According to Gram Research analysis of a 12-month study with 699 participants, how well a mobile produce market program is actually run directly affects whether people eat more fruits and vegetables. Sites that followed the Veggie Van program instructions more carefully saw significantly larger increases in fruit and vegetable consumption, with nutrition education being the strongest predictor of dietary improvement.
A Gram Research analysis of a mobile farmers market program called the Veggie Van found that how well the program is actually run matters a lot for helping people eat more fruits and vegetables. Researchers studied 699 people across 17 different mobile market locations and discovered that sites that followed the program’s instructions more carefully saw bigger improvements in what people ate. The strongest results came from sites that did a better job teaching people about nutrition. This research shows that even great ideas need to be executed well to make a real difference in people’s health, especially in communities that don’t have easy access to fresh produce.
Key Statistics
A secondary analysis of a randomized controlled trial with 699 participants across 17 mobile market sites found that higher implementation fidelity of the Veggie Van program was positively associated with greater increases in fruit and vegetable consumption over 12 months (correlation coefficient of 0.56, p=0.02).
In the same 2026 study of the Veggie Van intervention, sites that implemented nutrition education components with greater fidelity showed a particularly strong association with improved fruit and vegetable consumption (correlation coefficient of 0.81, p<0.001).
The Veggie Van study found that across 17 mobile market sites, the average implementation fidelity score was 40.6 out of 55 possible points, indicating that most sites had room for improvement in following the program model.
Research from the Veggie Van process evaluation showed that implementation fidelity improvements were associated with better dietary outcomes in lower-income communities, suggesting that how well programs are executed matters as much as the program design itself.
The Quick Take
- What they studied: Whether following the Veggie Van program instructions carefully actually leads to better results in helping people eat more fruits and vegetables
- Who participated: 699 people from lower-income communities across 17 mobile produce market locations in multiple states who participated in the Veggie Van program for 12 months
- Key finding: Sites that followed the program’s core instructions more closely saw fruit and vegetable consumption increase by larger amounts. Nutrition education was the most important part—sites that taught people about healthy eating saw the strongest improvements.
- What it means for you: If you’re involved in a community health program, doing things the right way really matters. For people in underserved areas, the Veggie Van works best when the program is run with care and includes good nutrition education. Results may vary depending on how well your local program follows the model.
The Research Details
This study looked at information already collected from a larger research project that tested the Veggie Van program across multiple states. Researchers had tracked 699 people for 12 months, measuring what they ate using detailed food diaries and surveys, and checking their food security (whether they had enough food to eat). They also collected information about how well each of the 17 mobile market sites actually followed the Veggie Van program’s instructions—things like whether they offered nutrition classes, how often they visited neighborhoods, and what produce they sold.
The researchers then connected the dots: they looked at whether sites that followed the program instructions more carefully had participants who improved their eating habits more. They used statistical methods to see if there was a real connection between how well the program was run and how much people’s diets improved.
Understanding whether a program works is important, but understanding how it works and when it works best is even more valuable. This research approach, called a process evaluation, helps program leaders figure out which parts of their program are most important and where they should focus their training and support. It’s the difference between knowing a recipe works and knowing which ingredients are most critical to success.
This study has several strengths: it tracked real people over a full year, it included a large number of participants (699) across multiple locations, and it measured actual eating habits using detailed dietary recalls rather than just asking people general questions. The study was based on a randomized controlled trial, which is considered high-quality research. However, this was a secondary analysis, meaning researchers looked at data collected for a different purpose, which can sometimes limit what conclusions can be drawn.
What the Results Show
The main finding was clear: sites that followed the Veggie Van program more carefully saw bigger improvements in how much fruit and vegetables people ate over the 12-month period. On average, sites scored 40.6 out of 55 possible points for following the program correctly. When researchers looked at the connection between these scores and dietary changes, they found a strong relationship (a correlation of 0.56, which is considered moderate to strong in research terms).
Even more striking was what happened with nutrition education—the classes and teaching about healthy eating. Sites that did a better job with nutrition education saw the strongest improvements in what people ate. This part of the program had a very strong connection to dietary improvements (a correlation of 0.81, which is very strong). This suggests that teaching people why they should eat more fruits and vegetables, and how to do it, might be just as important as making the produce available.
The study also looked at food security (whether people had enough food) and how often people actually used the mobile markets. While these outcomes improved overall, the strength of the connection to program fidelity was not as strong as it was for fruit and vegetable consumption.
Beyond the main findings about fruit and vegetable consumption, the research showed that the program did help with food security—people reported having better access to food overall. However, this improvement wasn’t as strongly connected to how well the program was run as the dietary improvements were. The study also found that people who participated in the program used the mobile markets regularly, showing that the Veggie Van successfully attracted customers from the communities it served.
Previous research on the Veggie Van had shown that the program could increase fruit and vegetable consumption in lower-income communities, which was encouraging. However, those earlier studies didn’t look closely at whether some sites were more successful than others or why. This study fills that gap by showing that implementation quality matters significantly. It aligns with broader research showing that community health programs often work better when they’re delivered with high quality and consistency.
This study has some important limitations to keep in mind. First, it was a secondary analysis, meaning researchers used data that was collected for a different purpose, which can limit what they can conclude. Second, the study measured implementation fidelity based on what organizations reported they were doing, not necessarily what was actually happening on the ground. Third, the study couldn’t prove that better implementation caused better results—only that they were connected. Other factors not measured in the study might have influenced both implementation quality and outcomes. Finally, the results come from specific communities and organizations, so they may not apply exactly the same way everywhere.
The Bottom Line
If you’re running or participating in a community produce program like the Veggie Van, prioritize nutrition education and teaching alongside making produce available. Program leaders should focus on training and support to help staff follow the program model consistently. For people in underserved communities, look for programs that combine access to affordable fresh produce with classes or information about how to prepare and eat more fruits and vegetables. Confidence level: Moderate to High—this finding comes from a well-designed study with a large number of participants, though it’s based on one program model.
Community health workers, nonprofit leaders, and public health officials running produce access programs should care most about these findings. People in lower-income neighborhoods who want to eat healthier will benefit from knowing that programs work best when they include education. Policymakers deciding how to fund community health initiatives should understand that implementation quality matters as much as the program idea itself.
Based on this study, people who participated in the Veggie Van program saw improvements in their fruit and vegetable consumption over 12 months. You shouldn’t expect overnight changes—dietary habits take time to shift. If you’re involved in a similar program, plan for at least 6-12 months to see meaningful changes in eating patterns.
Frequently Asked Questions
Does the Veggie Van program actually help people eat more fruits and vegetables?
Yes, but it depends on how well the program is run. A study of 699 participants found that sites following the program carefully saw significantly larger increases in fruit and vegetable consumption over 12 months, especially when nutrition education was included.
What part of the Veggie Van program is most important for changing what people eat?
Nutrition education—teaching people about healthy eating—showed the strongest connection to dietary improvements. Sites that prioritized nutrition classes alongside produce access saw the best results in helping people eat more fruits and vegetables.
How long does it take to see results from a produce access program like the Veggie Van?
The Veggie Van study tracked people for 12 months and found meaningful improvements in fruit and vegetable consumption over that timeframe. Most dietary changes take several months to develop, so patience and consistent participation are important.
Does the Veggie Van help with food security and having enough food to eat?
The program did improve food security overall, but this improvement wasn’t as strongly connected to how well the program was run as the dietary improvements were. The main benefit appears to be increasing access to fresh produce rather than solving broader food security issues.
Can I expect the same results from every Veggie Van location?
Results vary by location depending on how well each site follows the program model. Sites that implement nutrition education and follow program guidelines more consistently see better dietary outcomes, so quality of implementation at your local site matters significantly.
Want to Apply This Research?
- Track daily servings of fruits and vegetables consumed, noting which ones came from the mobile market. Set a goal to increase from baseline by 0.5 servings per day each month.
- Use the app to find when and where the Veggie Van visits your neighborhood, set reminders to visit, and log what produce you buy. Connect this with a nutrition education feature that suggests recipes or preparation tips for items you purchase.
- Monthly check-ins comparing your fruit and vegetable intake to previous months. Track not just quantity but also variety of produce consumed. Connect with nutrition education resources in the app to reinforce learning alongside market visits.
This research describes findings from the Veggie Van program and should not be considered medical advice. Individual results may vary based on local program implementation, personal circumstances, and dietary habits. If you have specific health concerns or dietary needs, consult with a healthcare provider or registered dietitian. This study was conducted with specific populations and communities; results may not apply identically in all settings. The research shows associations between program implementation quality and outcomes, but does not prove that better implementation directly causes better results.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.