Correspondence
Regulation of the Nicotine Content of Cigarettes
N Engl J Med 1994; 331:1530-1532December 1, 1994
- Article
To the Editor:
Benowitz and Henningfield (July 14 issue)1 have calculated a recommended threshold level of nicotine in cigarettes below which they believe nicotine dependence is less likely to occur. I have questions about the assumptions behind and the possible implications of this calculation as well as the methods used to calculate this level.
One assumption behind this calculation is that cigarettes with lower levels of nicotine would decrease the progression of smoking from experimentation to nicotine dependence. Empirical studies have both supported and contradicted this assumption.2 In fact, some results have suggested low-nicotine cigarettes may be more likely to induce regular smoking because they are less harsh.3 In addition, Dr. Henningfield and others have criticized low-nicotine smokeless tobacco as a “starter product.” A related assumption is that once people have begun to smoke regularly, lower-nicotine cigarettes might deter the development of more severe nicotine dependence. However, in a recent editorial about labeling in cigarettes, Dr. Henningfield and his colleagues stated that “cigarette smokers obtain an average of 1 mg of nicotine from each cigarette they smoke, whether the nicotine yield is 0.1 mg or 2 mg.”4 If this is true, it is difficult to understand how changes in the nicotine level would affect the development of nicotine dependence.
The authors' calculation of a nicotine threshold is based on the observation that persons who smoke five or fewer cigarettes per day (“chippers”) are unlikely to be nicotine-dependent.5 The implicit assumption is that by smoking so few cigarettes, chippers have prevented nicotine dependence. However, one must remember chippers were not randomly assigned to this low rate of smoking, but rather selected it themselves. Thus, I think it more likely that smoking a few cigarettes per day is a consequence of resistance to nicotine dependence -- that is, chippers differ from other smokers a priori. In fact, chippers are the offspring of parents who are less likely to begin smoking or, if they did, are more likely to have quit.5
One unintended consequence of a recommended threshold might be that cigarettes with nicotine levels below this cutoff point would be perceived by adolescents to be “safe” in terms of leading to nicotine dependence. Whether smokers of low-nicotine cigarettes are less dependent on nicotine than smokers of cigarettes with moderate or high levels of nicotine has not been well studied. Recalculations from our recent study of persons who quit smoking on their own6 showed that of the 84 such persons who smoked cigarettes containing less than 0.5 mg of nicotine, only 35 percent were able to stop smoking for one week and only 8 percent were able to stop for six months; of those who did quit for one week, 55 percent fulfilled criteria for nicotine withdrawal outlined in the Diagnostic and Statistical Manual of Mental Disorders (third edition, revised). In fact, persons who smoked cigarettes containing less than 5 mg of nicotine did not have better success rates than those who smoked cigarettes containing more than 5 mg of nicotine, nor were they less likely to have symptoms of withdrawal.
6 ReferencesJohn R. Hughes, M.D.
University of Vermont, Burlington, VT 05401-14191
Benowitz NL ,Henningfield JE . Establishing a nicotine threshold for addiction -- the implications for tobacco regulation. N Engl J Med 1994;331:123-125
Full Text | Web of Science | Medline2
Pomerleau OF ,Collins AC ,Shiffman S ,Pomerleau CS . Why some people smoke and others do not: new perspectives. J Consult Clin Psychol 1993;61:723-731
CrossRef | Web of Science | Medline3
Silverstein B ,Kelly E ,Swan J ,Kozlowski LT . Physiological predisposition toward becoming a cigarette smoker: experimental evidence for a sex difference. Addict Behav 1982;7:83-86
CrossRef | Web of Science | Medline4
Henningfield JE ,Kozlowski LT ,Benowitz NL . A proposal to develop meaningful labeling for cigarettes. JAMA 1994;272:312-314
CrossRef | Web of Science | Medline5
Shiffman S . Tobacco “chippers” -- individual differences in tobacco dependence. Psychopharmacology (Berl) 1989;97:539-547
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Hughes JR ,Gulliver SB ,Fenwick JW , et al. Smoking cessation among self-quitters. Health Psychol 1992;11:331-334
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To the Editor:
The tobacco industry has successfully adapted to every regulatory strategy designed to reduce the demand for cigarettes, and there is little reason to believe that it could not also meet the nicotine challenge. From the late 1920s (when one of the earliest articles reporting a relation between smoking and lung cancer was published in the Journal1) to the mid-1960s (when the first report on smoking by the Surgeon General appeared), cigarette advertising in both the lay and medical press featured health claims designed to allay anxiety about smoking.2 The creation of various cigarette filters in the 1950s was a direct response to public concern about lung cancer spawned by the publication of the first major epidemiologic studies on smoking and disease. Low-tar cigarettes emerged in the 1960s in reaction to renewed questions by the Surgeon General. Light and ultra-light brands were introduced during the fitness craze of the 1970s.
In particular, the hoped-for reduction in deaths from lung cancer as a direct consequence of a reduction in tar levels has proved illusory. Such a strategy has enabled the tobacco industry to become, in effect, our leading health educator, as increasing numbers of consumers have switched to lower-tar brands -- rather than stopping smoking -- in the misguided belief that they can smoke more safely. The introduction of ultra-low-nicotine cigarettes may facilitate the initiation of smoking among children.
Efforts to regulate tobacco products will be of little consequence without advertising campaigns designed to weaken the faith of consumers in the product, its promotion, and its promoters. Researchers and clinicians alike must place increased emphasis on changing the public's attitudes about smoking, cigarette advertising, and the tobacco industry.
2 ReferencesAlan Blum, M.D.
Baylor College of Medicine, Houston, TX 77030-34981
Lombard HL ,Doering CR . Cancer studies in Massachusetts. 2. Habits, characteristics and environment of individuals with and without cancer. N Engl J Med 1928;198:481-487
Full Text | Web of Science2
Blum A . When “more doctors smoked Camels”: cigarette advertising in the Journal. N Y State J Med 1983;83:1347-1352
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Author/Editor Response
The authors reply:
To the Editor: Drs. Hughes and Blum are concerned that the introduction of ultra-low-yield cigarettes might facilitate the initiation of smoking among children, particularly if the cigarettes are perceived to be “safe.” Furthermore, Dr. Hughes points out that cigarette smokers can get plenty of nicotine from currently marketed low-yield cigarettes. Let us reemphasize that the cigarettes we propose would have a low nicotine content and therefore differ greatly from currently marketed cigarettes with a low nicotine yield. It would be impossible to obtain 1 mg of nicotine from the proposed cigarette, since the entire cigarette would contain only 0.5 mg of nicotine. We have discussed these issues and a new cigarette-labeling proposal in detail elsewhere.1
Whether these low-nicotine cigarettes would be more or less acceptable to novices as starter cigarettes is unknown. The main predictors of the initiation of smoking are peer influences and other personal and environmental factors. Very few children choose to smoke the low-yield cigarettes that are available despite the presumption that these are milder than the higher-yield cigarettes. The thrust of our proposal is not to prevent experimentation, which is likely to occur no matter what type of cigarettes are available, but rather to prevent the progression of smoking for nonpharmacologic reasons to smoking for pharmacologic (i.e., addictive) reasons.
As pointed out by Dr. Blum, a program to reduce tobacco use must include a variety of interventions in addition to nicotine regulation, including increased taxation, educational programs, counteradvertising, and restriction of access to tobacco among young people. We agree that a strategy to reduce the nicotine in cigarettes gradually should be considered as one component of a broad-based effort to discourage any tobacco consumption and to encourage cessation efforts. Such a strategy must make it clear that the proposed low-nicotine cigarette is not safe. Combustion of tobacco, regardless of how much nicotine it contains, will generate carcinogenic chemicals, oxidant gases, and other hazardous chemicals. There will have to be clear labeling stating that smoking low-nicotine cigarettes is as hazardous to health as smoking higher-yield cigarettes.
Dr. Hughes has pointed out that a cigarette associated with a lower likelihood of addiction might be perceived as safer. The example he gives of dependence on currently marketed low-yield cigarettes is not relevant, however, because he fails to differentiate between low nicotine content and low nicotine yield, as discussed previously. The proposed low-nicotine cigarette should be less addictive, so that when people do decide to quit it will be much easier to do so, but it must be made clear that smoking even these cigarettes is unsafe.
Finally, Dr. Hughes questions our use of data from chippers to estimate a threshold of nicotine intake associated with addiction. We agree that chippers are self-selected, and we do not know whether a person who would otherwise have become addicted to high-nicotine cigarettes would become addicted to low-nicotine cigarettes if they were the only ones available. There is some pharmacologic support for the proposition that a daily intake of 5 mg of nicotine might be generally nonaddictive, since with such an intake the levels of nicotine in the body would be extremely low for much of the day, thus reducing the effects on nicotinic receptors, as compared with those produced by higher intakes. There is no way of empirically testing the proposition that nonsmokers would be less likely to become addicted to low-nicotine cigarettes as we define them. We recommend that any trial of nicotine reduction be accompanied by careful observation of smoking behavior and nicotine intake so that regulation strategies could be modified if the desired objectives were not being met.
1 ReferencesNeal L. Benowitz, M.D.
University of California, San Francisco, San Francisco, CA 94110Jack Henningfield, Ph.D.
National Institute on Drug Abuse, Baltimore, MD 212241
Henningfield JE ,Kozlowski LT ,Benowitz NL . A proposal to develop meaningful labeling for cigarettes. JAMA 1994;272:312-314
CrossRef | Web of Science | Medline
