August 2009

IZA DP No. 4378: Grazing, Goods and Girth: Determinants and Effects

published as "Incentives, time use and BMI: The roles of eating, grazing and goods" in: Economics and Human Biology, 2010, 8 (1), 2-15

Using the 2006-07 American Time Use Survey and its Eating and Health Module, I show that over half of adult Americans 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 incidents 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.