they bring into their lungs — some studies show that it is easier [to smoke menthol], but other studies show it's not," says Hyland. "To me, that means it is probably not a huge deal, especially relative to the thing that gets people hooked. The menthol is a tool, a marketing tool. Once they are hooked on the product, with the nicotine, that's when they're in trouble."
Historical documents show that the industry did in fact target African-Americans in the late 1950s. At that time, African-Americans were no more likely to smoke menthol than white Americans. Lorillard maintains that a fourth of white Americans who smoke today smoke menthol cigarettes. About 75 percent of African-American smokers use menthol cigarettes now, according to the Centers for Disease Control and Prevention.
They start later in life and quit later, like 56-year-old Larry Harrison, who gave up cigarettes after 38 years.
"Fourteen days clean," he says. For those who don't think that sounds like a very long time, he says, "When you've been smoking 38 years, one day is a long time without a cigarette."