Intermittent Fasting
Five protocols, real-time metabolic state tracking, AI-guided recommendations, and seamless nutrition integration. Fast smarter, not harder.
Why you'll love it
One-tap fasting timer
Start a fast instantly. A clear countdown shows your remaining time, elapsed hours, and how far through your fasting window you are, glanceable at any moment.
Five fasting protocols
Choose from 16:8, 18:6, 20:4, OMAD (One Meal A Day), or configure a fully custom eating and fasting window. Ascend adapts to your lifestyle, not the other way around.
Real-time fasting state
Track exactly where you are metabolically across six stages: Fed, Early Fasting, Fat Burning, Ketosis, Autophagy, and Deep Ketosis. Know what’s happening inside your body at every moment of your fast.
AI-guided recommendations
Your AI Coach considers your fasting history, training schedule, and nutrition data to suggest the right protocol and optimal eating windows for your specific goals.
Fasting history and streaks
Track consistency with streaks, total fasts completed, average duration, and completion rate. Long-term patterns reveal what works best for your body.
Nutrition tracking integration
Fasting syncs with Ascend’s nutrition dashboard. Your eating window meals count toward your daily calorie and macro targets. The full picture, in one place.
Smart fasting notifications
Get notified when your eating window opens, when you’re approaching the end of your fast, and when you’ve hit a new fasting milestone. Stay on track without watching a clock.
Safety-first design
Built-in safety guidance for extended fasts and warnings for vulnerable groups. Ascend promotes sustainable fasting habits grounded in NHS-backed health information.
Key capabilities
Know where you are, always
Ascend tracks your metabolic state in real time across all five stages of a fast. No guesswork, just a clear indicator of exactly what your body is doing.
Fed
0 – 3 hrsYour body is digesting and absorbing nutrients. Insulin is elevated. Fat burning is minimal. Your cells are running on glucose from the meal.
Early Fasting
3 – 8 hrsBlood glucose begins to fall. Glycogen stores in the liver are still available. Your body is transitioning away from glucose as its primary fuel source.
Fat Burning
8 – 16 hrsGlycogen stores are depleted. Insulin levels are low. Your body is now mobilising stored fat for energy. This is the core benefit of intermittent fasting.
Ketosis
16 – 24 hrsThe liver begins converting fatty acids into ketone bodies. The brain and muscles switch to ketones as their primary fuel. Mental clarity often improves.
Autophagy
24 – 48 hrsYour cells begin recycling damaged components and clearing out dysfunctional proteins. This cellular clean-up process is one of the most researched benefits of extended fasting. Inflammation drops and cellular repair accelerates.
Deep Ketosis
48+ hrsKetone production is at its peak. Autophagy is significantly elevated. Growth hormone levels increase to preserve muscle mass. Extended fasting at this stage requires careful preparation and monitoring.
Supported protocols
16:8
16 hrs fasting · 8 hrs eating
The most popular protocol. Skip breakfast, eat between noon and 8 pm. Easy to maintain long-term.
18:6
18 hrs fasting · 6 hrs eating
A step up from 16:8. Extends fat burning time and pushes further into ketosis. Suits those who have adapted to 16:8.
20:4
20 hrs fasting · 4 hrs eating
Known as the Warrior Diet. One to two meals in a tight 4-hour window. Significant metabolic benefits but requires discipline.
OMAD
23 hrs fasting · 1 hr eating
One Meal A Day. The most aggressive common protocol. Maximum daily ketosis and autophagy. Not recommended without experience.
Custom
Your own eating window
Set any fasting and eating window that fits your schedule and goals. Full flexibility to build a protocol around your life.
Fasting + Nutrition: a complete picture
Fasting and nutrition work together in Ascend. Your eating window meals are automatically tracked against your daily calorie and macro targets, so there's no need to switch between apps or calculate manually. The moment your eating window opens, your nutrition dashboard activates. Your AI Coach also factors your fasting schedule into meal plan generation. If you're running a 16:8 protocol, your meal plan will be structured around your eating window, not a default three-meal day, so your nutrition and fasting goals always align.
Official NHS health guidance
NHS: Intermittent fasting and weight loss →Ready to start?
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