Researchers tested two popular free food tracking apps—MyFitnessPal and Cronometer—to see how accurately they measure what athletes eat. They had people record their meals for three days, then entered that information into both apps and compared the results to a gold-standard nutrition database. MyFitnessPal had problems with accuracy and consistency, especially when different people entered the same meals. Cronometer performed much better overall, giving more reliable and accurate nutrition information. For athletes who need precise nutrition tracking, this research suggests Cronometer might be the better choice.

The Quick Take

  • What they studied: How well two free nutrition apps (MyFitnessPal and Cronometer) accurately track what people eat compared to a trusted nutrition database
  • Who participated: 43 Canadian endurance athletes (people who do sports like running or cycling) - 27 men and 16 women - who recorded everything they ate for three days
  • Key finding: Cronometer was significantly more accurate and consistent than MyFitnessPal. MyFitnessPal had problems tracking calories, carbs, protein, and fiber, while Cronometer got almost everything right except fiber and vitamins A and D
  • What it means for you: If you’re an athlete tracking your nutrition, Cronometer appears to give you more trustworthy information about what you’re actually eating. MyFitnessPal may show numbers that don’t match your real intake, which could affect your training and performance goals

The Research Details

This study was observational, meaning researchers watched and measured what happened without controlling variables. They collected detailed food records from 43 athletes over three days. Two different people independently entered each person’s meals into MyFitnessPal and Cronometer to test if they got the same results. Then, one person entered all the meals into a professional nutrition software (ESHA Food Processor) using Canada’s official food nutrient database as the ’true’ answer. By comparing the app results to this reference standard, researchers could measure how accurate each app was.

The researchers specifically looked at two types of accuracy: reliability (whether different people get the same answer when using the same app) and validity (whether the app’s answer matches the true nutritional content). They also looked for differences between men and women to see if the apps worked differently for each group.

Athletes have very specific nutrition needs—they need to know exactly how many calories, carbs, and proteins they’re eating to fuel their training properly. If an app gives wrong numbers, athletes might eat too much or too little, which could hurt their performance and recovery. Testing these apps against a trusted standard helps athletes know which tool they can rely on.

This study is reliable because it used a gold-standard reference database (Canada’s official nutrient file) to check accuracy. Having two different people enter data into each app tested whether the apps were consistent. The study included both men and women, allowing researchers to spot gender differences. However, the sample size of 43 athletes is relatively small, and the study only included Canadian athletes, so results might differ in other countries or populations.

What the Results Show

MyFitnessPal showed significant problems with accuracy. When measuring total calories, carbohydrates, protein, cholesterol, sugar, and fiber, the app’s numbers didn’t match the true nutritional content. The problems were especially bad for calories, carbs, and sugar—and these errors were mostly driven by women’s data. Protein errors were mainly from men’s data. Additionally, MyFitnessPal wasn’t consistent between raters: when two different people entered the same meals, they got different results for sodium and sugar, particularly among men.

Cronometer performed much better. It showed good to excellent consistency when different people entered the same meals, and it accurately measured almost all nutrients. The only nutrients where Cronometer struggled were fiber and vitamins A and D. Importantly, Cronometer worked equally well for both men and women, with no significant gender differences.

Why the difference? MyFitnessPal has thousands of food options in its database, including entries added by regular users that aren’t verified by experts. This creates confusion and inconsistency. Cronometer’s database appears to be more carefully maintained. The gender differences in MyFitnessPal might be because women typically record more detailed descriptions of what they eat, which can lead to different interpretations when entering data.

Women and men showed different patterns with MyFitnessPal. Women’s data had more errors in calorie, carb, and sugar tracking, while men’s data had more protein errors. This suggests the app may struggle differently depending on typical eating patterns. For Cronometer, these gender differences didn’t appear, suggesting it handles diverse eating patterns more consistently. The fiber tracking issues in Cronometer may stem from how the software categorizes fiber (total versus soluble), and vitamin A and D problems likely relate to different fortification practices across brands and countries.

This is one of the first studies to directly compare these two popular apps using a rigorous scientific method with a trusted reference standard. Previous research has questioned the accuracy of food tracking apps generally, but this study provides specific evidence about which app performs better for athletes. The findings align with concerns that user-generated databases (like MyFitnessPal’s) can be less reliable than professionally-maintained ones.

The study only included 43 athletes from Canada, so results may not apply to athletes in other countries or non-athletes. The sample size is relatively small, which means some findings might change with a larger group. The study only looked at three-day food records, so it doesn’t show how the apps perform over longer periods. Additionally, app updates and database changes happen frequently, so the accuracy of these apps may change over time.

The Bottom Line

For athletes who need accurate nutrition tracking: Cronometer appears to be the more reliable choice (strong evidence). MyFitnessPal may provide misleading information about calories, carbs, and protein intake (moderate evidence). If you use MyFitnessPal, be aware that the numbers may not reflect your actual intake. Consider double-checking important nutrients with a sports dietitian or using Cronometer instead.

This matters most for competitive endurance athletes (runners, cyclists, triathletes) who carefully manage their nutrition for performance. It’s also relevant for anyone trying to track specific nutrients precisely. People doing casual fitness tracking may not need this level of accuracy. If you’re using an app just to get a general sense of your eating habits, either app might work fine.

You should notice differences in the numbers immediately when comparing the apps with the same meals. However, the real impact on your training and performance would take weeks to months to observe, depending on how much the inaccurate tracking affects your actual eating decisions.

Want to Apply This Research?

  • If using a nutrition tracking app, record your daily calorie, carbohydrate, and protein intake for one week in your chosen app, then verify 2-3 days of meals against a sports dietitian’s assessment or a second app (like Cronometer) to check for accuracy patterns specific to your eating style
  • Switch to Cronometer for nutrition tracking, or if you prefer MyFitnessPal’s interface, manually verify your calorie and macronutrient totals weekly by photographing meals and having them reviewed by a nutrition professional to catch potential tracking errors
  • Track not just the app’s reported numbers, but also your actual athletic performance metrics (energy levels, recovery time, workout quality) monthly to see if your nutrition tracking accuracy correlates with real-world results; adjust your app choice if performance suffers despite following the app’s recommendations

This research compares the accuracy of two nutrition apps but does not provide medical or dietary advice. Individual nutritional needs vary based on sport, training intensity, body composition, and health status. Athletes should consult with a registered sports dietitian or nutritionist before making significant changes to their nutrition tracking methods or dietary intake. App accuracy is just one factor in effective sports nutrition—professional guidance is essential for optimizing athletic performance and health. The findings reflect the apps’ performance at the time of study; app features and databases change frequently.