Previous studies have shown that cigarette smoking is associated with higher rates and severity of food insecurity but do not address how population-level smoking rates change in response to changes in food security. Trend analysis of serial cross-sectional data. Data from a representative survey of US households. Adults within households participating in both the Food Security Supplement and Tobacco Use Supplement of the Current Population Survey during 5 overlapping administrations from 1998 to 2011. A "current smoker" is defined as someone who indicated that they currently smoke on "some days" or "every day." A household's food security is coded as "secure" or "insecure," according to responses to a food security scale, interpreted using a US Department of Agriculture standard. Descriptive comparison of the roughly triennial trends in the prevalence of food insecurity and current smoking from 1998 to 2011. The prevalence of food insecurity increased by 30% among adults overall versus 54% among current smokers, with most of the changes occurring following the economic recession of 2008 and 2009. Over this same period, the prevalence of current smoking declined by 33% among food-secure adults and only 14% among food-insecure adults. Food insecurity increased more markedly among adult smokers than nonsmokers, and the prevalence of smoking declined more slowly in food-insecure households, indicating that more low-income smokers are facing hunger, which may at least partly be due to buying cigarettes.