Measuring Dietary Change

This page provides an overview of different tools used to measure dietary change. It is taken from a handout for the CSA & Health Care community of practice. Many of the examples focus on changes in fruit and vegetable consumption or preparing more meals from whole ingredients. The links to the tools connected to the excerpts will provide the full dietary change assessment.

Databases with multiple tools:

Examples of common ways to assess diet quality:

Assessment of Program Capacity for Dietary Change:

Measures of individuals’ dietary change are the most commonly used leading indicators for health outcomes in food and health care programs.  


There is one big caveat. These measures are not good leading indicators if your program has a capacity building focus. For example, if your goal is to prepare your region to offer Medically Tailored Meals or other treatment-focused food programs, then the leading indicator of that capacity is access to nutrition services. If your organization’s role in a food and medicine project is a combination of food provision and referral to nutrition services, then a more important thing for you to evaluate might be the success of those referrals — any relevant dietary information can be reported by your partners, who will have their own measurement tools.

Common implementation metrics can also address capacity, through measuring the foods made available and the number of participants that food reached. Mapping partnerships with other nutrition programs, including how your program complements other food access programs (SNAP / 3SVT, WIC, school meals, seniors meals programs) and nutrition education / counseling services can also measure capacity. Health care providers can track connections with specific diet-focused health services, such as Medical Nutrition Therapy or participation in self-management programs.

The Firm Level Metrics used by the GusNIP program evaluations have some capacity examples.

Measuring Levels of Food Security:

The detailed USDA Food Security Screening surveys provide a basic measure of diet quality, and research has linked changes in food security levels to changes in healthy eating patterns. In some ways we could think about these survey tools as an individual-level capacity assessment. While it is good to have more leafy greens in our diet, if leafy greens are the only thing we feel secure in our ability to have for our diet that is not an overall healthy outcome. These surveys may be particularly useful for programs with a short season (summer for example) that hope to support lasting changes over the course of the entire year. In this situation, how the program fits into the overall picture of food access / food security is particularly important. When used well in the appropriate context, these surveys can be more than data collection, they can open up conversations about what other resources participants might require to feel they’ve reached a greater food security. Information about other food resources and systems to help make referrals is at our Outreach Systems page.

The Gretchen Swanson Center for Nutrition has developed measurement modules for bridging from food insecurity to nutrition security to dietary change, by looking at components of availability, utilization, and stability of nutritious foods. The research and related tools are available online. This work was presented as part of a National Institute of Food and Agriculture (NIFA) webinar series on measuring nutrition security.

Measuring Vegetable Consumption:

Whether it’s eating vegetables or any other type of “virtuous” behavior, there are some basic ways of collecting participant data, each of which have their own pitfalls:

  • Keeping a detailed log for a period of time. This method has an obviously high burden on participants and is primarily used when an individual has selected into a program with the intent to closely monitor their own behavior. And even then, it’s a select few who can actually stay diligent about the exercise.

  • Estimating averages across a period of time. “On average, how many servings of vegetables do you eat every day?” - with an example of what a serving is. We tend to be optimistic in our estimates, especially when the person giving us bags of lovingly curated local produce is the one asking. (And the opposite for behaviors we think we should avoid. A common demonstration of the principle is to ask people to estimate the amount of time they spend on their phone or on social media, then use a tracking app to show how much time is actually spent).

  • Asking for a specific, immediate example. “What vegetables did you eat today?” or “How many servings of vegetables did you eat yesterday?” This works with a sample that’s going to be averaged across a big group (and the respondent is clear that it’s for that purpose, no one is looking at their personal response). Some people will be having a non-average day, but it evens out across the group.

If the goal is to reach a certain threshold of vegetable consumption, these questions can be asked once. Changes require a before and after comparison. A fourth option for comparison:

  • Getting a description of baseline vegetable consumption prior to the program, saving those descriptions, then asking participants to reflect on what has changed over the course of the program. This approach is more qualitative with prompting questions (What meals do you eat vegetables with? Do you eat vegetables as snacks? Do you have favorite recipes that involve vegetables and how often do you prepare them? Can you think of a dish where you enjoyed vegetables with breakfast?). While these responses can be difficult to turn into quantitative data, pulling out a fuller picture of vegetables in participants’ daily diet can give important insights to program development and be used to make more structured tools in future years.

Reviewing the Community Health data sources for Vermont or talking to other community partners about their methods, and matching up the standardized tools they use, can let program evaluation results be placed in a broader community context.

Tools to Measure Changes in Vegetable Consumption:

The SNAP-Ed toolkit provides links to different types of survey tools for measuring food consumption, including changes in consumption patterns and whether participants reach CDC-recommended levels of consumption. The CDC also collaborates on the Have a Plant website to provide consumer information on calculating recommended servings of fruits and vegetables, and understanding what a “serving” means. Many short form validated dietary screeners do not rely on serving size measures, as overviewed in the NIH resource library.

The Townsend Lab at UC-Davis provides food behavior checklists , including a visually enhanced option with screener instructions and a short form Fruit and Vegetable Inventory. Sample questions from the fruit and vegetable inventory:

  • "I feel that I can eat fruit or vegetables as snacks.” | Agree / Middle / Disagree 

  • "I feel that I can plan meals with more vegetables during the next week.” | Agree / Middle / Disagree 

  • “I can add extra vegetables when cooking dishes like casseroles, stews, or grains.” | Agree / Middle / Disagree

These inventories can also feature questions about types of vegetables, such as these survey questions from EFNEP:

  • Over the last week, how many days did you eat dark green leafy vegetables? Examples include kale, spinach, broccoli. 

  • Over the last week, how many days did you eat red or orange vegetables? Examples include tomatoes, carrots, sweet potatoes

Or questions by behavior change or intention: 

  • “After this program I am more interested in trying new types of vegetables” Strongly agree / Agree / Neutral / Disagree / Strongly Disagree.

  • “I will continue eating some of the new foods I tried during this program, when they are available” Strongly agree / Agree / Neutral / Disagree / Strongly Disagree.

Measuring Meals Made from Whole Ingredients:

Behavior checklist style questions from the extended EFNEP survey include:

  • How many days a week do you cook dinner (your main meal) at home? Rarely / 1 / 2 / 3 / 4 / 5 / 6-7 

    • Although not on the EFNEP survey, anecdotally breakfast may be equally important to ask about.

  • How often do you plan your meals before you shop for groceries? Never \ Rarely (about 20% of the time) \ Sometimes (about 40% of the time) \ Often (about 60% of the time) \ Usually (about 80% of the time) \ Always

Some surveys also might measure the frequency of eating the least-healthy processed food options alongside (hopefully) increases in choosing homemade alternatives. For example, from the Mediterranean Diet Assessment:

  • How many times per week do you consume commercial sweets or pastries (not homemade), such as cakes, cookies, biscuits, or custard? (Goal is <3)

Another option is to ask questions specific to how items provided by the CSA share are used. The following are modified from the ACoRN CSA Survey: 

  • Amount of produce you used during the week | All / Between half and all / About one half / Less than ⅓ 

  • What usually happened to the produce you didn’t use | Gave it to someone else / Had to throw it away / Composted / Preserved (frozen, canned, dehydrated) / Other  

Measuring Engagement in Lifestyle-Based Health Changes:

Self-rated health questions often appear on population health studies, including the National Health and Nutrition Examination Survey (NHANES):

  • Would you say that in general your health is excellent, very good, good, fair, or poor?

  • Would you say that in general your diet is excellent, very good, good, fair, or poor?

From the Lifestyle Medicine “Whole Health” survey 

  • On a scale of 1 (low) to 5 (high) please rate both where you are now and where you would like to be for: 

    • Eating healthy, balanced meals with plenty of fruits and vegetables each day.

    • Managing cravings & eating healthy snacks. 

    • Drinking enough water and limiting sodas, sweetened drinks, and alcohol.

From SNAP-Ed : 

“Are you interested in changing your eating behaviors [Insert specific Healthy Eating behavior]?”

“Are you thinking about changing your eating behaviors [Insert behavior]?”

“Are you ready to change your eating behaviors [Insert behavior]?”

“Are you in the process of changing your eating behaviors [Insert behavior]?”

“Are you trying to maintain changes in your eating behaviors [Insert behavior]?”

Yes, I have been for MORE than 6 months.

Yes, I have been for LESS than 6 months.

No, but I intend to in the next 30 days.

No, but I intend to in the next 6 months.

No, and I do NOT intend to in the next 6 months.

See also the Evaluation Models page for examples of dietary change measures used alongside other evaluation elements.