006: Live Longer and Get Shredded By Eating Less Often

Episode Notes:
The ancient practice of fasting has become mainstream again. Is it just another weight loss trend, or is there more to fasting than simply starving yourself? Determined to fully understand the benefits of fasting, I experimented with variations of intermittent fasting and a 120-hour water fast. The results? In a matter of weeks, fasting changed my life. I eliminated brain fog and daily energy lulls, increased energy and productivity, got shredded, and became a happier and healthier person. Fasting has become a critical part of my optimization plan by improving my health, happiness, and performance.

In this episode, you are going to learn how fasting can be applied to drastically improve your life, by inducing autophagy (cellular cleansing), engaging your survival circuit, burning fat, developing metabolic flexibility, enhancing cognition, and much more!

Topics:
[2:10] Fasting for longevity: Understanding autophagy and mTOR
[5:27] Fasting-induced ketogenesis and gluconeogenesis
[7:27] Improved cognitive functioning resulting from intermittent fasting
[9:40] Losing 22lbs in six weeks and 9lbs in five days
[11:55] Using eating windows to manipulate weight gain and weight loss
[13:01] How to get started with fasting

Thank you all for joining me on this journey to lifelong health, happiness, and higher performance. And remember, always be grateful, love yourself, and serve others.

Teaser
In this episode… After 25 years of researching aging, Sinclair’s best piece of advice to stay healthy longer, is to eat less often. Not eat less, just eat less often. He explains that caloric restriction activates the survival circuit by engaging sirtuins…

Topic Introduction
Learn II Perform: Practical lessons so that you can immediately learn to optimize your health, happiness, and performance.

Gratitude
For this episode’s gratitude shoutout, I want to express gratitude to Peter Attia, one of the leaders in the science of longevity and well-being, for exposing me to the amazing science behind fasting. My first introduction to the magic of fasting came from a video of Peter Attia with Joe Rogan, and I was immediately hooked [1]. So thank you to Peter Attia for spreading information and Joe Rogan for providing a platform for thought leaders to share their knowledge with the world! The link to the video will be included on the website.

Intro
Alright, today’s episode is about fasting – an approach to health, happiness, and high performance that I swear by. Although fasting may seem like the latest trend, and it was relatively new to me when I discovered it at the start of the pandemic, it is one of the oldest health practices that has been traced back over 2,000 years. Notable historic supporters of fasting include Hippocrates, the ancient Greek physician known as “the father of medicine,” dating all the way back to the fifth century BC, and some very recognizable religious figures including Jesus Christ, Prophet Mohammed, and Buddha [2].

So What’s the Bottom Line
Many people are skeptical and uncertain about fasting. What you will discover is that it is one of the most powerful mechanisms for optimizing your life, capable of providing three key benefits:

1. Increased longevity
2. Increased fat loss
3. Higher Performance

But before we dive in, an important disclaimer. This is not medical advice and I am not a medical professional. You are encouraged to seek professional medical advice before proceeding with any significant lifestyle changes, including the implementation of fasting. Thanks to biochemical individuality, everyone is different, so while certain techniques may work for one person, another person may not respond the same.

1. Increased Longevity
When considering aging mechanisms, I will call upon Dr. David Sinclair’s book, Lifespan [3]. After 25 years of researching aging, Sinclair’s best piece of advice to stay healthy longer, is to eat less often. Not eat less, just eat less often. He explains that caloric restriction activates the survival circuit by engaging sirtuins. In short, sirtuins are cellular enzymes that maintain physiological homeostasis, assisting with DNA repair, insulin sensitivity, neurogenesis (which is the development of new brain cells), inflammation management, and delayed aging, among other cellular processes [4, 5].

An important consideration with longevity genes and fasting must be given to the relationship between autophagy – the cellular process of eating and recycling dead and senescent cells – and the mammalian target of rapamycin, commonly referred to as mTOR [3, 6, 7]. The mTOR pathway is responsible for regulating cell proliferation and life span. In the presence of excess nutrients, times are good, and the mTOR pathway is activated, enabling cells to continue to grow and divide. So, while constantly consuming calories, cells will continue to grow and divide.

The opposing pathway is autophagy, in which dead cells are recycled and removed. In this phase, the cells essentially begin to eat themselves to supply sufficient fuel. Fortunately, this self-consumption is just the recycling of cells – breaking them down into their basic elements and repurposing them as required [8]. The cells targeted for recycling are the dead, senescent, and potentially cancer-inducing cells.

Now, because these two pathways are regulated by each other and perform opposite tasks, the body cannot perform cellular cleaning through autophagy while the mTOR pathway is activated. Thus, if you are constantly eating, your body never has a chance to recycle and remove dead, and potentially cancerous, cells.

Here’s a great metaphor. When you eat all the time, it is like have a steady incoming cash flow. You are guaranteed to receive $1,000 deposited into your bank every day. So, what do you do? You go out and spend the money on more food, more items, more everything! And you repeat that process every day. That’s mTOR – that’s our cells dividing when we are constantly feeding.

Now imagine that suddenly the money stops coming in, and you have no idea when your next paycheck will be. All of a sudden, your survival instincts kick in, and you immediately stop spending, because you can’t afford to. But soon you need money, so what do you do? One way is to take items you have but don’t need and put them for sale, allowing you to use your excess reserves to sustain yourself. That’s autophagy – recycling old cells until you have a new source of intake.

Ben Greenfield, a world-leading fitness expert, cites evidence that fasting has the same effect for the brain, a process called neuronal autophagy, which he summarizes as “the intentional and healthy self-destruction of aging neurons to make room for new ones” [9]. When frequently feeding, especially on sugars and proteins, insulin levels are elevated, and neuronal autophagy is restricted, which is associated with increase onset of neurodegenerative diseases including Parkinson’s and Alzheimer’s.

By performing cellular cleansing, autophagy has been repeatedly linked to anti-aging mechanisms, disease prevention, and increased lifespan [10, 11, 12, 13].

2. Increased Fat Loss
One of the main reasons people implement fasting is to lose fat, and for good reason. However, it is important to note that fasting is not a diet. There are no requirements to what you eat or how much. The only is change is when you can eat, often making this much easier to implement than restrictive diets.

One of the primary mechanisms occurring when fasting, as noted by fasting expert Peter Attia, is the body entering a state of ketosis as glycogen reserves are used up, switching your primary fuel source from carbohydrates to fat-derived ketone bodies [14]. Although a topic for another episode, ketosis has been shown to have numerous health benefits, including weight loss, improved blood pressure, improved blood glucose regulation, and enhanced cognitive performance [15, 16, 17].

Back to fasting-induced ketosis. The ketones produced in ketosis have actually been shown to provide up to 50% of metabolic and 70% of the brain’s energy requirements [18, 19]. Therefore, the achievement of ketosis through fasting or dietary restrictions enables pertinent functionality of the brain and body without the need for carbohydrates.

So where exactly do ketone bodies come from? The answer – a process called gluconeogenesis. With gluconeogenesis, non-carbohydrate substrates are transformed into readily available glucose [20]. The primary gluconeogenic precursors are lactate, amino acids – predominantly glutamine and alanine – and glycerol, which is stored in fat [20, 21, 22]. While fasting, the most readily available gluconeogenesis precursor is the glycerol found in stored body fat. Essentially, when in a fasted state – also referred to as a metabolic state of starvation – glycerol can be recruited from fat to provide ketone bodies in lieu of glucose.

Therefore, through fasting, you can obtain the fat-burning state of ketosis more frequently and more easily. As your body becomes adapted, you will acquire the metabolic flexibility to easily switch to fat-burning as a primary fuel source when in a fasted state. This can help you turbocharge your fat loss.

3. Higher Performance
This show is all about optimizing human performance and a big part of being a high performer is becoming highly efficient with your time and energy. Fasting can help. First all of, with restricted feeding, you will be reducing the total number meals eaten during a day. Fewer meals mean less cooking, less cleaning, and less time spent eating. This leads to something we all need – more time! Think about how much of your day is allocated to meals. Over time, that adds up significantly and meals can very often interrupt work flow.

Saving time and energy invested into eating is great, but what about increased performance? Many people claim to have improved cognitive performance when fasting, particularly learning, memory, and focus. Research is ongoing, but here are some insights into how this happens.

One 2013 study on mice found that intermittent fasting increased learning and memory while suggesting that “intermittent fasting reduces oxidative stress in the brain” [23]. This is because oxidative stress has been linked to impaired learning and memory [24, 25]. One possible mechanism was the increase in brain-derived neurotrophic factor, commonly referred to as BDNF, although the study found that BDNF is linked more closely with caloric restriction than intermittent fasting. However, for fasts 24 hours or longer, Dr. Mindy Pelz [26] notes a rise in BDNF, a growth factor involved in neurogenesis and neuroplasticity by building new dendrites and synapses, promoting enhanced learning and memory [27, 28].

Other mechanisms of improved cognitive function have also been suggested. A 2017 mice study concluded that intermittent fasting regulates an inflammatory response pathway that influences cognitive function [29]. Meanwhile, a 2016 study in Neuron proposed that “nutritional scarcity could acutely influence synaptic homeostasis and functional stability in neural circuits” [30]. One more theory is that neuroplasticity and brain health are improved by metabolic switching [31]. A 2018 study offers that intermittent metabolic switching, such as repeated cycles of fasting-induced ketosis and eating, “may optimize brain function and resilience throughout the lifespan, with a focus on the neuronal circuits involved in cognition and mood” [31].

What about that post-meal fatigue that we all experience? It has been shown that feeding has a drastic impact on numerous hormones, including melatonin, meanwhile the vagus nerve – which forms the gut-brain connection – is activated [32]. As hormones and systems adapt to food intake, a 2018 study demonstrated that interleukin-1 (an inflammatory molecule) is actively involved in the regulation of post-feeding fatigue [33]. A separate study suggested that “Brain ‘fog’ may be due to inflammatory molecules… causing focal brain inflammation” [34].

What this means, is that it is very possible that fatigue after eating is caused by an inflammatory response. The alternative, fasting, works to reduce inflammation. This may be the critical link between fasting and improved cognition, ultimately leading to higher performance.

My Experience
But enough of the science, I want to share my experience.

After learning about fasting, I began to implement intermittent fasting in addition to fasted workouts. After what was an unhealthy bulking phase consuming everything and anything, I weighed 197lbs and wanted to shred off my fat for the summer. The plan was to train in the mornings, and then eat between 12pm and 8pm. After adapting, I began to decrease my feeding window, achieving a four-hour window from 4pm to 8pm within a few weeks. I should also note that I was following a ketogenic diet at the time.

Within a month, I had lost about 15lbs and was close to 180lbs. I felt way better, had more energy, slept better, had better workouts, drastically reduced brain fog, and my body fat had melted away. My focus and mental cognition during the day were laser sharp – I had never been so productive. I was learning four languages, reading over a book a week, and learning instruments.

Tempted for the next challenge, I was exploring the numerous health benefits of prolonged fasts. Rather impulsively on a Sunday night, I decided I was going to do a 120-hour water fast. Zero calories, just water supplemented with sodium, potassium, and magnesium. This changed my life and is something I’ll go into detail on in a future episode.  

During that water fast, I lost an additional 9lbs in 5 days, while working out every single morning, including a two-mile run 111 hours into my fast. My focus and mental clarity peaked, all my sugar and food cravings were eliminated, and my taste palette was completely reset. I now genuinely love of 100% cocoa dark chocolate, something that used to be much too bitter to enjoy. That was a wonderfully welcome benefit of the prolonged fast.

Following an appropriate refeeding phase, my weight stabilized at about 175 lbs, 22 lbs less than my starting weight in a matter of about six weeks. At this point in time, I had the lowest body fat of my life. In fact, I could actually see and feel little imperfections and bumps on my ab muscles, because my fat levels were so low.

For the sake of feeling amazing, I decided to continue with one meal a day for another two months. Initially, I continued with keto, but then experimented with a 100% whole foods, plant-based diet for three weeks. Despite switching from 30g of net carbs a day to over 400g carbs, including over 100g of natural sugars, I did not gain any additional fat. And just a note, my total calorie intake remained the same.

Then, I decided I wanted to build muscle and gain some lean weight back. Despite increasing calories and resistance training, I didn’t have much luck. At this time, I theorized that the suppression of the mTOR pathway was the reason I wasn’t gaining weight. My hypothesis was that if I increased my feeding window back to eight hours daily while maintaining the exact same nutrition profile – calories and macros – I would start gaining weight due to an increased activation of the mTOR pathway responsible for cell proliferation and growth.

Sure enough, after opening up my window to 8 hours again – while eating a balanced diet of nearly 100% whole foods, I was able to gain nearly 10lbs of mostly lean mass within a month.

To this point, I have maintained a comfortable weight of 185lbs, and regularly alternate between different fasting windows and nutritional profiles to maintain metabolic flexibility.

Overall, I truly feel healthier. When I practice longer fasting periods, I have better mental clarity, much less brain fog, increased energy, and genuinely feel better. I firmly believe that fasting helps my body to remove excess cellular waste, which is why I now perform at 48 hour water fast at the beginning of every month, and intend to do a 120 hour fast every six months.

So What You Can Do
As we learned, fasting can add years to your life, shred pounds off your body, and help to eliminate brain fog and fatigue.

If you are interested, the first recommended step is to consult with a medical professional, get your bloodwork tested, and be sure that fasting is something that you would like to try. It is not recommended for people with diabetes, pregnant women, children, people with a history of eating disorders, and some people with other medical complications [35].

Now, to practice fasting, there are a few common variations. Many people who apply daily intermittent fasting will choose to skip breakfast, often choosing to eat between 12pm and 8pm, for example. While this 16:8 ratio is common, eating windows range from 12 hours to 1 hour, with just one hour also known as one meal a day, or OMAD. Another common form is the 5:2 ratio, in which people will eat regularly for five days a week, with two designated days having a highly restricted caloric intake, such as 500 calories for the day [36]. There is also alternate day fasting and prolonged fasts ranging from 24 hours to multiple weeks. Clearly, there is a lot of flexibility and customization to each person’s specific goals, needs, and health.

The easiest way to start is by skipping breakfast. Give yourself a week of eating in a compressed window. Be patient as your body adapts and you will notice your hunger cravings will subside over time. For bonus benefits, try working out in a fasted state to spark ketosis.

And if you are really ambitious, I would then try to work your feeding window down to six hours, and then maybe four hours. To help maximize benefits, a ketogenic diet will increase time spent in ketosis, and the reduced carbohydrate intake – particularly sugar – can help to curb food cravings.

While this may not work the same for everyone, fasting has changed my life and is something I intend to employ for the rest of my life. If you search for case studies and forums on fasting, you will find thousands of other people who have drastically improved their lives – some truly incredible transformations – just by eating less often. Not eating less, just eating less often.

To close, I hope that you got some useful information out of this science-heavy episode, but if you have any questions or comments, I’d love to hear from you. And if life gets in the way and you happen to miss a meal, don’t feel bad about it, because it may be for the best.

As Plutarch, an ancient Greek philosopher was attributed to saying: “Instead of using medicine, rather, fast a day” [37].

Episode Outro
To discover more, the full transcript of this episode with all citations is available on the website and you can also contact me on social media with any questions or comments. If you found this episode useful or think that it may help someone else, I encourage you to pass it along.

Thank you all for joining me on this journey to lifelong health, happiness, and higher performance. And remember, always be grateful, love yourself, and serve others.

Resources
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