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Intermittent Fasting Timer

Choose your fasting window (16:8, 18:6, OMAD) and visualize your progress alongside the physiological metabolic stages of fasting.

Fasting Protocol Settings
Choose your fasting schedule and specify your fast start time.

16 hours fast, 8 hours eating window. The most popular method.

Simulate Fast Elapsed Time
Metabolic Autophagy Timeline
Understand how your metabolism shifts at different stages of your fast.

Digestive Phase

0-4h

Blood sugar rises, body processes food, insulin spikes.

Fat Burning Begins

4-12h

Insulin levels drop, blood sugar returns to normal, fat cells start releasing energy.

Ketosis & Peak Fat Burn

12-16h

Glycogen depletion triggers ketone body production. Fat burn reaches peak rate.

Autophagy Phase

16-24h

Autophagy (cellular cleaning & recycling) accelerates as cells discard damaged components.

Deep Cellular Reset

24-48h

Deep autophagy clears cellular junk, and immune cell regeneration starts.

Fasting Dashboard
Fasting window goal is 16 hours.

Elapsed Fasting Time

0h 0m 0s

0% of 16h goal

Active Metabolic State

Digestive Phase

Blood sugar rises, body processes food, insulin spikes.

Understanding Intermittent Fasting & Metabolism

Intermittent fasting (IF) is not a diet, but an eating pattern that cycles between periods of eating and fasting. Instead of changing what you eat, it changes when you eat. By extending the natural overnight fast, you allow your body to exhaust its glycogen stores and transition into a unique physiological state dominated by cellular cleanup and fat-oxidation.

The Stages of the Fasting Metabolic Timeline

When you stop consuming calories, your body moves through distinct metabolic checkpoints:

  1. The Fed State (0 to 4 hours): Your body digests the meal. Blood sugar rises and insulin is secreted to transport glucose into cells for immediate energy or glycogen storage.
  2. The Early Fasting State (4 to 12 hours): As digestion finishes, blood glucose levels return to baseline. Insulin levels drop, signaling the liver to begin breaking down glycogen stores and fat cells to release fatty acids.
  3. Ketosis (12 to 16 hours): Glycogen reserves become depleted. The liver starts converting fatty acids into ketone bodies, which serve as an alternative, highly efficient energy source for the brain.
  4. Autophagy (16 to 24 hours): As insulin remains low, cells trigger autophagy. In this state, cells degrade and recycle old, damaged organelles and misfolded proteins, promoting cellular rejuvenation.
  5. Deep Autophagy & Reset (24+ hours): Prolonged fasting further reduces inflammation, stimulates growth hormone secretion, and triggers stem-cell-based renewal of the immune system.

How to Succeed with Intermittent Fasting

  • Stay Hydrated: Drink plenty of water. Plain sparkling water, black coffee, and green tea are excellent for suppressing hunger during the fasting window.
  • Electrolytes: If fasting for 18+ hours, consider adding a pinch of high-quality salt or sugar-free electrolyte powder to your water to prevent headaches or muscle cramps.
  • Break Your Fast Gently: Focus on protein and healthy fats (like eggs, chicken, or avocado) when ending your fast. Avoid massive carb-loaded meals, which can lead to a severe insulin spike and lethargy.

Frequently Asked Questions