Quantifying the association between obesity, automobile travel, and caloric intake

Objective: The objective of this study is to assess the association between average adult body mass index (BMI), automobile travel, and caloric intake in the US in order to predict future trends of adult obesity.

Methods: Annual BMI data (1984-2010) from the Behavioral Risk Factor Surveillance System (BRFSS), vehicle miles traveled data (1970-2009) from the Federal Highway Administration, licensed drivers data (1970-2009) from the Federal Highway Administration, and adult average daily caloric intake data (1970-2009) from the US Department of Agriculture were collected. A statistical model is proposed to capture multicollinearity across the independent variables.

Results: The proposed statistical model provides an estimate of changes in the average adult BMI associated with changes in automobile travel and caloric intake. According to this model, reducing daily automobile travel by one mile per driver would be associated with a 0.21 kg/m(2) reduction in the national average BMI after six years. Reducing daily caloric intake by 100 calories per person would be associated with a 0.16 kg/m(2) reduction in the national average BMI after three years.

Conclusion: Making small changes in travel or diet choices may lead to comparable obesity interventions, implying that travel-based interventions may be as effective as dietary interventions.