Podcast Summary: "Could Fasting Extend Your Lifespan?" | Dr. Valter Longo and Prof. Tim Spector

Release Date: January 23, 2025

Introduction

In this enlightening episode of ZOE Science & Nutrition, host Jonathan Wolf delves into the intriguing topic of aging with two esteemed guests: Dr. Valter Longo, Director of the Longevity Institute at the University of Southern California and a pioneer in aging research, and Professor Tim Spector, a renowned epidemiologist and co-founder of ZOE. The discussion centers around the concept of biological age versus chronological age and explores how dietary practices, particularly fasting, can influence longevity and overall health.

Understanding Biological Age vs. Chronological Age

Dr. Valter Longo introduces the fundamental distinction between chronological age—the number of years one has lived—and biological age, which reflects the health and functionality of an individual's cells.

“Biological age is determined by how functional you are, how able you are to reproduce, to run fast, et cetera” (04:57).

Key Points:

• Biological age can differ significantly from chronological age.
• Factors such as cell health impact biological age more profoundly than the passage of years.
• Lowering biological age can reduce the risk of chronic diseases like Alzheimer's, diabetes, and cancer.

The Genetics of Aging

The conversation shifts to the genetic aspects of aging. Dr. Longo shares insights from his research, highlighting how specific genetic pathways influence longevity.

“If you have a lot of growth hormone, the receptor is activated and they're lacking this receptor. Right. So they're not able to…” (20:27).

Key Points:

• Genetic mutations can dramatically affect lifespan in organisms, as evidenced by studies in mice.
• In humans, genetics account for approximately 20% of aging influences, with the remaining 80% driven by environmental and lifestyle factors.
• Certain populations, such as those in Sardinia's "blue zones," exhibit remarkable longevity potentially due to favorable genetic variants combined with healthy lifestyles.

Influence of Diet and Fasting on Aging

A major segment of the discussion revolves around how diet, particularly fasting, impacts the aging process. Dr. Longo emphasizes that fasting can revolutionize gene expression more effectively than many other interventions.

“Find me anything that will revolutionize gene expression more than fasting.” (26:57).

Key Points:

• Fasting induces significant physiological changes, shifting the body from using external energy sources to internal reserves like fat and ketone bodies.
• Autophagy, the process where cells recycle damaged components, is a crucial benefit of extended fasting, typically initiating after five days of water-only fasts.
• Intermittent fasting methods, such as time-restricted eating, offer varying benefits but must be approached cautiously to avoid adverse effects like increased mortality.

Time-Restricted Eating and Its Effects

Professor Tim Spector elaborates on ZOE's large-scale study involving 140,000 participants who adopted a time-restricted eating window of 10 hours, fasting for 14 hours daily.

“A third of people found it really easy to do this and they actually carried on well past the three weeks…” (32:57).

Key Points:

• Time-restricted eating can lead to improved mood, increased energy, weight loss, and reduced waist circumference.
• Adherence varies, with one-third finding it easy, one-third struggling to start, and the remaining third discontinuing the practice.
• Sustainable, moderate fasting windows (e.g., 12-hour fasts) are recommended over more extreme fasting durations to maximize benefits while minimizing risks.

Fasting Mimicking Diet: Concept and Benefits

Dr. Longo introduces the Fasting Mimicking Diet (FMD), a meticulously designed low-calorie, low-protein, low-sugar, high-fat, plant-based regimen that simulates the effects of prolonged fasting without complete food deprivation.

“It's a low calorie, low protein, low sugar, high fat, plant based diet that lasts between four days and seven days...” (36:20).

Key Points:

• FMD is intended to be undertaken periodically (e.g., five days every three months) to confer health benefits without the impracticality of continuous fasting.
• Clinical trials have demonstrated that FMD can lead to significant improvements in conditions like diabetes, reducing the need for medication in 70% of participants.
• Ongoing research aims to evaluate the long-term sustainability and efficacy of FMD in various populations and health conditions.

Studies and Findings

The guests discuss various studies underpinning their claims. Notably, Dr. Longo mentions trials where FMD led to a reduction in biological age by approximately two and a half years after just three cycles.

“Subjects that were asked to do the fasting, making diet monthly for three months, they showed a reduction almost identical in both trials of 2.5 years on average.” (41:27).

Key Points:

• FMD has shown promising results in reducing biological age markers and improving kidney function in preliminary studies.
• Long-term studies are underway to assess the durability of these benefits and potential long-term effects.
• The response to FMD varies among individuals, emphasizing the need for personalized dietary approaches.

Practical Recommendations

Both experts offer actionable advice for listeners interested in leveraging fasting for health and longevity:

1. Time-Restricted Eating:

   • Adopt a balanced approach, such as a 12-hour eating window, to promote metabolic health without adverse effects.
   • Avoid extreme fasting durations (e.g., 16-20 hours daily) to prevent potential health risks.

2. Fasting Mimicking Diet (FMD):

   • Follow a clinically tested FMD protocol, typically involving 600-1,100 calories per day over five days.
   • Undertake FMD periodically (e.g., three times a year) to maximize health benefits while ensuring sustainability.

3. Holistic Lifestyle:

   • Complement fasting practices with a diet low in ultra-processed foods and rich in plant-based nutrients to reduce inflammation and support gut health.
   • Maintain muscle mass through exercise and engage in other healthy lifestyle practices to support overall longevity.

“Your daily food you're eating when you're not fasting is also really important because we know that particularly ultra processed foods are going to be pro inflammatory...” (49:41).

Conclusion

The episode underscores the profound impact of dietary interventions, particularly fasting, on biological aging and overall health. Dr. Valter Longo and Prof. Tim Spector provide compelling evidence that strategic fasting practices, such as the Fasting Mimicking Diet and moderate time-restricted eating, can significantly enhance longevity and reduce disease risk. However, they also caution against extreme fasting regimens and emphasize the importance of a holistic approach to diet and lifestyle for sustainable health benefits.

Listeners are encouraged to consult with healthcare professionals before embarking on significant dietary changes and to consider personalized approaches to fasting and nutrition to optimize their health and longevity.

Notable Quotes

• Dr. Valter Longo at [04:57]: “Biological age is determined by how functional you are, how able you are to reproduce, to run fast, et cetera.”

• Dr. Valter Longo at [26:57]: “Find me anything that will revolutionize gene expression more than fasting.”

• Professor Tim Spector at [32:57]: “A third of people found it really easy to do this and they actually carried on well past the three weeks…”

• Dr. Valter Longo at [36:20]: “It's a low calorie, low protein, low sugar, high fat, plant based diet that lasts between four days and seven days…”

• Dr. Valter Longo at [41:27]: “Subjects that were asked to do the fasting, making diet monthly for three months, they showed a reduction almost identical in both trials of 2.5 years on average.”

For more personalized nutrition insights and to explore how you can optimize your biological age, visit ZOE.com and consider joining their tailored nutrition program.