An Unintended Consequence of Complete Flavor Bans: More Youth Smoking Review of: Abigail S. Friedman, “A Difference-in-Differences Analysis of Youth Smoking and a Ban on Sales of Flavored Tobacco Products in San Francisco, California,” Reviewed by: Chelsea Boyd In response to continued concern over youth vaping rates, some jurisdictions have implemented flavor bans in an attempt to make nicotine products—combustible cigarettes, vaporizers (vapes), e-cigarettes and other electronic nicotine delivery systems—less appealing to young people. The ban in one jurisdiction, San Francisco, enabled researchers [2]to evaluate what happens to youth smoking rates following a ban on flavored tobacco products.