Water fasting involves abstaining from all food and consuming only water for a period exceeding 24 hours. This profound caloric deficit forces a metabolic switch to deep ketosis, significantly downregulates mTOR and IGF-1 pathways, and induces potent cellular autophagy. This process of cellular cleaning and renewal is a core mechanism targeted for healthspan extension.
Verdict
A potent but high-risk tool; requires careful medical supervision.
HEALTHSPAN IMPACT
High Value
RISK LEVEL
High
EVIDENCE GRADE
B
MONTHLY COST
$0 - $5000
Protocol
- A medically supervised fast of 3-7 days, performed 1-4 times per year to induce deep autophagy.
- A 24-48 hour fast performed weekly or monthly for less intense metabolic benefits.
Flags
- Requires medical supervision, especially for fasts longer than 48 hours.
- Contraindicated for individuals with eating disorders, who are underweight, or pregnant.
- Risk of refeeding syndrome, which can be life-threatening if not managed properly.
- May interact with medications for diabetes, blood pressure, and heart conditions.
- Significant muscle loss can occur without proper management or if performed too frequently.