Equipment Reference
Satchin Panda PhD
The Circadian Code (Paperback)
Satchin Panda on when you eat — time-restricted eating from the Salk lab
Salk Institute circadian biologist Satchin Panda’s practical book on aligning light, meals, and sleep with the body clock. The headline protocol is time-restricted eating — typically an 8–12 hour eating window — plus morning light and evening darkness. Pair with our circadian-rhythm and intermittent-fasting guides.
Typical price: $14 – $20 USD
How It Works
Panda’s mouse and human TRE work is a major reason ‘when you eat’ entered longevity Twitter. Human metabolic benefits are promising and still being sized. This is not a calorie-free pass — window plus food quality both matter.
Clocks in Every Organ
Liver, gut, and fat have clocks set by when you eat, not only by the brain’s light clock.
Eating Window
Compress food (and caloric drinks) into a consistent daytime window. 12 hours is a start; 8–10 is the research-adjacent range.
Light + Sleep
Outdoor morning light, dim evenings, and a regular bedtime — TRE without sleep is half a protocol.
What You'll Experience
Week 1
Days 1–7Stop after-dinner snacks. Late coffee counts. Hunger moves earlier within days for many people.
Habit
Weeks 2–8Sleep and fasting glucose anecdotes are common. Track energy, not just scale.
Benefits
Free Metabolic Lever
Moderate EvidenceNo device required — a kitchen clock and consistency.
Pairs With Sleep Work
Moderate EvidenceBest companion book to Walker if your problem is late eating, not only late screens.
Risks & Considerations
Eating Disorders / Pregnancy
high riskCompressed windows are a poor idea if restriction is already pathological, or in pregnancy without a clinician.
Diabetes Meds
high riskChanging meal timing on insulin or sulfonylureas needs medical supervision.
Community Reviews
Synthesized consensus from Reddit, forums, and expert sources.
Readers implement the window immediately. Scientists praise the mechanism chapters; some want more human outcome tables.
- ·12-hour window is the on-ramp
- ·Light matters as much as food
- ·myCircadianClock app mentioned
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