Intermittent Fasting

What is Prolonged Fasting?

Prolonged fasting refers to not eating food for extended periods, typically 48 to 72 hours or longer.  Depending on individual goals and health conditions, it may extend to a week or more.   

Fasting to prolonged fasting can be thought of similarly to walking and running.  Fasting from your last meal of the day, overnight to the first meal of the next, is something we all do without much thought.  Walking and running are things an able-bodied person can typically do without much thought.   

Intermittent fasting is more like walking or running for regular exercise.  There is more thought into when and how long you will perform the exercise, and specific goals are made around it.  OMAD is like a 20 km or 12.4-mile walk or run.  While a 20 km walk or run and OMAD intermittent fasting are challenging, they are doable for many who have planned, prepared and practiced shorter distances or fasting durations.   

Prolonged fasting is comparable to marathon walking or running.  Proper planning, preparation, practice, health monitoring, and recovery are essential to fasting and a marathon.  If a marathon (26.2 miles or 42.2 km) seems daunting, you should think similarly of a 48- to 72-hour prolonged fast.  Longer prolonged fasts should be viewed as entering an ultramarathon. The longer you go, the more preparation, planning, practice, health monitoring, and recovery are needed. 

This information is provided from Dr. Berg's Guidelines for Prolonged Fasting.docx.

Dr. Berg Nutritionals staff, including Dr. Berg Advisors, do not encourage prolonged fasting. We are not healthcare professionals equipped with the tests and facilities to perform the necessary monitoring during a prolonged fast, nor do we have an individual's medical health records. Dr. Berg Advisors provides this document based on Dr. Berg's education for informational purposes only to those already on a prolonged fast or independently choosing to do one.


Always consult with your healthcare provider before starting a prolonged fast.  If you're considering prolonged fasting, discussing the benefits and risks with your healthcare provider is essential.

Last updated: May 02, 2024 14:05 PM