Theses Doctoral

From Root to Fruit: The Development and Evaluation of the In Defense of Food Curriculum. A Nutrition Education Afterschool Curriculum for Middle School-aged Children.

Bhana, Hiershenee

Over the last few decades, a shift in the American diet towards more ready-to-eat, ready-to-heat foods and fewer fruits and vegetables has occurred. Simultaneously, there has also been a rise in chronic diet-related diseases disproportionately affecting underserved and minority populations. Highly processed foods are cheap and abundant, they tend to be nutritionally poor, and are disproportionately marketed to minority youth. Despite an increased public focus on health and many health promotion initiatives, health disparities continue to widen.
Michael Pollan and many others criticize the nutrition and food industries for focusing health messages on composite nutrients and bioactive components in foods (for example eat less fat or eat more fiber) rather than on dietary patterns (eat fewer highly processed, eat more whole foods). Pollan’s book, In Defense of Food (IDOF), was made into a documentary film, highlighting these important messages and generating solutions for what to eat to be healthy.
This study is a development project that describes the systematic development and evaluation of the In Defense of Food nutrition education curriculum as the companion guide to the documentary film. It was designed for a middle-school aged audience in an afterschool setting to encourage an increased intake of fruits and vegetables and a decreased intake of highly processed foods.
In the formative stages, a project development assessment was conducted to inform the development of the curriculum for its target audience and setting. Often health promotion programs focus on ensuring the valid development of content. This study examined delivery and logistical considerations specific and important to the afterschool context. Delivery, refers to how the content is executed. Findings suggest that a curriculum with youth in an afterschool setting should include non-didactic instruction, the sharing of teacher perspectives to elicit student perspectives, address different learning needs, and help students learn through an incremental process. Logistics included the time, space, and financial constraints of the afterschool settings. Findings indicate that teachers generally only have 1-2 hours of preparation time, a lack of fixed classroom space, and small financial budgets for accompanying lesson resources and materials.
Next, the study developed the content of the IDOF curriculum using a systematic stepwise behaviorally-focused and theory-based process, the Nutrition Education DESIGN procedure. The DESIGN procedure was applied to try and enhance motivation and facilitate the achievement of the actionable behavioral outcomes of the curriculum: an increased intake of fruits and vegetables and a decreased intake of highly processed foods. The behavior-change theories applied were the Social Cognitive Theory and The Self Determination Theory. The resulting curriculum consisted of 10 sessions, 2 hours each, based on IDOF’s basic message of “Eat Food; Not Too Much, and Mostly Plants.” The curriculum was activity-based, used clips from the documentary film in each session with accompanying discussions, incorporating opportunities to taste and prepare foods, and to think critically about food marketing.
The curriculum was piloted in 3 classes in 2 afterschool programs in New York City with a total of 32 youth. Professional development training was provided to the three teachers facilitating the curriculum before the start of the program and on-going as needed throughout.
A mixed methods process evaluation was conducted to examine aspects of the curriculum that were more and less likely to be delivered and variations in how they were received by students. Trained research staff conducted in-class observations in nine of the 10 lessons measuring components of program delivery (fidelity, percentage completion, teacher attitude/motivation, classroom management) and program reception (student engagement). Trained staff administered student satisfaction surveys at the end of each lesson. Descriptive statistics and intra-class correlations were calculated. Observation field notes were codified using inductive content analysis. A high proportion of the curriculum was completed across all three classrooms, however the majority of fidelity deviations occurred for those involving worksheets, performance activities, and homework assignments. Social modeling in support of behaviors and greater teacher motivation to engage with the materials was seen in high performing lessons whereas modeling that undermined the curricular messages and low motivation were observed in low performing lessons. This study revealed that for this context, activities that require students to work alone at their desks on worksheets, that require them to perform in front of their peers and return materials to subsequent lessons should be minimized. Additionally professional development to increase teacher buy-in may be important to improve delivery of the curriculum.
Lastly, a mixed methods outcome evaluation was conducted using pre-posttest surveys measuring the targeted dietary intake of the target behaviors and psychosocial determinants (n=32), one-on-one assessments of knowledge using a quantitative rubric and accompanying notes (n=22), and semi-structured in-depth interviews (n=12). A statistically significant increase in intake of fruits and vegetables from pre to posttest, and trends towards decreases in highly processed foods were seen. Significant changes in the psychosocial determinants: self-efficacy and positive outcomes expectations were also seen; all other changes were not significant but generally in the desired direction. One-on-one knowledge assessments demonstrated that short actionable rules were easily recalled and understood. Findings also suggest that youth adopted self-regulation skills and elicited support from their family members to help them increase their intake of fruits and vegetables. However social and environmental barriers were described as difficult to overcome for highly processed foods.
Decreasing the health disparity gap starts with ensuring that nutrition education programs are developed to be responsive to the specific needs of the target audience and setting. While Pollan’s messages have been successful in raising awareness about the American diet for the general public, this study showed that they can also be integrated into educational materials that, when systematically designed and well implemented, can increase the likelihood of actionable outcomes. It also demonstrates the types of considerations that are imperative for effective delivery and implementation in out-of-school time settings.


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More About This Work

Academic Units
Behavioral Nutrition
Thesis Advisors
Contento, Isobel R.
Ph.D., Columbia University
Published Here
August 17, 2017