Grains have historically represented a major component of human diets and were predominantly consumed in whole form until the first half of the 19th century, when a combination of technological innovations and market dynamics made refined grains, hitherto a premium product, affordable and available to the masses. Grains still account for more than half of the total caloric intake among vulnerable populations worldwide, and their dominant consumption in refined form turns a nutrient-dense, protective food into a nutrient-poor one contributing to growing rates of obesity and noncommunicable disease. Shifting a substantial portion of global grain consumption to whole grains is potentially one of the most significant and achievable improvements to diets and food systems worldwide. In countries with significant micronutrient deficiencies, a switch from refined to fortified whole grain foods can enable institutional channels such as school feeding programs to measurably improve diet quality in a budget-neutral way.