In Defense of Food Curriculum: A Mixed Methods Outcome Evaluation in Afterschool

Abstract

Background. Highly processed foods are inexpensive and abundant in our food supply, nutritionally poor, and disproportionately marketed to minority youth. This study is part of a curriculum development project to develop, implement, and evaluate the In Defense of Food (IDOF) curriculum designed to increase intake of whole/minimally processed foods and decrease intake of highly processed foods in youth. Aims. This pilot outcome evaluation was undertaken to assess initial effectiveness and to provide an in-depth understanding of changes in behavioral outcomes and psychosocial mediators. Methods. We used an explanatory mixed method approach, including a single-arm pretest–posttest of intervention effect, followed by a food rules assessment and in-depth interviews to describe participant responses to the intervention in more detail. The study was conducted in three afterschool classrooms in urban low-income neighborhoods with 32 multiethnic middle-school youth, receiving 10 weekly 2-hour sessions. Results. Two weeks postintervention, there was a large positive significant increase in whole/minimally processed food intake (p < .01; d = 0.59) and a small decrease in consumption of highly-processed foods (p = ns; d = 0.06), compared with baseline. Significant increases in psychosocial mediators: Self-efficacy and positive outcomes expectations were seen; others were not significant but changed in the desired direction. Qualitative assessments suggest that the intervention promoted skill building, but environmental barriers made these difficult to use. Discussion. The IDOF curriculum may be most effective for promoting consumption of fruits and vegetables, rather than decreasing intake of highly processed foods. In addition, in this young age-group, short actionable food rules may support self-regulation and behavior change. Conclusion. Among adolescent students in low-income urban neighborhoods, the IDOF afterschool curriculum may help promote self-efficacy and positive outcome expectancies and increase fruit and vegetable intake. Focusing on food processing and using “Food Rules” may be promising to elicit behavior change in youth; however, greater supports are needed to overcome social and environmental barriers.

Keywords

adolescents health education nutrition outcome evaluation

It is commonly accepted that the current “Western” lifestyle is contributing to the pandemic of chronic diet-related diseases in the United States (Amine et al., 2002; Gootman, McGinnis, & Kraak, 2006; World Cancer Research Fund & American Institute for Cancer Research, 2007). A shift in diet quality and increased rates of diet-related diseases correspond with the rapid increases in and availability of “fast” or “convenience” ready-to-eat and ready-to-heat highly processed foods (HPF) and drink products (Popkin, 2006; Poti, Mendez, Ng, & Popkin, 2015).

“Processed foods” are defined as foods (other than raw agricultural commodities) that are classified based on the extent to which they have been altered from their natural state (Dietary Guidelines Advisory Committee, 2015). All foods exist on a spectrum of processing from unprocessed or minimally processed, like fresh fruits or milk, to those that are highly processed (containing multi-ingredient, industrially formulated mixtures), as found in most fast foods and packaged convenience foods (Poti et al., 2015). On average, HPFs have a higher proportion of fat, sugar, and salt compared with less processed versions (Poti et al., 2015); they are substantially cheaper than more healthful options (Drewnowski & Darmon, 2005; Drewnowski & Specter, 2004); and tend to lead to a greater consumption of overall calories (Chandon & Wansink, 2012; Poti et al., 2015). Emerging research indicates that diets predominated by HPF tend to be nutritionally poor compared with those composed of mostly whole foods (Moubarac et al., 2013; Poti et al., 2015).

American youth can easily access and select HPF, which are cheap and abundant in the food supply and heavily marketed to them. Billions of dollars per year are spent by the food industry marketing highly processed junk food to young people—a vulnerable population who are unable to fully understand the persuasive intent of marketing strategies. Furthermore, Black and Hispanic youth are disproportionately targeted by the food industry, which has direct impacts on their selection and consumption of these foods (Cairns, Angus, Hastings, & Caraher, 2013; Harris et al., 2013; Harris et al., 2015).

Rather than pinpointing a particular nutrient or an individual food as the culprit of the health complications that adolescents are facing, it is becoming increasingly clear that a number of behaviors that define a dietary pattern, such as whether a person consumes a large amount of various processed foods (sugar-sweetened beverages, processed-packaged snacks, and fast food) compared with whole foods (fruits and vegetables [FV]), may influence whether a person can maintain energy balance and optimal health over the long term (Baranowski, Cerin, & Baranowski, 2009; Moreno et al., 2010; Popkin, 2006; Poti, Duffey, & Popkin, 2014).

Although processed foods have come to dominate the American diet, few nutrition initiatives aim to specifically and explicitly provide the message to eat less HPF. Among those who have brought to the attention of the American public the importance of healthy eating patterns, as opposed to a focus on individual nutrients, is Michael Pollan. His book, In Defense of Food (Pollan, 2008), highlights the dietary approach of eating less HPF and more whole/minimally processed plant-based foods.

This study provides a pilot outcome evaluation for the In Defense of Food (IDOF) curriculum (Bhana, Koch, Uno, & Contento, 2016) for afterschool, based on Pollan’s book In Defense of Food and aimed at decreasing intake of HPF and increasing intake of whole/minimally processed foods (W/MPF) in youth. The aim of the study is to assess initial efficacy and to provide an in-depth understanding of the potential behavioral outcomes and psychosocial mediators of youth participating in the curriculum. This study is part of a larger curriculum development project, described elsewhere, composed of an initial curriculum development assessment (Luesse & Contento, in press), a detailed description of the development of the curriculum (Luesse, Koch, & Contento, in press), and its process evaluation (Bhana, 2017).

Method

Study Design

The outcome evaluation utilized an explanatory mixed-methods approach (Creswell & Plano Clark, 2007) in which pretest–posttest survey data were collected, followed by open-ended one-on-one assessments and semistructured in-depth interviews. The Program Evaluation Lifecycle conceptual framework was considered to ensure the alignment of the program lifecycle and evaluation lifecycle (Scheirer et al., 2012; Urban, Hargraves, & Trochim, 2014) by matching a mixed methods pretest–post approach to the early life stage of the program. This framework suggests that the evaluation of a program should match the stage of development of the program. Programs at their initial stages of development and implementation are undergoing rapid and often substantial changes and therefore should be accompanied by evaluation plans that emphasize internal consistency, measure implementation factors, and select outcomes within intervention groups, rather than between groups, to ensure more effective and efficient use of resources (Bowen et al., 2009; Urban et al., 2014; Zapka, Goins, Pbert, & Ockene, 2004). At the early stages of development and evaluation of a health promotion program, modifications and adjustments based on a new program’s application to a new setting and population may be apparent. Thus, a range of evaluation levels (e.g., process and outcome) are often suggested to strengthen the ability to accurately measure outcomes (Kozica, Lombard, Hider, Harrison, & Teede, 2015).

IDOF Curricular Components

Overview

IDOF is a health education curriculum for youth (Grades 6 to 8) designed for an afterschool setting. The principal author with the support of a curriculum development team at Teachers College, Columbia University, developed the IDOF curriculum (Bhana, 2017; Bhana et al., 2016). It consists of 10 sequential 2-hour educational lessons and is the companion guide to the Public Broadcasting Services documentary film In Defense of Food based on Pollan’s best-selling books In Defense of Food (Pollan, 2008) and Food Rules (Pollan, 2009).

The curriculum was designed to help youth become critical of the corporate food supply and familiar and confident to select and prepare W/MPF. In doing so, the curriculum aims to challenge students’ current perceptions of what “food” is by combining activities that have “shock appeal,” such as unveiling cunning marketing strategies, along with preparing and eating W/MP dishes with the objective of making these foods fun and cool.

The lessons are structured into three units, consisting of three lessons each, followed by a final celebration lesson, that highlight a particular concept related to Pollan’s seven-word axiom for healthy eating (Eat food. Not too much. Mostly plants). Table 1 provides a detailed outline of the curriculum and its components.

Table 1.

Description of In Defense of Food Curriculum Components.

Unit	LessonGeneral Objective	Lesson overview	Food rule(s)	Examples of coordinating activities	Film clip synopsis	Mediators
EAT FOOD	L1: Where are the soda trees?: Students are introduced to the In Defense of Food curriculum and the concept of foods versus phuds.	Students learn to differentiate foods from phuds and how eating healthfully can help them do better at the things that are important to them (e.g., dancing, playing football).	Eat food you can picture growing in nature.	• Students jot down things that are important to them. • In small groups, they sort picture cards of foods and phuds as those that can be pictured growing in nature—those that can help them with the things that are important to them. • Food tasting—students taste seeds. • Phud Farm Skit—in small groups, students create a spoof of phuds that would “grow” on a farm.	Meet Anthony Scavotto: Anthony is a young adolescent who suffers from health complications related to excess weight gain. Even though he and his family thought they were eating healthy, they were still eating mostly phuds, and it has had effects on his ability to play the sports that he loves.	• Positive/negative outcome expectations • Food and nutrition skills • Self-efficacy
	L2: Chemical cuisine: Students increase their awareness of the benefits of eating more foods and fewer phuds.	Student compare ingredients in a homemade versus highly process version of a cookie, and then other food and phud product ingredient lists, to discover that phuds are not always what they appear to be.	Eat foods with ingredients that a third grader could pronounce.	• Students learn about ingredients through a cookie relay race game.• In a gallery walk around the classroom, students examine different ingredient lists and then cast ballots guessing what the product is.• Phud tasting—students taste candy with temporarily altered taste buds to discover what a popular candy tastes like without all the excess sugar to mask its other ingredients.	Salt, Sugar, Fat: The Western diet is made up of highly processed foods, full of salt, sugar, and fat, which leads to big profits for food companies but poor health for people. Learn about how highly processed foods are engineered to be irresistible.	• Food and nutrition skills• Negative and positive outcome expectations
	L3: The Claim Game: Students explore how companies use marketing strategies on food packaging to get us to buy products.	Product packages are designed so that the phuds/foods within them look irresistible and seem healthier than they are. Now that students have looked inside the packages (in lesson 2), they are ready to examine the outside of the packages.	Avoid products that make health claims.	• Students play a word association game to highlight how engrained marketing for phuds is in the meaning we attribute to certain phuds.• Students examine product packages critically for “tricky techniques” employed to get people to buy them.• Food tasting—students taste unique fruits that come in fun “packages” of their own.• Making action plans to eat fewer phuds.	Phud Phads: Magic bullet answers to health can often create phud phads and more confusion about what to eat to be healthy. Take a historical journey of ancient fads that made knowing what to eat to be healthy just as confusing as it is now.	• Food and nutrition skills• Negative and positive outcome expectations• Goal intention
NOT TOO MUCH	L4: Don’t be phoooled: Students examine how food advertising and marketing writ large influence us, often on a subconscious level.	We can’t escape advertising, it is everywhere, and it is persuasive. Building on what students learned about marketing techniques, this lesson dives deeper into its impacts on our food choices.	Avoid foods you see advertised on television.	• Play a logo game to see how easily recognizable popular brands’ logos are.• Share “Capture It” pieces, a creative reflection on phuds they want to eat less of.• Persuade your peers—students create persuasive arguments for funny scenarios.• Examine phud ads for its persuasive intentions.• Create a food ad.	Marketing Low Fat: The science of eating low-fat foods was hijacked by food marketers producing scores of processed food products thought to be healthy because they were low fat (despite being high in sugar) and creating greater consumer confusion.	• Negative outcome expectations• Self-efficacy• Food and nutrition capability
	L5: Supersized: Students become aware of how our food environment influences when, what, and how much we eat.	Even though most people think that they eat only until they are full, there are many environmental cues that strongly influence how much, when, what, and why we eat; the size of the container that food/drink comes in is one such example. Students explore how large container sizes can lead us to eat more than we should.	Choose smaller plates and cups.	• A popcorn experiment demonstrates that the size of the bag that students serve themselves in influences how much they take and will later eat.• Measuring out liquids with different-sized containers.• Food tasting—making flavor shakers for homemade popcorn.• Action plans to eat smaller portions when phuds are chosen.	Serve More, Eat More: When food and drinks are served in large containers, we tend to consume more, even when we’re not hungry/thirsty. Food companies use this strategy to sell more products. Health promotion specialists are using similar “tricks” to help eat less and choose healthier options.	• Negative outcome expectations• Self-efficacy• Food and nutrition skills• Self-regulation skills
	L6: Dia-beat it!: Students understand that eating phuds instead of foods can increase their risk of getting sick.	Type II Diabetes is on the rise, especially in poor and minority subgroups. Students learn about commonly consumed phuds and the amount of sugar they have in them and what that does to the human body.	Make water your beverage of choice. Sweeten and salt your food yourself.	• A visualization activity to see how diabetes mellitus type II prevalence has changed.• Counting out sugar in popular snacks and beverages.• Food tasting—make homemade ginger ale.• Action plan to eat less sugary phuds.• Create a spoken-word poem.	Sugar Flood: An animated story reveals what happens to your body when you consume excess sugar in the short term and chronically.andDiabetes: An Epidemic: A young African American spoken-word poet collaborates with health care works to raise awareness about the connection between unhealthy diets and rising rates of diabetes mellitus type II. In her poem, Death Recipe, she acknowledges the power of phuds and reveals familial tragedies that she has experienced firsthand.	• Negative and positive outcome expectations• Food and nutrition skills• Self-regulation skills/autonomy support
MOSTLY PLANTS	L7: Rooting for plants: Students become more familiar with and excited about eating plant-based foods.	Students taste and gain experience in preparing all the different parts of the plant to help them eat more plants.	If it came from a plant eat it; if it was made in a plant don’t.	• Play a guessing game using close-up photos of different fruits and vegetables.• Make a plant part salad with all parts of the plant (leaves, seeds, stems, flower, roots, and fruit).• Action plan to eat “mostly plants.”	Going Farming! In certain neighborhoods, finding fresh, healthy, and affordable plant-based foods is difficult. See how a school in the Bronx is responding by giving students opportunities to get excited about growing, preparing, and eating plant-based foods.	• Positive outcome expectations• Functional/procedural knowledge• Self-efficacy• Self-regulation skills/autonomy support
	L8: Color Your World: Students build confidence and desire to eat plant-based foods.	Eating a variety of plant-based foods of all colors is important. Students learn how with more tasting and food preparation experiences.	Eat your colors.	• Guessing game for various fruits and vegetables of all colors.• Share “Capture It” pieces about a plant-based food they had an experience with at home or in their community.• Action plan to eat more fruits and vegetables of all colors.• Food tasting—make a five-color salad.	Vegetable Surprise: When students are involved in producing fruits and vegetables, they are more likely to try them. Students at a summer camp make homemade pizzas topped with a variety of familiar and unusual vegetables from the garden.	• Positive outcome expectations• Functional/procedural knowledge• Self-efficacy• Self-regulation skills/autonomy support
	L9: Lettuce Turnip the Beet: Students create practical strategies to continue following the Food Rules.	Students use what they have learned thus far and apply it to different scenarios taking tips from other cultures that eat more healthfully than we do.	Eat more like the French do.	• Explore how different cultures eat plant-based foods.• Solves challenges to eating healthfully by reviewing different scenarios.• Action plan—taking action to eat more plant-based foods at home.• Food tasting—plant-based parfaits.	Secrets of the French: Culture can be a powerful lever in shaping how we eat. French traditions and customs help the French eat well and stay healthy. They eat at regular times, have routines, share food together, eat small portions, and slowly enjoy their foods.	• Positive outcome expectations• Functional/procedural knowledge• Self-efficacy• Self-regulation skills/autonomy support
CELEBRATE	L10: Eat food. Not too much. Mostly plants.: Students celebrate and share what they have learned throughout the In Defense of Food curriculum.	If you eat whole plant-based foods most of the time, it’s ok to break the rules once in a while as well. Students learn that eating well is about enjoying treats on occasion too and have a pizza party to celebrate all that they have learned.	Break the rules once in a while.	• Students share culminating projects with their peers.• Students write out advice cards based on what they learned to be healthy for other students who have not taken this course.• Food tasting—pizza party!	Join the Movement: There is a food movement happening around us, and all across the country people are getting together to grow food and advocate for healthier, local, and affordable foods.	• Positive outcome expectations• Functional/procedural knowledge• Self-efficacy• Self-regulation skills/autonomy support

Note. The lessons are structured into four units: Eat Food; Not too Much; Mostly Plants; and Celebrate. Lessons 1 to 3 (Eat Food) explore the differences between food (whole/minimally processed food) and highly processed food products, phuds. Lessons 4 to 6 (Not Too Much) explore the health consequences of eating too much (in general and too many phuds) and guides students to create plans to make realistic changes in their own lives. Lessons 7 to 9 (Mostly Plants) guide students to look at what it means to eat mostly plants and spend time cooking and tasting healthy plant-based meals and snacks together. The last lesson encourages a celebration of food.

Food Rules

Each lesson provides a take away “Food Rule” to help youth put the lesson’s theme into action. For example, Lesson 5 presented the food rule “Choose smaller plates and cups,” helping youth eat smaller portions of HPF.

Film Clips

Each lesson also introduces a film clip from the documentary film to reinforce the themes and messages of the lesson and provides opportunities for thoughtful discussions.

Food Preparation/Tastings

Most lessons provide a food preparation/tasting component to introduce youth to tasty and healthful foods and provide them with the skills to select and prepare W/MPF.

Goal Setting

Most lessons provide youth with goal-setting and self-regulation skills by having them complete written action plans aimed at developing specific, actionable, and measurable goals to eat more W/MPF and eat fewer HPF.

The IDOF Theoretical Model

The curricular objectives are grounded in the social cognitive theory (Bandura, 1986) and the self-determination theory (Deci & Ryan, 1985) mediators (also referred to as determinants) of positive and negative outcome expectations, attitudes, goal intention, factual/procedural knowledge and skills, self-efficacy, autonomous motivation, and self-regulation skills. Self-efficacy, outcome expectations, and self-regulation skills have been cited in the literature as predictive of health behavior change as it relates to FV and decreasing sugar and fat intake in adolescents (Dewar, Lubans, Plotnikoff, & Morgan, 2012; Schnoll & Zimmerman, 2001).

The behavioral outcomes are to increase intake of W/MPF, operationalized as FV, and decrease intake of HPF, operationalized as sugar-sweetened beverages, fast foods, and processed-packaged snacks.

Teacher Training and Curriculum Implementation

The study was conducted over a 14-week period in the fall of 2015; lessons were taught by the regular afterschool program teachers, one lesson/week, over 10 weeks. Prior to implementing the curriculum, study investigators conducted a 2-hour professional development training for all the teachers from the participating sites. Teachers were given an additional hour of training 2 weeks into the curriculum and further support as needed throughout the curriculum delivery period.

Recruitment and Participation

We distributed recruitment flyers in person to afterschool program directors (n = 70); 15 expressed interest in participating in this study. Sites that included an afterschool program accommodating low-income, minority middle school–aged youth and could facilitate weekly 2-hour lessons were invited to participate in the study. Initially, four sites were eligible and expressed continued interest; however, two dropped out before the start of the intervention for scheduling and logistical reasons. The remaining two afterschool program sites in low-income neighborhoods in New York City were enrolled in the study to offer the curriculum across three classrooms (one classroom at Site 1 and two classrooms at Site 2). All procedures, surveys, and protocols were approved by the Teachers College, Columbia University review committee on the protection of human participants. Parents consented to student participation, and students provided informed assent. All enrolled youth at the two respective sites received the IDOF curriculum; however, only those with written parental consent were included in the evaluation. Participating youth and teachers received a gift valued at $20 for their time.

Description of the Outcome Evaluation

A flowchart is presented in Figure 1.

Figure 1.

A mixed methods study flowchart.

Instruments and Data Collection and Analysis

Pretest–Posttest Survey

A self-report previously validated instrument, FHC-Q (Gray, Koch, Contento, Bandelli, & Di Noia, 2016), was modified for this study, mFHC-Q, (approximately 55 minutes), measuring frequency of W/MPF and HPF intake; six hypothesized theoretical mediators of W/MPF and HPF intake (described below); and demographic variables (age, ethnicity, and gender). The survey was administered with students a week prior to and 2 weeks after the delivery of the curriculum using an electronic audience response system.

The food and beverage behavioral outcome items in the FHC-Q were adopted from the Beverage and Snack Questionnaire (BSQ; Neuhouser, Lilley, Lund, & Johnson, 2009) previously validated in middle school–aged youth against 4-day food records. The psychosocial mediators in the FHC-Q, included in the mFHC-Q, underwent two cognitive testing sessions with elementary school-aged children to ensure student’s understanding of the survey questions as well as for test-retest reliability testing (Gray et al., 2016).

Each behavior or mediator was represented by a scale with three to nine items. Questions for behavioral outcomes were asked with the stem, “In the past week, I ate/drank . . .,” and response options included “0 times,” “about 1-2 times,” “about 3-4 times,” “almost every day,” and “2 or more times every day.”

Items measuring fruit and vegetable intake (e.g., apples, broccoli, carrots) and highly processed food intake (e.g., fast food, sweetened beverages, processed-packaged snacks) were presented with a picture of the foods or beverages being assessed.

For the psychosocial mediators, items used a 5-point Likert-type scale with scores ranging from 1 to 5 (with higher scores reflecting more of each construct). Specific mediators related to the target behaviors included positive and negative outcome expectations (e.g., Eating FV helps my body do what I want it to do; Drinking sweetened beverages contributes to my developing diabetes), self-efficacy (e.g., I am sure I can eat vegetables at dinner), attitudes (e.g., Eating FV is important to me), and goal intention (e.g., I would like to eat more FV). General mediators, those related to health behavior change overall, included self-regulation skills (e.g., I know how to keep track of my food intake) and autonomous motivation (Eating healthy is an important choice I really want to make).

Pretest and posttest data were analyzed using the Statistical Package for the Social Sciences (SPSS), v24 (2016). Mechanical errors with the audience response system in pretest and suboptimal Cronbach’s alpha coefficient values led to the removal of goal intention and attitudes from analysis. Cronbach’s alpha coefficient values for all remaining mediators ranged from 0.72 to 0.90 rendering a 46-item questionnaire for analysis. We calculated descriptive statistics and used paired t tests to evaluate baseline to postintervention changes in behavioral outcomes and psychosocial mediators. We used Cohen’s d to calculate effect size by taking the mean difference between pre and post values and dividing by the standard deviation for each behavioral outcome and psychosocial mediator.

Food-Rule Assessment

We applied an analytic rubric to assess the depth of comprehension that students need to demonstrate understanding (Allen & Tanner, 2006) of each of the 11 Food Rules when provided the assessment prompt “What does this Food Rule mean? How would you use this Food Rule?”

The lead investigator (female) conducted the Food-Rule assessments using the two aforementioned open-ended questions with a subsample of the cohort (represented from each classroom and selected based on high attendance throughout the program). All Food-Rule assessments were held in a private room at each site over a 2-week period after curriculum delivery, administered after the posttest assessment to reduce any potential bias, and lasted for approximately 15 minutes. Extensive paper-and-pencil notes and audio-recordings were used to capture student responses; audio-recordings were transcribed for pertinent information, and written notes were reviewed for accuracy against the audio-recordings.

The lead investigator and a trained research associate (male) reviewed three transcripts before coming to a consensus on the scoring rubric and achieving a chance-corrected (kappa) interrater reliability of .817 (Landis & Koch, 1977; Viera & Garrett, 2005). A total score was determined based on an assessment of each of the 11 Food Rules for each participant and by each Food Rule thereby measuring how well a particular participant understood the Food Rules overall and how well a particular Food Rule was understood. A participant-level score was generated by summing the participant’s individual 11 Food Rules scores (scored on a 1 to 3 scale: 1 = no comprehension, 2 = good comprehension, and 3 = high comprehension) divided by the total possible score that could be achieved (33 points). The coders grouped participants into three categories—low comprehension, moderate comprehension, and high comprehension—based on substantively driven cut-points ≤0.60 (≤20/33 points) = low; >0.60 to <0.80 (>20/33 points to 26/33 points) = moderate; >0.80 (>26/33 points) = high. These cut-points were determined based on standard cutpoints used to assess competence and learning in education.

Second, the coders generated a total score for each Food Rule across the cohort by summing each participant’s score for a particular Food Rule, divided by the total possible scores that could be reached. We imported qualitative notes into NVivo11 (QSR International, Melbourne, Australia, 2015) for analysis and reviewed them for emergent codes within each comprehension group and across the sample.

Semistructured Interview

The lead investigator created an interview script including six open-ended core questions, probes, follow-up questions, and member checks during the interview. Questions aimed to understand the target mediators and behavioral outcomes, for example, asking about “outcome expectations” (What are the benefits of eating fruits and vegetables?) or “attitudes” (What are your thoughts and feeling about eating phuds?)

A purposeful sample (two to four participants from each classroom) was selected to capture a range of participants observed to demonstrate varying degrees of understanding of the material. Thirty-minute interviews were held in a private room at each respective site and was led by the lead investigator (female) who has experience conducting interviews with adolescents. All interviews were audio-recorded.

Interviews were transcribed verbatim by an outside source and reviewed with their original audio recordings a minimum of two times to ensure accuracy. The lead investigator reviewed transcripts beginning with an open-coding process using line-by-line coding to identify themes, patterns of words, perceptions, and ideas, which were then classified into categories. An initial codebook of themes included a priori themes based on the target mediators from social cognitive theory and self-determination theory and emergent themes. Two independent coders met to review the coding scheme after reviewing two transcripts together, and the lead investigator and a trained research associate (male) met to come to a consensus on their codes after coding 3 of the 12 transcripts. Discrepancies between coding pairs were resolved through discussion to generate the final coding scheme. A percent agreement of 85% across coding pairs indicated acceptable levels of reliability. Each interview transcript was imported into the qualitative software NVivo 11 (QSR International, Melbourne, Australia, 2015), and themes were extracted from the imported text files and coded in NVivo.

Results

A total of 32 participants (n = 2 lost to attrition; 94% response rate) completed the surveys at both pretest and posttest. A subsample of this group was selected for the qualitative assessments. Demographic characteristics of participants grouped by assessment (pretest/posttest, Food Rule assessment, and interviews) are presented in Table 2. Overall, the mean age of participants was 12 years ± 0.62, 50% (n = 16) were female, and 56% were Black/African American. See Table 2 for demographic characteristics.

Table 2.

Descriptive Characteristics of Study Sample by Assessment.

Variable	Completers (n = 32)	Dropouts (n = 2)	Food rule assessment (n = 22)	Interviews (n = 12)
Gender
Female, n (%)	16 (50)	2 (50)	14 (63.6)	6 (50)
Age, years, M ± SD	12.06 ± 0.62	11.5 ± 0.70	12.00 ± 0.62	11.92 ± 0.67
Ethnicity, n (%)
Hispanic	11 (34.4)	2 (100)	9 (40.9)	4 (33.3)
Black	18 (56.3)	—	11 (50)	7 (58.3)
White	1 (3.1)	—	1 (4.5)	1 (8.3)
Mixed	2 (6.3)	—	1 (4.5)	—

Behavioral Outcomes and Mediators

There was a significant increase in mean frequency of FV intake at posttest compared with pretest (t = 3.359, p < .01)—an effect size that is considered to be large (d = 0.59). Small effect sizes (d = 0.34) were seen for mean intakes of HPF but change in score was not statistically significant (p = .06).

Statistically significant increases in outcome expectations and self-efficacy for FV intake occurred from pretest to posttest; all other mediators showed no statistically significant changes (Table 3).

Table 3.

Behavioral and Psychosocial Mediator Outcomes for Participants From Pretest to Posttest.

Measure	M (SD)		Effect size, Cohen’s d	Statistics, t (df)	p	Internal consistency, Cronbach’s α
Measure	Pre	Post	Effect size, Cohen’s d	Statistics, t (df)	p	Internal consistency, Cronbach’s α
Behavioral outcomes
FV intake (8 items)	1.70 (0.63)	2.15 (0.60)	0.59	3.359 (31)	<.01	0.76
HPF intake (9 items)	3.20 (1.23)	2.76 (1.02)	−0.34	−1.919 (31)	.06	0.89
Mediators
Outcome expectations (FV) (3 items)	2.7 (1.4)	3.6 (1.1)	0.45	2.559 (31)	.02	0.85
Outcome expectations (HPF) (4 items)	4.2 (1.2)	3.7 (0.9)	−0.27	−1.529 (30)	.14	0.79
Self-efficacy (FV) (5 items)	2.8 (1.2)	3.5 (1.0)	0.47	2.642 (30)	.01	0.76
Self-efficacy (HPF) (8 items)	3.2 (1.3)	3.5 (0.9)	0.15	0.837 (30)	.41	0.89
Self-regulation skills (general) (3 items)	3.5 (1.3)	3.4 (1.1)	−0.07	−0.418 (31)	.68	0.72
Autonomous motivation (general) (3 items)	3.8 (1.4)	3.8 (1.2)	0.01	−0.041 (30)	.97	0.82

Note. FV = mean frequency of fruit and vegetable intake; HPF = mean frequency of highly processed food intake. Effect size is based on change in frequency (number of times FV and HPF were consumed per week). Change in FV intake translated to an increase in approximately 0.75 servings/day; changes in HPF translated to a decrease in approximately 1.8 servings/day.

Food-Rule Assessment

A total of 22 participants were included (64% female; mean age of 12 [± 0.62]; 40.9% Hispanic, 11% Black, and 9% White/Other); 66% of the participants were categorized into the high comprehension group (18% in the moderate and 18% in the low) based on their summative food-rule assessment scores. Qualitative subgroup analysis among the high comprehension groups revealed the demonstration of the application of self-regulation skills, which was not seen with any members of the low comprehension group; no notable themes emerged among the low comprehension group.

Analysis by Food Rule revealed some rules were better understood (e.g. “Break the rules once in a while,” “Make water your beverage of choice”) and others were less-well understood (e.g. “Avoid products that make health claims”; “If it came from a plant, eat it; if it was made in a plant, don’t”). Subgroup analysis revealed that youth demonstrated an application of self-regulation skills for the highest-ranking Food Rules (those most understood); no themes emerged across the lowest-ranking Food Rules.

Table 4 presents illustrative quotes from each Food Rules grouping. Figure 2 presents each Food Rule ranked from highest to lowest in scores.

Table 4.

Illustrative Quotes From Food Rules Assessment Demonstrating Self-Regulation Skills.

Food rules grouping	Illustrative quotes	Food rule applied
High comprehension group	I pick a day in the week that . . . you can pick sweet foods, like every Friday.	“Break the rules once in a while.”
	Take small portions of food. Instead of a bag of chips, take a handful.	“Choose smaller plates and cups.”
	If you choose bigger plates, it makes you eat more; I would get a smaller plate and eat less junk.	“Choose smaller plates and cups.”
Well-understood Food Rules	I drink water more than soda. I drink water 3 times a day.	“Make water your beverage of choice.”
	Drink water instead of juice. When I’m at my house, I choose water.	“Make water your beverage of choice.”
	You can eat phuds once in a while, but not every day. Twice through the week; like I eat phuds only twice through the week.	“Break the rules once in a while.”
	You can eat something that’s unhealthy but once a week. Like if every day you eat fruits and vegetables, one day you can eat sugar snacks.	“Break the rules once in a while.”

Note. Illustrative quotes demonstrating the application of self-regulation skills generated by participants categorized in the high comprehension group (>0.80 [>26/33 points] = high), and for the most well-understood Food Rules. Self-regulation was defined as the use of goal setting/action plans, self-assessment, and planning and included strategies to avoid, moderate, remind, encourage, track, reward, and substitute for undesired for healthy behaviors (Bandura, 1986; Contento, 2016; Ryan & Deci, 2000).

Figure 2.

Distribution of scores for each Food Rule.

In-Depth Interviews

Table 5 provides themes and illustrative quotes from the semistructured interviews with the 12 participants (50% female; mean age 11.92 ± 0.67 years; 33% Hispanic, 58% Black, and 8.3% White/Other). Youth discussed supports for eating FV, including social support and modeling, the application of self-regulation skills to increase intake, and their expressed preferences for FV. They discussed the application of self-regulation skills, critical thinking skills, and strategies to decrease salience of HPF but revealed that the social and physical environment made it difficult to do so. Youth were also preoccupied with the negative physical outcome expectations of eating HPF, such as developing diabetes.

Table 5.

Themes and Illustrative Quotes From In-depth Interviews.

Themes	Illustrative quotes by subtheme
Self-regulation skills and W/MPF: Youth discussed the self-regulation skills that they adopted as a result of participation in the program.	“I decided to make like a schedule at home, like what should I eat most of the time, so I should eat foods . . . more than phuds. So my mom helped and we made this chart and it showed me how much I ate . . . food than phuds. So we will always have to check to see if I am doing good because my mom wants me to, like be more healthier.”“My schedule does [helps me eat W/MPF], because you know, I tell to my mom about it so she said: yes and say it to help me more. In the beginning, like, there was like a chart with foods and phuds and like, we always had to color, like in marker, to see how much foods I was eating so like, sometimes for snacks, I would always eat like fruits, because you know, they are like, we didn’t really buy them much before. And I would always check my chart and I would open up a note and like for, today . . . of phuds I am like up to here [gesture of a small amount] and like for my fruits I am like up to there [gesture of a large amount], but like every single day I keep on going up and up and up, more fruit.”
Preferences for W/MPF: Youth discussed a change in preferences for FV and “healthy” foods.	“My mom usually cooks something that’s like with veggies. She gives us a lot of like vegetables, and vegetables and curry. And before I used to say yuck, but now she says I’m eating them a lot now.”“I eat more greens because I don’t think that they are just going to taste nasty. So, I never ate them before but now I’m eating them . . . they taste better.”“We made a . . . so one time we made a salad and I think that was very good so and also we made a yoghurt, that was also good. So, I was like, maybe eating healthy is, like good.”
Social support/modeling for W/MPF: Youth frequently indicated that their parents/family members supported them by providing FV at home and helping them make healthy food-related decisions.	“I get real foods when I go shopping with my mom, where I can get anything I want. Cuz we used to eat a lot of phuds, like we’d get takeout or fried foods, a lot! And . . . we talk about things when we go to the grocery store, like when we look at the cereals and stuff. With my mom, I told her that we shouldn’t have anything with sugar over . . . like over . . . 15 um 15 grams or if it has a lot of like, weird ingredients in it. We usually get a lot of food, like fruits and vegetables, like oranges and broccoli.”“Like when my mom goes food shopping, I don’t pick up a lot of snacks no more, I like to pick fruits and vegetables, not only vegetables, a lot of fruits.”“I eat a lot because when I told my mom about this program, she was like . . . she bought a lot of fruits and vegetables for the house.”“My mom and some of my friends [helps me eat W/MP foods]. Because basically I am always with my mom so she always tell[ing] me you’ve got to eat this and sometimes I say, I don’t want to but she forces me to.”
Negative outcome expectations of consuming HPF: Participants discussed risks associated with eating HPF, such as becoming diabetic or gaining weight. Most discussed diabetes through a personal fear of the outcome, through association (e.g., how a family member suffers from it), or as was discussed in the curriculum in relation to activities they engaged in.	“I don’t want to die because I have diabetes and when I think about this it’s like, I get this, or shall I get this? Do I take these cookies or should I get this fruit? I don’t know.”“They showed us some videos and in one of the videos this girl was talking about how she used . . . how her family used to eat and they got diabetes and stuff. And I don’t want diabetes.”“[When I see phuds, I think] I don’t want to get fat.”“Because we watched a show [curricular video] about diabetes, lots of phuds [HPF] show up in diabetes and if you keep on eating them you will really get diabetes. That’s what scared me.”
The environment and HPF: Participants found their environments (physical and social) were challenging and hindered their ability to eat fewer HPF. Their social environment (e.g., whether family or friends consume HPF at home, school, and in their neighborhoods) and their physical environment (temptations offered by food marketing and access/availability) were commonly discussed as challenges to eating fewer HPF.	Social norms: “[What makes it hard to resist HPF] I think it’s school. My friends . . . cuz, they eat it.”“My dad [makes it hard to resist HPF]. By buying junk food from the supermarket, buying Doritos’ and Lays and all that.”“Because they [classmates and friends] eat Phuds [HPF].”Marketing of HPF: “Like if you . . . just saw an advertisement for how they [HPF] taste so good and then you see an orange but they make the burger look so good and then it throws off the orange. It throws the orange off, the sandwich thing. I’ll go with the sandwich.”Neighborhood access: “Like whenever I go to the store I always see like, it’s a whole aisle of phuds [HPF]. When you are like, I am trying my best to resist it but it’s like something telling me to buy it, buy it, buy it.”“It’s easy for me to eat my rice and apples and pears and stuff because those are the things that are in my house and then if we go out there’s like pizza and salad and it’s more hard for me. Because it’s like pizza is good and salad is good, and you can’t choose both.”“It’s just that I see a bunch of snacks and snacks and snacks!”
Overcoming challenges: Participants discussed the application of self-regulation skills, demonstrating an ability to think critically to rationalize resistance to HPF and implementing strategies to influence the salience of HPF.	Self-regulation: “I watch how much snacks I eat. Because like if it’s like pizza, I would take like two slices instead of like four. I see how much it is and I am like, I decide the minimum size I can have.”“I actually don’t get them [HPF] all the time. I only get them once, like on Fridays.”Critical thinking skills: “I feel like I want to have it but I don’t want to have it because I know what’s in it and how it’s made.”“[Something she thinks about] How did they [food companies] just put them together and make it taste good? That makes it so tempting. So, it’s just that we can buy it more.”
	Salience: “Like, I don’t know, like say I got cookies right here, or a chocolate or whatever, like if I get this and I am thinking of me in the future how I would look fat and if I get this bag of apples or whatever it’s like I picture me like slim. So, I pick the one what I want to look like in the future.”“Sometimes, when I really hungry, it’s hard . . . then I think, I’ll get fat, or I just keep on walking [holds hand to cover eyes]. I think I could spend my money more wisely and drink water instead of soda and get . . . um . . . like, sunflower seeds instead of chips.”“Well, . . ., I could not look at the brand or not look at the picture because it encourages me . . . encourages me to eat it. And I know when I have a phud, I should get just a little. And sometimes, I just try to think about something else.”“I keep . . . gain control over it. When I see chocolate, I just walk away from it.”

Note. W/MPF = whole/minimally processed foods; FV = fruits and vegetables; HPF = highly processed foods.

Discussion

The aim of the IDOF curriculum is to improve eating behaviors by increasing intake of W/MPF, operationalized as FV, and by decreasing intake of HPF. The current study is a pilot evaluation and part of a larger curriculum development project (Bhana, 2017). This study is not an efficacy trial, and a control group was purposefully not selected to allocate resources toward a richer understanding of the program’s outcomes through both qualitative and quantitative methods at this early phase of evaluation (Urban et al., 2014).

Behavioral Outcomes

Findings from this study demonstrate that youth participating in the IDOF curriculum increased their intake of FV with a large effect size. While a statistically significant change in HPF intake was not seen, there was a small effect size in the direction hypothesized. These findings are based on changes in frequency of consumption per week. Participants reportedly consumed FV only one to two times per week at baseline, which increased to approximately three to four times per week. Although these changes generated large effect sizes, the magnitude of change is low in comparison with dietary recommendations that encourage consumption of three to five servings per day (U.S. Department of Agriculture, 2012). The effect sizes obtained in this study have been demonstrated in comparable studies with children and adolescents in school-and-afterschool-based settings (Diep, Chen, Davies, Baranowski, & Baranowski, 2014; Thompson et al., 2009; Wilson et al., 2002) and with the same instrument in minority youth in New York City (Majumdar et al., 2013). Other research demonstrates that dietary behavioral additions may be easier to implement than dietary behavioral subtractions and may have also contributed to the findings revealed in this study (Verplanken & Faes, 1999).

Psychosocial Mediators and HPF

A ceiling effect was seen for negative outcome expectations associated with HPF demonstrating that participants had a high relative understanding of the connection between diet and disease at baseline. Negative outcome expectations are beliefs about the aversive physical outcomes that may result from eating HPF, for example, developing cardiovascular disease or diabetes. Most youth do not tend to be preoccupied with these often abstract and indirect future consequences. However, some studies support these findings, showing that minority youth in particular tend to be familiar with the negative outcomes associated with developing diabetes (Bandura, 2004; Mahajerin, Fras, Vanhecke, & Ledesma, 2008).

Findings from the in-depth interviews triangulate those collected quantitatively by demonstrating that many participants have personal experiences with diet-related diseases, having ill family members and observing them managing or failing to manage diabetes and other health complications.

Activities from the IDOF curriculum that focused on diabetes, and in particular trigger films (short educational clips used to elicit emotion) presenting minority community members struggling with inequality as it relates to health, were particularly salient to participants. Elements of this research suggest that messages surrounding diet-related diseases may resonate when community representation is an essential feature of the message. For instance, when messages include relatable reflections of race and class experiences. Other research supportive of these findings suggests that adolescents are more likely to personalize health-related messages if they believe that there are similarities between themselves and the program messaging (Cuijpers, 2002; Stephenson et al., 2004). Furthermore, other researchers (Necheles et al., 2007; Vangeepuram, Carmona, Arniella, Horowitz, & Burnet, 2015) have demonstrated that urban minority youth are viewing health differences through an equity lens and feel that large community-based advocacy initiatives and changes to their neighborhood “foodscapes” are necessary to support dietary changes.

Last, this research highlights some of the difficulties that participants express in making dietary changes. Although participants discussed the application of both critical thinking skills and self-regulation skills to help them decrease HPF intake, these may not be enough to compete with the realities of their physical and social environments—which are often inundated with highly processed foods.

Psychosocial Mediators and FV

Positive outcome expectations and self-efficacy significantly increased from pretest to posttest. Previous literature indicates that these mediators are typically associated (directly and indirectly) with changes in FV intake. For example, self-efficacy has been shown to be a strong behavioral predictor for FV intake in school-based health education with adolescents (Bruening, Kubik, Kenyon, Davey, & Story, 2010; McClain, Chappuis, Nguyen-Rodriguez, Yaroch, & Spruijt-Metz, 2009; Pearson, Ball, & Crawford, 2011).

General Psychosocial Mediators

Although the survey instrument applied in this study was tested for validity and reliability, there is a methodological concern and potential for measurement error associated with the three-item scale measuring self-regulation skills. Self-regulation skills are complex and may not have been captured adequately in the three-item scale used and may need a more robust scale then applied here.

While mean scores for self-regulation skills did not quantitatively shift from pretest to posttest, in-depth interviews and one-on-on assessments demonstrated that participants were applying self-regulation skills toward the target behaviors. For example, youth reported keeping records of their intake of FV versus HPF with the support of their parents, a strategy that has also been identified in the literature to enhance health behavior change (Cullen, Baranowski, & Smith, 2001). They applied reward structures to increase intake of FV (e.g., eating FV throughout the week for an unhealthy reward on Friday) while limiting HPF and self-management strategies, such as actions to decrease portion sizes.

Food Rules

Participants demonstrated self-regulation skills through the operationalization of many of the Food Rules, though some more so than others. This study reveals that more conceptually accessible Food Rules were commonly described as strategies to achieve the target behaviors. For example, “Break the rules once in a while,” “Make water your beverage of choice,” “Eat your colors,” and “Choose smaller plates and cups” were discussed in detail by participants across qualitative assessments. Whereas those that required first a necessary understanding of terms or did not provide easily actionable or concrete meaning, for example, “Avoid products that make health claims” and “If it came from a plant eat. If it was made in a plant, don’t” were not discussed and adopted by participants.

Social psychological research of self-regulation reveals that the adoption of a new goal can be influenced by the level of specificity (e.g., how concrete versus abstract) or their motivational orientation (e.g., approach—“do this actions”—versus avoidance—“don’t do this actions”), which may have influenced why some Food Rules more than others resonated with the participants (Mann, De Ridder, & Fujita, 2013). The thematic focus of a particular actionable Food Rule tied to curricular activities may have driven the common application of these self-regulation strategies and should be considered when developing other health education with youth.

These findings suggest that the IDOF curriculum may be most effective for promoting consumption of FV, rather than decreasing intake of highly processed foods. In addition, in this young age-group, short actionable food rules may support self-regulation and behavior change.

Limitations

These results are constrained by the small sample size and low statistical power, which may contribute to the lack of observed intervention effect for HPF and some of the psychosocial mediators. Also, by studying mean differences, regression to the mean biases may have been introduced. Behavior change is complex and at the time of posttest assessment (only 2 weeks following the completion of the curriculum) may not have actualized. Furthermore, this study is limited by self-reported dietary intake data collection and for which social desirability was not accounted for. However, almost all dietary behavior studies with groups, whether school-aged or adults, use self-reports. Here, comparisons are made pre to post intervention and between groups using the same method so that social desirability and validity issues are minimized. Still, the results need to be interpreted with caution but provide reasonable evidence for scaling up and testing this program within a larger sample.

Implication for Research and Practice

Despite the small sample size, the findings of this study suggest a possible mechanism for change in FV intake (as related to positive outcome expectations and self-efficacy) that could be explored further and more vigorously with a larger sample. It also draws attention to the social and environmental temptations that exist in the food environments of minority youth that should also be addressed in the development of health education programs in order to better support dietary change and to the importance of cultural representation in education materials. This study also contributes to a growing body of literature that demonstrates that minority youth may already be aware of the long-term chronic disease implications of poor dietary choices, as made salient by exposure to family members, friends, and members of their community with chronic diet-related diseases.

The use of thematically focused, conceptually accessible, and actionable “rules” or guidelines may be a promising approach to help students recall and enact self-regulation strategies and warrants further investigation in more controlled settings. While some of these findings are promising, future research is needed to determine whether a causal link can be drawn and whether or not dietary changes persist over a longer period of time.

Difficulties in the recruitment phase (related to a last-minute dropout and low enrollment) is a challenge, echoed by other researchers working in afterschool settings (Singh, Chinapaw, Brug, & Van Mechelen, 2009) and highlights the precarious nature of setting-based research. This challenge may also draw attention to either a low general interest in or capacity for these types of programs in the afterschool context or inclusion criteria for this study that were too strict. Although afterschool programs typically offer their programming as hourly, 1.5-hour, 2-hour programs, we were only able to accommodate those sites that offered 2-hour programming. The final IDOF curriculum was edited to ensure that it the lessons could be divided into either 20, 1-hour lessons, or 10, 2-hour lessons, and these logistical considerations may also be important for other health-focused afterschool curricula.

Footnotes

Acknowledgements

The authors gratefully acknowledge the contributions of Michael Swartz of Kikim Media and Mark Shelly of Sea Studios for their contributions to the original curriculum development on which this outcome evaluation is based.

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Hiershenee B. Luesse

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