Tap the + button near the bottom of the screen
Select “Edit Day”
Under “Day Properties,” tap the “Fasting” tile to toggle
Tap the checkmark to save
Note: You only need to mark a day as fasting if both of these are true:
You didn’t consume any calories for the entire day. So, for instance, if you ate dinner on Monday night, fasted for 24 hours, and then ate dinner on Tuesday night, you don’t need to mark Tuesday as a fasting day. However, if you ate dinner on Monday night, fasted all day Tuesday, and didn’t eat again until Wednesday, you would want to mark Tuesday as a fasting day.
You don’t log any foods or beverages on your fasting days. For example, if you fasted from Monday evening to Wednesday morning, but you still logged any zero-calorie beverages or supplements you consumed on Tuesday, you wouldn’t need to mark Tuesday as a fasting day.