Fasting
The ancient intervention rediscovered. Fasting isn't just about not eating—it's a metabolic switch that triggers autophagy, ketosis, and cellular repair. From time- restricted eating to extended fasts, intentional food breaks offer benefits that go far beyond weight loss.
What Happens During Fasting
Insulin Drops
Without food, insulin falls. Body shifts from storage to burning mode. Fat becomes accessible.
Autophagy Activates
Cells clean up damaged proteins and organelles. Recycling at the cellular level. Anti-aging.
Ketone Production
Liver converts fat to ketones. Brain can run on ketones. Provides stable energy.
AMPK Activation
Energy sensor turns on. Promotes fat burning, inhibits fat storage, improves metabolism.
mTOR Inhibition
Growth signaling pauses. Allows repair and cleanup to occur. Balance is key.
Growth Hormone Rises
HGH increases significantly during fasting. Preserves muscle, promotes fat burning.
Types of Fasting
Daily / TRE
- 16:8: 16 hours fasting, 8-hour eating window. Most popular.
- 18:6: Slightly more aggressive. Good for metabolic issues.
- OMAD: One meal a day. ~23:1. Significant autophagy.
- Best for: Daily practice, weight management, insulin sensitivity.
Periodic / Extended
- 24-hour: Dinner to dinner. Once or twice weekly.
- 36-48 hour: Deeper autophagy. Monthly for most people.
- 3-5 day: Significant immune and stem cell effects. Quarterly.
- 5-day FMD: Fasting-mimicking diet. Easier compliance with similar benefits.
Fasting Timeline
0-4 Hours
Fed state. Digesting. Insulin elevated. Body storing nutrients.
4-12 Hours
Post-absorptive. Insulin dropping. Starting to use glycogen stores.
12-24 Hours
Glycogen depleting. Fat burning increasing. Autophagy beginning. Ketones appearing.
24-72 Hours
Deep ketosis. Strong autophagy. GH elevated. Immune reset by 72h.
Cautions & Contraindications
Avoid Fasting
Pregnancy, breastfeeding, eating disorders, type 1 diabetes, severe underweight, children.
Medical Supervision
Type 2 diabetes on meds, heart conditions, adrenal issues, medication use. Adjust meds.
Start Slowly
Begin with 12-14 hours. Extend gradually. Listen to your body. Extended fasts need preparation.