For decades now, cigarette makers have marketed so-called light cigarettes - which contain less nicotine than regular smokes - with the implication that they are less harmful to smokers' health. A new UCLA study shows, however, that they deliver nearly as much nicotine to the brain. Reporting in the current online edition of the International Journal of Neuropsychopharmacology, UCLA psychiatry professor Dr. Arthur L. Brody and colleagues found that low-nicotine cigarettes act similarly to regular cigarettes, occupying a significant percentage of the brain's nicotine receptors. Light cigarettes have nicotine levels of 0.6 to 1 milligrams, while regular cigarettes contain between 1.2 and 1.4 milligrams
The researchers also looked at de-nicotinized cigarettes, which contain only a trace amount of nicotine (0.05 milligrams) and are currently being tested as an adjunct to standard smoking-cessation treatments. They found that even that low a nicotine level is enough to occupy a sizeable percentage of receptors. The two take-home messages are that very little nicotine is needed to occupy a substantial portion of brain nicotine receptors, Brody said, and cigarettes with less nicotine than regular cigarettes, such as 'light' cigarettes, still occupy most brain nicotine receptors. Thus, low-nicotine cigarettes function almost the same as regular cigarettes in terms of brain nicotine-receptor occupancy.
In addition to Brody, other authors of the study were Mark A. Mandelkern, Matthew R. Costello, Anna L. Abrams, David Scheibal, Judah Farahi, Edythe D. London, Richard E. Olmstead, Jed E. Rose and Alexey G. Mukhin. The researchers report no conflicts of interest. Rose, from the Duke University School of Medicine, has received research support for a study unrelated to the present paper from Vector Tobacco Inc., the manufacturer of Quest cigarettes. The research was supported by the National Institute on Drug Abuse, the Veterans Administration, the Tobacco-Related Disease Research Program, the National Alliance for Research on Schizophrenia and Depression, and the Office of National Drug Control Policy.