The real difference
| 14:10 | 16:8 | |
|---|---|---|
| Example window | 09:00–19:00 | 11:00–19:00 or 12:00–20:00 |
| Breakfast | Usually possible | Usually skipped |
| Meals | Three meals possible | Usually two |
| First challenge | Cutting late snacks | Morning hunger |
If you currently eat from 7 am to 11 pm (16 hours), 14:10 alone cuts your eating span by six hours. The starting point is your current eating span, not a number.
What trials found
- A 12-week trial of an 8-hour window alone found no significant difference in weight loss versus control (TREAT, 2020).
- In a one-year trial where both groups cut calories, adding an 8-hour window did not make a statistically clear difference (2022).
- A 10-hour window study in shift-working firefighters reported good feasibility and some metabolic improvements (2022).
Evidence that you must pass 16 hours to see benefits is weak. Johns Hopkins Medicine notes it can take two to four weeks for the body to get used to intermittent fasting, so the best window is one you can hold for those first weeks.
Stepping up gradually
- Weeks 1–2 — 12:12. Just cut late-night snacks.
- Weeks 3–4 — 14:10. Finish dinner an hour earlier or push breakfast an hour later.
- After that — 16:8 a few days a week if you like. It does not have to be daily.
18:6 and 20:4 are options, not the next level. The shorter the window, the harder it is to fit enough protein and nutrients into the day.
Logging 14:10 in the app
Start 16:8 and stop at 14 hours
The app has four presets: 16:8, 18:6, 20:4 and 24h. For 14:10, start 16:8 and tap "Stop Fasting" after 14 hours. There is no goal notification, so set a phone alarm if you need one.
Change the target to 14 to clear "Under Goal"
Left as is, the record shows "Under Goal" against 16 hours. In History, tap the pencil and set "Target duration (hours)" to 14. It then counts as reached and shows as "14h" in the preset breakdown.
Check the mix in Stats
After a few weeks, the Stats preset breakdown shows how you mixed 14h and 16:8.
FAQ
Is 14:10 really intermittent fasting?
It is a form of time-restricted eating, setting a daily eating window. Consistency matters more than the label.
Skip breakfast or finish dinner early: which 16:8 is better?
Some small studies favour earlier eating for metabolic markers, but nothing is settled. Pick the version that fits your routine.
Sources: Lowe et al., JAMA Intern Med 2020 (TREAT) · Liu et al., N Engl J Med 2022 · Manoogian et al., Cell Metab 2022 (firefighters, 10-hour eating) · Johns Hopkins Medicine, Intermittent Fasting
Intermittent Fasting Timer: 16:8 Diet & Fasting Log
No sign-up, works offline, and your fasting log stays on your phone. Free on Android, in English and Korean.