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SNaX for Everyone

A Promising PRC Program HelpsSchools and Communities Promote Healthy Eating and Physical Activity

June 2011

A mural at Vista Middle School in Van Nuys, California

Mealtime Messages
A mural at Vista Middle School in Van Nuys, California, reminds students about good eating habits. The mural caption reads, “Vista…Where students make healthy choices.

What makes bananas a nutritious snack?

“Potassium!” yell students at Vista Middle School in Van Nuys, a suburb of Los Angeles, California.

The students demonstrate their knowledge of nutrition, exercise, and healthy habits after participating in a 5-week program called Students for Nutrition and Exercise (SNaX), which encourages eating well and getting daily physical activity—habits that can help people maintain good health and a healthy body weight.

At Vista, most students qualify for subsidized school lunch because of modest family income, and most of the 1,700 students eat foods from the school cafeteria and campus stores. SNaX takes a multifaceted approach to creating a school environment that makes lunchtime a great time to promote good health. To achieve this environment, the entire community works together. Parents, faculty, and administrators become involved and encourage students to choose healthy lunch options instead of fast food and snacks. The cafeteria staff prepares nutritious and appealing meals within the budget, personnel resources, and kitchen equipment.

Since 1980, obesity and overweight have more than tripled in children and adolescents and can raise their risk of diabetes, heart disease, and other serious health conditions.

“The SNaX program is about helping inter-related pieces of a puzzle fit together,” said study coordinator Burt Cowgill, PhD. Dr. Cowgill is part of the UCLA/RAND Center for Adolescent Health Promotion, a Prevention Research Center (PRC) that partners with the Los Angeles Unified School District and other researchers in developing and evaluating SNaX.

“To be successful,” Dr. Cowgill added, “a school-based child obesity program must teach students why good nutrition is important to their health, support schools in providing healthy foods, and use strategies that encourage kids to eat well.”

Jacinta Elijah from the UCLA/Rand PRC

Coaching Young Counselors
Jacinta Elijah from the UCLA/RAND PRC gives peer leaders a last-minute pep talk before sending them out to speak with their classmates.

First Period: SNaX Seems Successful

In a SNaX pilot test, about 140 seventh graders at a middle school in Los Angeles learned about healthy eating, how to be peer leaders, and how to teach their classmates about healthy habits. Surveys and daily food-use information recorded by cafeteria staff suggested that students in a comparison school not receiving SNaX showed declining interest in healthy foods during a 5-week period. In contrast, the SNaX peer leaders in the program school drank fewer sugar-sweetened drinks (a decrease from 33% to 21%) and increased consumption of healthy foods, such as cut fruit, yogurt parfaits, and salads. The researchers were determining the feasibility of conducting a large evaluation to assess the program’s effectiveness, but school district officials found the pilot study’s implications so compelling that they made $7 million available to provide the fruits found to be popular with students.

“We found that kids like to eat fruit, but if it is not ripe and ready-to-eat, they are likely to throw it away—especially if they have to peel it themselves,” Dr. Cowgill said. “We also learned that we have to try to increase participation in SNaX so that all students get the same level of benefit as the peer leaders. Now we involve as many people as we can in class exercises and homework that invites a student’s entire family to learn about healthy eating and staying active.”

Vanessa Garcia, a research assistant working with the UCLA/Rand Prevention Research

Taste Station
Vanessa Garcia, a research assistant working with the UCLA/RAND PRC offers celery for students to sample and then asks for feedback on a short survey.

SNaX 101

The SNaX interventionthat evolved from the pilot study presents five 1-week programs on the following health themes: healthy beverages, cafeteria options, benefits of a healthy diet, physical activity (PA), and understanding media messages. Each week, about 25 students from a health class are invited to become peer leaders. On Tuesdays, they meet during lunchtime with PRC trainers, and as they play a trivia game together, the students realize many of the messages they get from television and other media about diet and health are inaccurate. They learn that by drinking water after exercise they rehydrate without the sugar found in many sports drinks. Program messages are simple and repeated often so that the peer leaders learn them and pass them on to their classmates and family members.

“Basic concepts help students understand why physical activity is so good for them and how the information on nutrition labels can help them find an energy balance,” said PRC trainer Jacinta Elijah.

We hope the SNaX program will give schools a basic roadmap to help staff, parents, and kids. Then other schools can find answers that work in their communities,” said Paul Chung, MD, the SNaX study principal investigator.

“We also want the students to understand that they can get physical activity in short intervals throughout the day,” said PRC co-trainer Guadalupe Mota. “The recommended amount is 60 minutes each day. We show them that being active 10 minutes at a time, six times a day, works just as well as all at once.”

In the SNaX PA sessions, students learned to limit the amount of time spent in front of computer and television screens and to do push-ups during commercials. On Wednesdays, the peer leaders work on their counseling skills so they can teach classmates about what they learned.

“We may show them how to start a conversation, but when the students see what we suggest, they always chime right in and tell us, ‘Oh, I can do that soooo much better!’ So we sit back and have them show us,” Ms. Elijah said.

Then during lunch, the peer leaders approach their classmates and discuss situations when they can make healthy choices.

A colorful SNaX study banner and physical activity posters overlook an outside lunch area and pavilion.

Encouraging Signs

A colorful SNaX study banner and physical activity posters overlook an outside lunch area and pavilion. Enlarge photo.

Other Forms of Encouragement

As part of the SNaX program, the PRC and its partners worked with a graphic designer to produce school posters that urge students to be active and choose healthy foods at lunchtime. Signs promote menu items of the day and give their calorie counts. The PRC works with the cafeteria staff to call attention to the nutritious foods.

During lunch, SNaX researchers set up a station where students can try foods like celery sticks. The taste-testers fill out a short survey that lets the team—and cafeteria staff—know how well they like the sample foods. During lunchtime, the school offers filtered water for free, and the students fill their SNaX water bottles and drink from them throughout the day. After the pilot study, the school district adopted a policy requiring all its schools to offer free water during lunch.

The SNaX program was a catalyst at our school. If other schools can generate similar levels of participation and excitement, they too should be able to follow the SNaX program,” said Nidia Castro, principal of Vista Middle School in Van Nuys, California.

“But changing school policy is just one step,” said Kimberly Uyeda, MD, MPH, the school district’s director of student medical services and a coresearcher in the SNaX study. “To change behavior, you have to develop best practices and ideas. SNaX is not just about obesity; it’s also about the school system trying to take practical steps toward solutions.”

Nidia Castro, the school’s principal, confirmed the Vista community’s strong support for the SNaX program, which will continue after the study ends. At Vista, parents attended a summit on childhood obesity, and the school received a grant through the Sound Body, Sound Mind Organization to purchase equipment for a school-community fitness center, where students and their families can exercise together.

SNaX is not just about obesity; it’s also about the school system trying to take practical steps toward solutions,” said Kimberly Uyeda, MD, MPH, director of student medical services in the Los Angeles Unified School District and SNaX coresearcher.

Kimberly Uyeda, MD, MPH, SNaX researcher, and Los Angeles Unified School District director of student medical services

Developing Tools for Schools

Kimberly Uyeda, MD, MPH, SNaX researcher, and Los Angeles Unified School District director of student medical services, said if the program is effective, the team could help adapt SNaX materials for use across California and other states.

“The SNaX program was a catalyst at our school,” Ms. Castro said. “If other schools can generate similar levels of participation and excitement, they too should be able to follow the SNaX program.”

Next Steps

The main measure of SNaX’s success will be cafeteria information that shows whether students are choosing healthy foods more often than those high in sugar, fat, and salt. The researchers analyze the daily cafeteria records of what was served and what students took to eat.

“Then we know we are seeing the changes in behavior the SNaX program tries to promote,” said Paul Chung, MD, principal investigator for the study. “These changes need to happen before we can see improvements in weight.”

In the next stage of SNaX, Dr. Chung, Dr. Cowgill, and their colleagues will increase family participation in the program, to help communities promote healthy eating and active lifestyles. The center has conducted focus groups with parents—in Spanish and English—to get their input on training parents to be peer leaders for their friends and neighbors. Then families will have strategies to follow at home that reinforce what the youths learn at school.

“We hope the SNaX program will give schools a basic roadmap to help staff, parents, and kids,” said Dr. Chung. “Then other schools can find answers that work in their communities.”

Group of children

SNaX Pack

These peer leaders at Vista Middle School said they liked participating in the program because it taught them about nutrition and staying healthy.

SNaX Week–to–Week

Week 1: Healthy Beverages
Messages: Water is a healthy drink. Within Vista's school district, soda has been banned from school grounds, but the flavored milk drinks offered have a lot of sugar and extra calories.
Homework: Think what you drink.

Week 2: Cafeteria Options
Message: Tasty, healthy meals are available in the cafeteria.
Homework: Understand healthy fats.

Week 3: Benefits of a Healthy Diet

Message: How food is prepared and how much is consumed can determine its healthiness. Students identify the healthiest food in given groups—for example, select baby carrots, salad with blue cheese dressing, or fried zucchini.
Homework: Know the facts about fruits and vegetables.

Week 4: The Balance of Food Intake and Physical Activity
Messages: Short intervals of exercise work well throughout the day. Moderation with food intake is key to a healthy diet. Pedometers record activity levels.
Homework: Try physical activities such as walking or bicycling with family members.

Week 5: Understanding Media Messages

Messages: Fast-food restaurants and snack food makers want children to buy and eat junk food.
Homework: Count television commercials, look for trends in food messages, and note the advertisers and products. Note the encouragement to overeat or eat snack foods.

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