10/21/2026
Smartwatch calorie accuracy is not good enough to decide what you eat.
In a July 2026 lab study, four popular watches missed exercise calories by a median of about 15–25%. The miss grew as body fat rose — the people most likely to use a burn number to lose weight were served worst. Heart rate and steps on the same devices are more trustworthy.
Do not eat back the workout total. Build meals from food you can see: vegetables, a palm of protein, fiber. Keep the watch for walking, lifting, and sleep timing.
Physician-reviewed breakdown:
https://medsurfer.com/smartwatch-calorie-accuracy/