Salad bars and fruit and vegetable consumption

Fruit and vegetable consumption has been linked to the prevention of chronic diseases such as diabetes, some cancers, heart disease, and obesity. Many health organizations strongly advise people of all ages to eat at least five servings of fruit and vegetables every day. However, American children only eat an average of three and a half servings daily. School environment interventions combined with classroom curricula have shown the greatest promise for changing behaviors.

Because most children eat at least one meal at school per day, the school cafeteria remains an important setting for exploring connections between the environment and student's dietary habits. Salad bars have become a recommended method to increase fruit and vegetable consumption without strong evidence of their effectiveness. Therefore, a recent study in JADA used plate waste weighing to determine if elementary school students with self-service salad bars consume more fruits and vegetables compared with students served proportioned amounts determined by cafeteria staff.

Two-hundred ninety-four students in first grade through fifth grade were randomly selected from two schools with salad bars and two with proportioned servings. Fruits and vegetables were measured to the nearest gram after students selected their fruit and vegetable items but before the entree items. Consumption was calculated by subtracting the fruit and vegetable postconsumption weight from preconsumption weight.

Students who attended schools with salad bars present took 112 70 g fruits and vegetables compared with 104 86 g taken by students at nonsalad bar schools. These differences were not statistically significant. Fruit and vegetable consumption was positively related to the number of fruit and vegetable items offered at salad bars. The number of items offered varied by the schools with the two salad bars schools offering four and seven items each and the preportioned schools offering five items each.

The results do not support the hypothesis that salad bars increase fruit and vegetable consumption among elementary school students. Since fruit and vegetable variety of salad bars was associated with greater consumption, the findings provide some suggestions about the mechanisms by which variety could increase consumption. Some limitations of this study include the small number of schools studied and that each school was sampled on one day only. Further studies should include other potential environmental mediators of salad bar effectiveness, such as location, presentation, and interaction with entrees.