Can I drink coffee while fasting?

Yes, as long as it is black coffee (no sugar, no milk). Black coffee, plain tea, and water do not trigger an insulin response and therefore do not break your fast.

What is the best fasting window for beginners?

The 16:8 protocol is the most popular starting point. You fast for 16 hours and eat all your meals within an 8-hour window (e.g., 12 PM to 8 PM).

How long does it take for autophagy to start?

Autophagy usually begins after 16-18 hours of fasting and peaks around 48-72 hours. However, even shorter fasts provide significant benefits for insulin sensitivity.

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Fasting Visualizer Calculator

Intermittent Fasting Visualizer

Stay consistent with your fast. Calculate exactly when to break your fast and when to stop eating.

Your Schedule

Start Eating

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Break Fast

Stop Eating

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Start Next Fast

Total Fasting Time

16 Hours

How This Fasting Tool Works

The Intermittent Fasting Visualizer is designed to help you synchronize your internal clock with your nutrition goals. By defining exactly when your "Last Bite" occurred, this tool projects your metabolic transition phases—from the absorptive state to the early stages of fat oxidation (lipolysis).

Core Protocol Logic

16:8 (Leangains): The gold standard for daily maintenance and muscle retention.
18:6 (Moderate): Increases the duration of the 'fat-burning' state by 2 additional hours.
OMAD (One Meal A Day): A 23:1 schedule that maximizes insulin sensitivity and simplifies meal prep.

Example: The 16:8 Workday Sync

If you finish dinner at 8:00 PM (Start Fast):

- Break Fast: 12:00 PM the next day.
- Eating Window: 12:00 PM to 8:00 PM.

This schedule allows you to skip breakfast while having a social lunch and a family dinner, maintaining social flexibility without sacrificing metabolic health.

Architect's Tip: Don't obsess over the exact minute. Intermittent Fasting is about consistency over weeks, not perfection over hours. If you break your fast 30 minutes early one day, just resume your normal schedule the next.

Fasting Intelligence FAQ

Does lemon water break a fast?

Small amounts of lemon juice (less than half a lemon) contain negligible calories and will not break a metabolic fast. It's an excellent way to improve the taste of water during long windows.

Should I work out while fasting?

Yes. Training in a fasted state can accelerate fat loss as your body is forced to use stored energy. However, if you feel lightheaded, prioritize safety and have a small high-protein snack.

What is 'Clean' vs 'Dirty' Fasting?

'Clean' fasting means only water, black coffee, or plain tea. 'Dirty' fasting allows for low-calorie additives like cream or BCAAs. While dirty fasting might help for weight loss, clean fasting is required for maximum autophagy.