Incentives, time use and BMI: The roles of eating, grazing and goods

In the 2006–2007 American Time Use Survey and its Eating and Health Module over half of adults report grazing (secondary eating/drinking) on a typical day, with grazing time almost equaling primary eating/drinking time. An economic model predicts that higher wage rates (price of time) will lead to substitution of grazing for primary eating/drinking, especially by raising the number of grazing intervals relative to meals. This prediction is confirmed in these data. Eating meals more frequently is associated with lower BMI and better self-reported health, as is grazing more frequently. Food purchases are positively related to time spent eating—substitution of goods for time is difficult—but are lower when eating time is spread over more meals.