This paper analyzes the role of prices in determining food purchases and nutrition using a detailed transaction-level observation for a large, nationally-representative sample of U.S. consumers over the years 2002-2007. Using structural demand estimates, researchers simulated the effect of a 20 percent product tax on soda, other sugar-sweetened beverages, packaged meals, and snacks, and 20 percent nutrient taxes on fat, salt, and sugar. They found that overall nutrient-specific taxes had much larger effects on nutrition than the product-specific taxes. Nutrient-specific taxes did not cost more in terms of consumer utility. While a 20 percent soda tax reduced sugar purchases by 10.35 percent, it only reduced overall caloric intake by 4.84 percent. Taxing packaged meals slightly increased overall caloric intake, and taxing snacks/candy had modest impacts on food purchased and nutrition. In contrast, taxing nutrients had large impacts on nutrition without producing larger welfare losses than product-specific taxes. Among the three nutrient-specific taxes examined, sugar taxes were the most effective. A 20 percent nutrient tax on sugar reduced sugar consumption by 16.41 percent, while also reducing caloric intake by 18.54 percent and salt consumption by 9.63 percent.  These findings suggest that nutrient-specific taxes could have an effect in inducing healthier purchasing behavior among consumers.