The evidence linking food environments to people’s body mass index (BMI) is inconclusive. While many studies do find associations between a person’s BMI and their proximity to fast-food restaurants and convenience stories, some studies find no associations.
This study examined the association between proximity to food establishment and BMI by linking longitudinal data from 1971 to 2001 for the Framingham Heart Study Offspring Cohort to food environment data. Information on food environment was gathered from several sources and limited to four principal towns: Framingham, Natick, Ashland and Holliston, Massachusetts. The sample included 3,113 subjects and 13,423 observations.
- Between 1971 and 2001, women’s mean BMI increased from 24.2 to 28.0; men’s increased from 26.7 to 28.9 over the same course of time.
- For women and men, the mean driving distance from their residence to the closest fast-food restaurant or nearest chain restaurant decreased.
- For every 1-kilometer increase in driving distance to the closest fast-food restaurant, BMI decreased by .11 units in the sample and .19 units among women.
This study showed a weak association between BMI and proximity to food establishment. Limitations included the lack of historical records for food environment and the study’s inability to follow subjects moving out of the area of study.