AI calorie apps underestimate meal calories by 33%

Research presented at the annual NUTRITION meeting found that AI-powered photo-based calorie-tracking apps underestimate meal energy content by about 33%, potentially misleading users about their actual intake. The controlled feeding study analyzed 102 nutrient-controlled meals using four commercial apps—Appediet, Cal AI, Lose It!, and MyFitnessPal—comparing their estimates against precise food composition tables. Each app underestimated calories differently, ranging from 252 to 345 kcal per meal, and all apps underestimated fat content by 30 g. Researcher Aaron Hengist advised users to treat app results cautiously, noting that actual consumption is likely higher than displayed, especially for fats. Future work should evaluate whether photo-based AI can reduce the burden of traditional diet assessment methods.