Self-control, which is also referred to as future-orientation or time preference, has been of longstanding interest to economists and psychologists as an important predictor of health behaviors. Many preventive health behaviors, including obesity prevention, involve immediate costs (healthy eating and exercise) and delayed benefits (lower risk of chronic disease). Time preference measures the extent to which individuals value future outcomes relative to immediate ones. Therefore, individuals with future-oriented time preferences, or more self-control, should be more likely to adopt preventive health behaviors. Among adults, time preferences have been linked with health, smoking, drinking and drug abuse behaviors (Bradford et al., 2014; Chabris et al., 2008; Harrison et al., 2004; Khwaja et al., 2006; Kirby and Petry, Weller et al., 2008), and demand for medical screening tests or vaccines (Picone et al., 2004; Chapman and Coups, 1999). Among children and adolescents, a higher level of impatience has been linked to greater expenditures on alcohol and cigarettes (Sutter et al., 2013), a greater number of disciplinary referrals at school (Castillo et al., 2011), lower high school completion rates (Castillo et al., 2015), and a range of adverse lifetime outcomes related to school performance, health, labor supply, and income (Golsteyn et al., 2014). However, only limited evidence exists about how self-control relates to BMI in children and adolescents (Seeyave et al., 2009; Sutter et al 2013). Moreover, these studies do not examine the link between self-control and diet and physical activity behaviors.
In this paper, we use panel data from the Early Childhood Longitudinal Study- Kindergarten Class 1998 (ECLS-K) to examine the relationship between self-control and children’s diet and activity behaviors and BMI outcomes. This is the only longitudinal dataset in the U.S. that is nationally representative and has measurements of children’s BMI in each wave along with measures of self-control from multiple sources (i.e. teachers, parents, self). Preliminary results suggest that children with higher self-control have significantly lower BMI and are significantly less likely to be obese, in both cross-sectional as well as longitudinal models. Moreover, we also find an expected link with dietary behaviors, including lower consumption of fast food and sugar-sweetened beverages, and lower likelihood of purchasing junk foods at school.
