Intermittent Fasting: An Unbiased Evaluation

The Benefits and Dangers

Intermittent fasting: What can it do? What can’t it do? Who would benefit from it, and how should they do it? Answers here.

Intermittent fasting has its benefits, but it also has its drawbacks. Here’s what you need to know.

The Bullet Points

  • Intermittent fasting is not a diet. It’s an eating pattern using compressing “windows” of food consumption.
  • Most effective intermittent fasts use 16-hour fasting periods with 8-hour feeding windows.
  • Being fasted does not mean you’re not eating. It means you have no nutrients available in the stomach or the bloodstream. If you eat a meal at 6 PM, you are not “fasted” at 6:01 PM or even 7 PM. You’re still digesting, and it could take several hours before you are truly fasted.
  • So, you’re not fasted for 16 hours; rather, you are not eating for 16 hours. If your last meal was large, you may only be truly fasted for 10 hours.
  • Intermittent fasting should follow the natural human biological rhythm or daily cycle. In that sense, you should be fasted during the active part of the day and eat when you’re in rest and recovery mode.
  • The best example of a true fasting approach is The Warrior Diet. This diet recommends one big meal per day, consumed in the evening.
  • Eating from 11 AM to 6 PM is technically “time-compressed eating,” but it’s not intermittent fasting.
  • Ending your fast by eating mostly crap food is not the best strategy. It’s not a green light to binge, but slipping into that habit and developing a poor relationship with food is easy. It can even cause fat gain even though you’re not eating for most of the day.
  • Intermittent fasting is not something I recommend for most people, especially for those who are already stressed. It can lead to chronically high cortisol levels.
  • Many people feel energetic when intermittent fasting, which feels good. But the reason they have so much energy is from elevated cortisol, which increases adrenaline levels. This backfires.
  • It’s nearly impossible to build muscle when intermittent fasting. It should only be used as a short-term strategy.
  • Check out my Primer 52 nutrition and training plan, which involves two strategic intermittent fasting days per week.

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