The higher your body fat percentage, the less accurate your smartwatch is at measuring calories burned https://medicalxpress.com/news/2026-09-higher-body-fat-percentage-accurate.html 4 in 10 US adults own a smartwatch. Worldwide 560 million smartwatch wearers Body fat, skin tone, and the accuracy of smartwatch caloric expenditure estimates https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0353261