The educational gap in tar and nicotine content in purchases of cigarettes: An observational study using large-scale...

The intensity of tobacco use is commonly measured by the number of cigarettes, which is inaccurate because it masks the heterogeneity and substances contained in tobacco. Unlike existing studies, this study adopted the tar and nicotine content of purchased cigarettes as proxies for smoking intensity and elicited socioeconomic disparities from the participants regarding tobacco use. Using a nationally representative consumer panel survey of Japan from 2010 to 2014, we found that socioeconomic disparities in smoking are more pronounced when tar and nicotine content in cigarettes is considered. University graduates purchased 26% fewer cigarettes, and 40% less tar or nicotine than their secondary school-educated counterparts. Low education groups purchased more tar-rich cigarettes, which cost less than low-tar cigarettes. The public health recommendations for reducing socioeconomic health inequalities might be understated because they are drawn from evidence based on the number of cigarettes smoked.