Intermittent Fasting Schedules UK: Choose Your Window
In this guide:
Compare fasting schedules
How to choose your window
Fuel workouts while fasting
Refeed and hydration tips
Mistakes to avoid
FAQ
Compare fasting schedules
| Schedule | Fasting Window | Best For | Watch Outs |
|---|---|---|---|
| 16:8 | 16 hours fast, 8-hour eating window | Beginners, steady fat loss, consistent workdays | Front-load protein; avoid snacking through the whole window |
| 18:6 | 18 hours fast, 6-hour eating window | Breaking plateaus, skipping breakfast | Electrolytes matter more; plan two protein-heavy meals |
| 5:2 | 5 normal days, 2 low-cal days (500–600 kcal) | Flexibility for social events | Low-cal days still need protein and micronutrients |
| Alternate Day | 36-hour fast, 12-hour eat | Advanced users, supervised metabolic resets | Under-recovery risk; only with medical clearance |
How to choose your window
- Match your routine: Pick a window you can keep 5+ days a week; consistency beats intensity.
- Chronotype: Morning trainers often do better with earlier windows (10–6); late trainers with 1–7.
- Health status: If you have diabetes, are pregnant, or have low BMI, talk to a clinician first.
- Ramp gradually: Start 12:12 for a week, then 14:10, then 16:8.
Fuel workouts while fasting
Training fasted is fine for easy cardio. For lifting or HIIT:
- Place your eating window around training when possible.
- Post-workout: 20–40 g protein and 20–60 g carbs to recover.
- Use electrolytes (sodium, potassium, magnesium) on 18:6 or longer windows.
Refeed and hydration tips
- Break the fast with protein + fibre + healthy fats to avoid spikes.
- Drink 2–3 L water daily; add electrolytes on longer fasts.
- Include micronutrient-dense foods: oily fish (omega-3), leafy greens (magnesium), eggs (B12/choline).
- Prioritise sleep (7–9 hours); poor sleep increases hunger hormones.
Mistakes to avoid
- Too little protein (aim 1.6–2.2 g/kg when cutting).
- Relying only on coffee without electrolytes—causes headaches.
- Jumping to extreme windows; leads to binges and drop-off.
- Skipping resistance training—muscle protects metabolism.
FAQ
Can I drink coffee while fasting?
Yes—black coffee or plain tea is fine. Avoid sugar; electrolytes in water are OK.
Do women need a different approach?
Many do better with 14:10 or 16:8 and avoiding long fasts around the late luteal phase. Track energy, sleep, and cycle changes.
How do I track progress?
Combine weight, waist, training performance, sleep, and energy. NutraSafe lets you log fasting windows and see trends.
Start a sustainable fasting plan with balanced nutrition. Download NutraSafe to schedule windows, log meals, and monitor recovery.