AI-powered calorie tracking apps can estimate a meal's nutritional content from a single photograph. The technology offers a fast and convenient alternative to manually entering every food and portion, but new research suggests the results may be considerably lower than what is actually on the plate.
In a test of four photo-based apps, researchers found that calorie and fat estimates were about one-third too low on average.
How AI Estimates Calories From Food Photos
"Photo-based calorie tracking apps are very popular, especially for people trying to manage their health or lose weight," said Aaron Hengist, a postdoctoral visiting fellow with the Intramural Program of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. "However, the accuracy of many of these apps has not been thoroughly evaluated. Our study helps address this question by looking at whether these apps can reliably estimate calories."
Olivia Charles, a postbaccalaureate intramural research training fellow at NIDDK, presented the findings at NUTRITION 2026, the flagship annual meeting of the American Society for Nutrition, held July 25-28 in National Harbor, Maryland, just outside Washington, D.C.
