Smokeless tobacco: the epidemiology and politics of harm.

The health burden from tobacco smoking results almost entirely from inhalation of the components of smoke, although this is not widely known. The primary benefit of smoking is nicotine delivery, but nicotine can be obtained without combustion. Thus there is potential for tobacco harm reduction (THR), the substitution of lower-risk nicotine products for smoking. Epidemiological evidence suggests that smokeless tobacco causes about one one-hundredth the health risk of smoking. Despite the practice of harm reduction being widely accepted in public health, however, THR has faced fierce opposition from antitobacco activists. These activists have effectively misled the public about what aspect of smoking cigarettes causes the harm, convincing them that nicotine and tobacco themselves are harmful, ignoring the smoke. In the interests of promoting public health and rescuing science from politics, experts on inhalation hazards and health could play an important role in educating the public and policy makers about THR.