10
Loading video...
By Rachael O'Connor
Reporter
0
Share
Newsweek is a Trust Project member
See more of our trusted coverage when you search.Prefer Newsweek on Googleto see more of our trusted coverage when you search.
Calorie tracking apps are popular, but may be missing huge parts of a person's daily intake.
That's according to a new study that looked at AI-powered food apps and found that many underestimate calories and fat.
Tracking apps that estimate the nutritional value and calories just from a photograph have grown in popularity, as they offer an easier way to keep track of your meals.
Read More on Health
The AI image recognition identifies the food in the photo, estimates the size of each portion, and compares the estimates with nutrition databases to calculate the calories.
However, new research suggests some apps are giving a much lower estimation of calories and fat than what is actually on the plate.
Researchers from the American Society for Nutrition tested four photo-based food apps, and found that calorie and fat estimated were, on average, about a third too low.
Researcher Aaron Hengist, of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), said that while photo-based calorie apps are popular among people trying to lose weight, "the accuracy of many of these apps has not been thoroughly evaluated."
He added in a statement to Science Daily: "Our study helps address this question by looking at whether these apps can reliably estimate calories."
The research was presented at NUTRITION 2026 and underwent review by a committee of experts, however, has not yet undergone the full peer review process, and as such is currently considered preliminary results.
...
Researchers created meals in a controlled metabolic kitchen, measuring ingredients to the nearest 0.1 gram to give a highly accurate reference point, and collected photographs of 102 meals.
They then submitted the images to four popular apps—MyFitnessPal, Lose It!, Cal AI and Appediet.
All of the apps estimated calorie totals about 250 to 345 calories too low per meal on average, also underestimating fat by approximately 30 grams, researchers say.
The study found that MyFitnessPal and Lose It! were more accurate when analyzing higher-calorie meals than with lower-calorie meals, and all four apps had more consistent estimates for carbohydrates than for other macronutrients.
Hengist said that "by using meals prepared in a tightly controlled metabolic kitchen, we were able to compare the apps' estimates against a precise reference. This kind of direct, high-quality comparison hasn't been available before."
He warned that anyone using these types of apps "should take the results with a pinch of salt," as "what they actually ate is likely higher than what the app shows."
Low-carbohydrate ketogenic diets, which often contain more fat, may be even more difficult for the apps to estimate, further research showed.
Using an additional 200 meals to investigate which factors may influence the apps' accuracy, the researchers now believe that combining the photo-based tools with traditional methods of evaluating food intake and diet quality could make calorie tracking more accurate.
Reference
American Society for Nutrition. "Your AI calorie-tracking app may be off by 345 calories." ScienceDaily. ScienceDaily, 26 July 2026. www.sciencedaily.com/releases/2026/07/260726015237.htm
Is there a health problem that's worrying you? Let us know via health@newsweek.com. We can ask experts for advice, and your story could be featured in Newsweek.
Contact Newsweek editors on this story: Kara Dolman and Emma Lee-Sang
View 0 Comments
Submit Correction
View Editorial & AI Guidelines