A Meta-Analysis of the Efficacy of Garden-Based Nutrition Education Programs

Obesity prevention programs seek to prevent or halt unhealthy weight gain by fostering healthy behaviors, such as increased consumption of fruits and vegetables.  Given the growing number of overweight and obesity in American youth, increased attention has been devoted towards practices and programs that support healthy behaviors in school-aged children.  Garden-based nutrition education programs are a type of intervention that has become especially popular in recent years.  Among the oft-purported benefits of garden-based nutrition education programs are that participation will result in increased knowledge of nutrition, increased preference for fruits and vegetables and/or increased fruit and vegetable consumption.  However, the number of studies that have examined these purported benefits are relatively few, and the sample size within each study is relatively small.  These limitations make it difficult to assess the efficacy of garden-based nutrition education programs, in terms of positive changes in knowledge, preferences and/or behavior, due to a lack of statistical power.  Meta-analysis is one way of increasing statistical power, by synthesizing the results of several independent studies that examine the same hypothesis.  We thus conducted a meta-analysis of published studies that compared garden-based nutrition education programs with a comparable control.  Many of the studies also included a more traditional nutrition education program in their study design.  Across all studies, children who participated in garden-based nutrition education programs increased preferences for and consumption of fruits and vegetables, relative to children in the control group.  In addition, children who participated in garden-based nutrition education programs exhibited greater preference for and consumption of fruits and vegetables, compared to children who participated in more traditional nutrition education programs.  However, children who participated in a more traditional nutrition education program exhibited a greater increase in nutrition knowledge, relative to children who participated in the garden-based nutrition education programs.  These results suggest that obesity prevention programs are more likely to foster postive behavior changes if they integrate garden-based lessons into nutrition education programs.