Our observation that harm escalation ( I.e., from smoking or smoking to dual use ).was more likely among men than among women is not unexpected. This observation is consistent with the low prevalence of overall smokeless tobacco use among women, which is likely related to cultural norms in the United States pertaining to smokeless tobacco use. Even in Sweden, where smokeless tobacco use is prevalent ( 20% of adult male use smokeless tobacco ) and holds unique historical and cultural significance , the prevalence of smokeless tobacco use among women is low. In a study assessing tobacco quitting or switching in the TUS-CPS , smokeless tobacco use among women was low and no women demonstrated harm reduction. Our findings and those of other investigators suggest that a harm reduction strategy using smokeless tobacco would have little or no impact on women in the United States.