Intermittent fasting protocol with 16-hour daily fast and 8-hour eating window, becoming most popular time-restricted eating method worldwide.

Origins

Time-restricted eating researched since 2000s, but 16:8 specifically popularized 2014-2016 through:

• Martin Berkhan’s LeanGains protocol (2010)
• Dr. Jason Fung’s fasting advocacy
• Silicon Valley biohacker adoption
• Reddit r/intermittentfasting community

Protocol

Standard schedule:

• Eating window: 12pm-8pm (most common)
• Fasting window: 8pm-12pm (sleep + morning)
• Water, black coffee, tea allowed during fast
• No calorie restriction required (but often happens naturally)

Variations:

• 12pm-8pm (skip breakfast)
• 10am-6pm (early dinner)
• 2pm-10pm (late eater)

Science & Benefits

Research-backed:

• Improved insulin sensitivity
• Enhanced autophagy (cellular cleanup)
• Fat loss while preserving muscle
• Cardiovascular health improvements
• Brain health (BDNF increase)

Mechanisms: Metabolic switching from glucose to ketones after 12+ hours fasting.

Mainstream Adoption

• 2014-2016: Early adopter phase (Reddit, forums)
• 2017: Silicon Valley endorsements (Jack Dorsey, etc.)
• 2018: Celebrity adoption (Jennifer Aniston, Hugh Jackman)
• 2019: Apps explosion (Zero, LIFE, BodyFast)
• 2020-2021: Pandemic weight loss surge
• 2023: Established mainstream practice

Social Media Culture

Instagram/Reddit dominated by:

• Fasting timer screenshots
• Weight loss transformations
• “What I eat in my eating window”
• Breaking fast meal photos
• Fasting streak milestones
• Blood glucose monitor data

Apps & Tracking

Zero Fasting: 15M+ downloads LIFE Fasting Tracker: 5M+ downloads BodyFast: 3M+ downloads

Features: Fasting timers, weight tracking, community support, science education.

Who Adopted It

• Tech workers: Productivity focus (no lunch break slowdown)
• Busy professionals: Simplicity (skip breakfast decision fatigue)
• Athletes: Muscle preservation + fat loss
• Health optimizers: Longevity benefits
• Diabetes patients: Blood sugar management

Criticism & Risks

• Disordered eating: Can mask restrictive eating disorders
• Social limitations: Conflicts with breakfast meetings, family dinners
• Not for everyone: Pregnant, diabetic (Type 1), history of eating disorders
• Hunger management: Some struggle with morning fasting
• Overeating compensation: Binge eating in window

Compared to Other IF Protocols

• 5:2 Diet: 2 days very low calorie per week
• OMAD: One meal a day (23:1)
• Alternate Day: Fast every other day
• 16:8: Most sustainable, easiest compliance

Sources

• Cell Metabolism: Time-Restricted Feeding30253-5)
• NEJM: Effects of Intermittent Fasting
• Reddit r/intermittentfasting (3M+ members)