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Fasting Methods & Protocols

Finding the right schedule for your lifestyle and goals

Choosing a Fasting Protocol

There's no single "best" fasting method—the right approach depends on your lifestyle, health status, goals, and personal preferences. Research supports various protocols, and what works well for one person may not suit another[1].

When starting, it's generally advisable to begin with a less restrictive method like 16:8 and gradually extend your fasting window if desired. This allows your body to adapt and helps you find a sustainable rhythm.

Common Fasting Schedules

16:8 Method

Also known as: Leangains Protocol, Time-Restricted Eating

16h fast8h eat

The most popular and beginner-friendly approach. You fast for 16 hours and eat during an 8-hour window. Many people achieve this by skipping breakfast and eating from noon to 8 PM.

Advantages

  • + Easy to maintain long-term
  • + Flexible meal timing
  • + Good entry point for beginners

Considerations

  • - May not trigger deeper fasting benefits
  • - Less effective for some weight loss goals

Best suited for: Beginners, those seeking a sustainable lifestyle change

18:6 Method

18h fast6h eat

A step up from 16:8, providing a longer fasting window while still allowing two meals. The extended fast may enhance metabolic benefits.

Advantages

  • + Enhanced fat burning potential
  • + Still allows multiple meals
  • + Natural progression from 16:8

Considerations

  • - Requires more planning
  • - May be challenging socially

Best suited for: Those comfortable with 16:8 looking for more benefits

20:4 Method

Also known as: Warrior Diet

20h fast4h eat

A more aggressive approach with only a 4-hour eating window. Originally popularized by Ori Hofmekler, this method typically involves one large meal and possibly a small snack.

Advantages

  • + Extended fasting benefits
  • + Simplified meal preparation
  • + May improve mental clarity

Considerations

  • - Difficult to meet nutritional needs
  • - Not suitable for everyone
  • - May impact social eating

Best suited for: Experienced fasters, those adapted to shorter eating windows

OMAD

Also known as: One Meal a Day

23h fast1h eat

You consume all daily calories in a single meal, typically eaten at the same time each day. This provides the longest daily fasting period.

Advantages

  • + Maximum fasting window
  • + Extreme simplicity
  • + Strong autophagy potential

Considerations

  • - Hard to meet calorie and nutrient needs
  • - May lead to binge eating
  • - Not recommended for most people

Best suited for: Very experienced fasters under medical supervision

5:2 Diet

Also known as: Fast Diet

You eat normally five days per week and restrict calories to 500-600 on two non-consecutive days. Not true fasting, but a form of intermittent calorie restriction.

Advantages

  • + Only two restricted days per week
  • + Flexibility in scheduling
  • + Easier social integration

Considerations

  • - Hunger on restricted days
  • - Requires calorie counting
  • - Not technically fasting

Best suited for: Those who prefer weekly structure over daily windows

Alternate Day Fasting

Also known as: ADF

24h fast24h eat

Alternating between regular eating days and fasting days (either complete fasting or very low calorie ~500 calories). One of the most studied fasting protocols.

Advantages

  • + Well-researched
  • + Significant potential benefits
  • + Clear structure

Considerations

  • - Very challenging to sustain
  • - May affect energy levels
  • - Social difficulties

Best suited for: Those willing to commit to a stricter protocol, ideally with medical guidance

Schedule Randomization

One limitation of sticking to the exact same fasting schedule daily is that your body may adapt over time. Some practitioners vary their fasting windows to prevent metabolic adaptation—this is sometimes called "metabolic confusion."

While large-scale research on schedule variation is limited, the principle of varied stimuli for continued adaptation is well-established in exercise science. Random Fast applies this concept by intelligently varying your fasting schedule within parameters you define.

Finding Your Protocol

Consider these factors when choosing a fasting method:

  • Experience level: Start with 16:8 if you're new to fasting
  • Work schedule: Align your eating window with your work and social life
  • Exercise routine: Time your workouts appropriately within your schedule
  • Health conditions: Consult your doctor before starting any fasting regimen
  • Sustainability: The best protocol is one you can maintain long-term

References

  1. [1] Tinsley GM, La Bounty PM. "Effects of intermittent fasting on body composition and clinical health markers in humans." Nutrition Reviews. 2015;73(10):661-674. View Source
  2. [2] Varady KA, et al.. "Alternate day fasting for weight loss in normal weight and overweight subjects." Nutrition Journal. 2013;12:146. View Source
  3. [3] Gabel K, et al.. "Effects of 8-hour time restricted feeding on body weight and metabolic disease risk factors." Nutrition and Healthy Aging. 2018;4(4):345-353. View Source
  4. [4] Wilkinson MJ, et al.. "Ten-Hour Time-Restricted Eating Reduces Weight, Blood Pressure, and Atherogenic Lipids." Cell Metabolism. 2020;31(1):92-104. View Source