The Complete Guide to Fasting for Longevity – Part I

Understanding Fasting and Longevity

Fasting, Longevity & mTOR

When it comes to fasting and longevity, caloric restriction appears to be a key factor. Caloric restriction and protein restriction have shown to increase lifespan and promote overall health. This brings us to an essential aspect of fasting—mTOR (mammalian Target of Rapamycin).

mTOR is a crucial growth switch in our bodies. Whenever we consume food, especially protein, mTOR is triggered, leading to tissue growth and muscle building. While growth is essential, extended periods of heightened mTOR activity can have detrimental effects on our health. Just as a house with multiple flaws can be problematic, our bodies also require intermittent breaks from continuous growth to consolidate and repair.

Fasting allows us to regulate the mTOR switch effectively. By incorporating strategic periods of fasting, we can create a balance between growth and consolidation efforts. Unlike the constant mTOR activation caused by frequent meals, fasting offers us the opportunity to turn this switch on and off deliberately, maximizing its benefits.

Protein Restriction & Benefits of Muscle

While protein is necessary for muscle development and maintenance, studies have shown that excessive protein intake may potentially shorten lifespan. Balancing protein consumption becomes crucial, as muscle mass plays a vital role in glucose metabolism, insulin sensitivity, and resilience against age-related conditions.

To navigate this dilemma, fasting provides a unique solution. During longer fasts, where the mTOR switch is turned off, one can safely increase protein intake without the risk of excessive mTOR activation. This provides an opportunity to repair and rebuild muscle tissue without compromising the longevity benefits associated with caloric and protein restriction.

What to Do: Fasting Strategies for Longevity

To harness the potential benefits of fasting for longevity, a structured approach is necessary. Here are some key strategies to consider:

Longer Fasts: Incorporate two days per week with extended fasting periods of 18 to 22 hours (or even 24 hours). During these fasting periods, autophagy (cellular recycling) is enhanced, and consolidation efforts occur, promoting health and longevity.

Protein Intake: On the days of longer fasting, it is beneficial to consume higher amounts of protein during the eating window. This allows for adequate protein synthesis and muscle repair, taking advantage of the anabolic window created by fasting.

Modified Fasts: On non-fasting days, consider implementing modified fasts, such as 14 to 16-hour fasting periods. During these periods, pay attention to the quality and composition of your meals to support the longevity benefits associated with caloric restriction.

Methionine Reduction: Methionine, an essential amino acid found abundantly in skeletal muscle meat, has been linked to accelerated aging. To mitigate its potential negative effects, consider incorporating organ meats into your diet, as they are lower in methionine and rich in essential nutrients. Additionally, periodic plant-based fasting can help reduce methionine intake and promote different longevity pathways.


Fasting, when approached strategically, may offer potential longevity benefits by combining caloric and protein restriction with intermittent mTOR activation and autophagy. Incorporating longer fasts, moderate protein intake, and periodic plant-based fasting can create a comprehensive approach to fasting for longevity. As always, it’s crucial to listen to your body and adjust fasting practices based on your individual needs and preferences.


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