#044 Fasting Q&A with Dr. Rhonda Patrick and Mike Maser
Dr. Rhonda Patrick, PhD, answers common questions on fasting, covering coffee, supplements, amino acids, exercise, and breaking fasts. She discusses time-restricted eating, prolonged fasting, and the growth-longevity trade-off, emphasizing metabolic benefits and cellular repair.
Deep Dive Analysis
10 Topic Outline
Introduction to Zero Fasting Tracker and Dr. Patrick's Background
Impact of Coffee and Amino Acids on Fasting
Role of Electrolytes During Fasting
Comparing Different Fasting Methods and Their Benefits
Understanding Ketone Bodies and Their Metabolic Benefits
Effects of Exogenous Ketones on a Fasted State
Downsides and Benefits of Exercising While Fasted
The Growth-Longevity Trade-off and Fasting
Ideal Strategies for Breaking a Fast
Coffee Polyphenols and Autophagy Activation
6 Key Concepts
Circadian Biology
This refers to the natural daily rhythms of the body, including sleep-wake cycles and metabolic pathways. It's important to align food consumption with active metabolic pathways, which are more active in the morning and less so in the evening.
Autophagy
A cellular process where cells recycle and clear away damaged components, such as mitochondria or protein pieces. This 'spring cleaning' process is activated during fasting and requires the deactivation of growth pathways like mTOR and IGF-1.
IGF-1 (Insulin-like Growth Factor 1)
A 'grow-grow' pathway activated by amino acids and protein intake. While essential for growth, muscle repair, and neurogenesis, chronically high levels are associated with increased cancer incidence and can deactivate longevity pathways like FOXO.
mTOR (mechanistic Target of Rapamycin)
Another 'grow-grow' pathway that, like IGF-1, is activated by amino acids. Its deactivation during fasting is crucial for processes like autophagy to occur, allowing cells to recycle damaged components.
Beta-hydroxybutyrate (BHB)
A major circulating ketone body produced when the body shifts from glucose to fatty acid metabolism during fasting. BHB acts as a signaling molecule, activating genetic pathways that delay age-related diseases, increase repair processes, and make mitochondria more efficient.
Fasting-Mimicking Diet (FMD)
A specific, low-calorie, macronutrient-controlled diet developed by Dr. Walter Longo that aims to provide the benefits of prolonged fasting without complete food deprivation. It's designed to induce similar cellular and metabolic changes, such as organ shrinking and regrowth, seen in water-only fasts.
9 Questions Answered
While caffeine can slightly shift circadian clocks, studies show that consuming black coffee or tea without additives during a fasting window does not negate metabolic benefits like reduced breast cancer recurrence or improved blood glucose regulation and insulin sensitivity in time-restricted eating.
Yes, amino acids activate growth pathways like IGF-1 and mTOR, which need to be deactivated for key fasting benefits such as autophagy (cellular recycling) to occur. Consuming amino acids would interfere with this natural reduction.
For time-restricted eating, it's generally preferred to take electrolytes within the eating window. However, for prolonged fasts (48 hours or more), there is evidence that supplementing with electrolytes like sodium, potassium, and magnesium can be beneficial as the body starts to deplete them.
Different fasting methods offer distinct benefits; time-restricted eating aligns metabolism with circadian rhythms, while prolonged fasting (48+ hours) promotes stem cell activation and cellular regeneration. Combining these modalities, such as daily time-restricted eating with periodic longer fasts, can offer a comprehensive approach.
Exogenous ketones increase blood beta-hydroxybutyrate levels but can decrease circulating free fatty acids, suggesting they may prevent the body from mobilizing its own fat stores for ketone production. However, they can also prevent the use of amino acids from muscle, which is a beneficial effect.
Pre-feeding before exercise can improve long-duration aerobic exercise (over 60 minutes) and anaerobic exercise, but has less effect on shorter aerobic or high-intensity interval training. Training fasted can lead to robust enhancements in glucose sensitivity and mitochondrial adaptations for fatty acid use, though if doing fasted strength training, consuming protein within an hour post-workout is advisable to support muscle growth.
While high IGF-1 and mTOR promote growth (including muscle) but can increase cancer risk and turn off longevity pathways, a balanced approach involves periodic lowering of IGF-1 during prolonged fasts to clear damaged cells and activate stem cells, followed by refeeding with protein and carbohydrates to allow IGF-1 to rise and support rebuilding and muscle growth. Physical activity also helps direct IGF-1 to beneficial areas like the brain and muscle.
After a prolonged fast, it's ideal to break it with protein (amino acids) and carbohydrates to activate IGF-1 for stem cell growth and replenishment. It's important to ease back into eating, listening to your body, potentially starting with easily digestible foods like soups or small pieces of protein and fruit, and always avoiding processed foods and refined sugars.
Research suggests that the polyphenols found in coffee (even decaf) and tea can actually activate autophagy, rather than interfere with it. This implies that black coffee consumption during a fast may enhance the autophagy process.
21 Actionable Insights
1. Seek Medical Supervision for Prolonged Fasts
Consult with a medical professional before undertaking prolonged fasts (48 hours or more) to ensure safety and appropriate guidance, as these longer fasts may require medical oversight.
2. Practice Time-Restricted Eating Daily
Adopt a daily time-restricted eating pattern (e.g., 16-8) by consuming all food within an 8-12 hour window during the day when metabolism is optimal, and fasting for the remaining 12-16 hours to align with circadian biology.
3. Combine Fasting Modalities
Integrate daily time-restricted eating with periodic, longer fasts (under medical supervision) to leverage both regular metabolic benefits and deeper cellular cleansing and stem cell activation.
4. Avoid Late-Evening Eating
Refrain from eating late in the evening (e.g., after 8-9 PM) to prevent metabolic misalignment, which can lead to higher blood glucose levels and increased fat storage due to decreased insulin sensitivity and fatty acid metabolism.
5. Avoid Amino Acids During Fasting
Do not consume amino acids during a fast, as they activate growth pathways like IGF-1 and mTOR, which can interfere with beneficial fasting processes such as autophagy (cellular recycling).
6. Consume Electrolytes During Prolonged Fasts
Take an electrolyte supplement during prolonged fasts (48+ hours), especially if water-only, to replenish essential minerals like sodium and potassium that can become depleted.
7. Drink Black Coffee/Tea During Fasting
Consume black coffee or tea without caloric additives during fasting periods, as studies indicate it does not negate metabolic benefits and the polyphenols in coffee may even activate autophagy.
8. Train Fasted for Mitochondrial Adaptation
Engage in exercise in a fasted state to significantly enhance glucose sensitivity and prime your mitochondria for robust and efficient utilization of fatty acids as an energy source, an adaptation blunted by pre-exercise feeding.
9. Consume Protein Post-Fasted Strength Training
If performing strength training after a prolonged fast (e.g., 16 hours), aim to consume protein within an hour post-workout to support muscle growth and repair.
10. Direct IGF-1 with Exercise
Engage in regular physical activity and exercise to help direct the growth factor IGF-1 to beneficial areas like the brain and muscle, promoting neurogenesis and muscle repair, rather than allowing it to circulate and potentially stimulate damaged cells.
11. Maintain Healthy Lifestyle with High Protein
If you choose to consume a high-protein diet, ensure it is accompanied by a healthy lifestyle (e.g., physical activity, non-obesity, no smoking, moderate alcohol) to potentially mitigate increased mortality risks associated with high protein intake.
12. Break Prolonged Fasts with Protein & Carbs
When breaking a prolonged fast, consume a balanced meal that includes protein (especially essential amino acids) and carbohydrates to activate IGF-1, which is crucial for stem cell growth and cellular replenishment.
13. Ease into Eating After Prolonged Fast
After a prolonged fast, ease back into eating with easily digestible foods like small portions of protein (e.g., salmon), fruit, soups, or bone broths, as your gut may be sensitive and require a soft landing.
14. Avoid Binging Post-Fast
Refrain from binging immediately after breaking any fast, particularly longer ones, to allow your body to adjust gradually and sustain the health benefits achieved during the fasting period.
15. Prioritize Non-Processed Foods
Focus on a healthy diet rich in non-processed foods, including vegetables, healthy meats, and fatty acids, while avoiding refined sugars to support metabolic flexibility and overall well-being.
16. Consider Exogenous Ketones for Muscle Preservation
Be aware that exogenous ketones may help preserve muscle by preventing the body from using muscle amino acids for energy, a benefit also seen in prolonged natural fasting.
17. Exercise Performance and Pre-Feeding
For long-duration aerobic exercise (over 60 minutes) or anaerobic exercise (e.g., run to exhaustion), consider eating before to improve performance; for shorter aerobic exercise or high-intensity interval training, pre-feeding has less impact on performance.
18. Use Zero Fasting Tracker
Utilize the Zero Fasting Tracker app to easily monitor and manage your fasting times, whether for time-restricted eating or longer fasting protocols.
19. Explore Found My Fitness Episodes
Visit foundmyfitness.com/episodes to access a wealth of expert conversations and resources on various health and longevity topics.
20. Follow Zero for Updates
Visit zerofasting.com or follow @ZeroFasting on Twitter to stay updated on new features and information from the Zero Fasting Tracker.
21. Listen to Foodist Podcast
Tune into Dr. Daria Rose’s ‘Foodist Podcast’ for discussions on topics such as DHA, Alzheimer’s prevention, and pregnancy-related health.
5 Key Quotes
If IGF-1 is around and expressed at a high level, it's kind of around going, no, no, no, grow, grow, grow, you're cool, you can stay, I'm here, forget about the damaged cell, let's just move on.
Dr. Rhonda Patrick
Your body has this beautiful way of doing that and it's called programmed cell death or apoptosis, basically kill the cell.
Dr. Rhonda Patrick
If you fast a mouse, a rodent, for 48 hours, they lose 20% of their body weight. A human loses maybe 2%.
Dr. Rhonda Patrick
It's like a completely different fuel, glucose to ketones. It's amazing that our bodies can even do that.
Mike Mazur
It used to be thought like, there's this one hour window and you have to down this protein shake immediately or you're going to miss it. I don't think that's the case.
Dr. Rhonda Patrick