§ · Fasting
16:8. 18:6.20:4. OMAD.
Built-in fasting timers, milestones, and streak protection. Same app as your nutrition log — fewer apps to juggle.
§ 01 · The protocols
Four named protocols plus custom durations from one to seventy-two hours. Pick by what fits the rest of your day, not by what looks the most aggressive on paper.
16:8 · 16h fast / 8h feeding
e.g. eat 12pm–8pm. The entry protocol. Skips breakfast or dinner. Most people land here when they're sustainable.
18:6 · 18h fast / 6h feeding
e.g. eat 1pm–7pm. For people who already skip breakfast and want a slightly tighter window.
20:4 · 20h fast / 4h feeding
e.g. eat 4pm–8pm. Closer to OMAD. Two meals or one meal plus a snack inside a 4-hour window.
OMAD · 23h fast / ~1h feeding
one meal a day. One meal a day. The aggressive protocol — not where most people start, and not for everyone.
§ 02 · Milestones
Four milestone notifications fire during a fast — useful landmarks, not gimmicks.
12 hours
Glycogen drawdown is meaningfully underway. Most people feel the shift here.
16 hours
The 16:8 finish line. If you stop here, the fast counts under that protocol.
18 hours
The 18:6 finish line. Slightly past the obvious break.
24 hours
A full-day fast. Beyond is custom territory.
§ 03 · Streak protection
BiteDeck's daily streak tracks days you logged something. That used to be a problem on fast days — if you skipped meals entirely, the streak broke even though you were doing exactly what your plan said.
The fix: completed fasts of 20 hours or more automatically protect their end-day as a logged day. You can run an OMAD or a 24-hour fast and keep your streak intact without forcing a placeholder log. The protection applies to whichever calendar day the fast ended.
This isn't a separate fasting app talking past your nutrition app. The fast and the streak know about each other.
§ 04 · Fasting + nutrition tracking, in one app
The case for combining: fasting changes your effective deficit math (your eating window collapses, intake compresses, the body of the day looks different on the macro chart). A dedicated fasting app doesn't see that side. A pure calorie tracker doesn't see the fast.
BiteDeck's weight forecast uses your actual logged intake against maintenance TDEE — no special-cased fasting branch needed, because the data lives in one place.
§ 05 · Custom durations
The four named protocols are starting points. Custom mode accepts any duration from one to seventy-two hours. Useful for:
- Extended fasts up to three days (with appropriate caution).
- One-off skipped meals that don't fit a named protocol.
- Religious observance windows.
- Pre-procedure fasting where the duration is dictated.
The 20-hour streak-protection rule applies to custom fasts the same way it applies to OMAD.