Schedules · Gentle start · 11 h window
13-hour · Circadian
An early dinner and a normal night’s sleep. Most of it is time you were asleep for, which is why people often begin here.
One example day
Eat between 09:00 and 20:00, then fast 13 hours until 09:00 the next day. Any window that fits your day works the same way.
The phases a 13-hour fast reaches
- 0 hBlood sugar settlesDigestion finishes; most notice nothing
- 4 hStored glucose declinesHunger comes in waves
- 8 hFat burningMore fuel drawn from stored fat
The fast ends in fat burning. What happens at 13 hours
13-hour · Circadian is one of the app’s presets. Set it as a routine with a reminder before each fast.