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Health Benefits of Intermittent Fasting

The health benefits from fasting are endless. That being said, despite what many Intermittent Fasting (IF) zealots will proclaim, it’s not a magical bullet for weight loss. However, it is a powerful tool when used properly. Let’s look at some of the key health benefits of fasting.


Activating Anti-Aging Pathways

Activates Anti-Aging Sirtuin And Increases NAD+ 

Sirtuin genes were first discovered in yeast and described as a gene that, when increased, can make yeast and worms live longer. The sirtuin gene provides instructions to create the sirtuin enzyme. Resveratrol, an antioxidant found in red wine, activates sirtuins. 

In humans, activating sirtuins has anti-aging effects. It is unclear whether sirtuins prolong our lifespan, but it is clear that activating sirtuins:

  • Slows down the aging process
  • Improves healthspan
  • And helps with age-related diseases including:
    • Obesity
    • Insulin resistance
    • Diabetes
    • Skin aging
    • Cancers
    • And even cognitive decline and Alzheimer’s

Generally, eating increases NADH and reduces NAD+. Caloric restriction and fasting activates sirtuins by increasing NAD+, the molecule of youth.

intermittent fasting. clock, silverware and plate over a table

NAD+ (Nicotinamide Adenine Dinucleotide) to sirtuins is like a sharp but fragile knife for a butcher. Once sirtuins use the NAD+, it breaks down the NAD+ molecule into nicotinamide and ADP-ribose. 

Having more NAD+ also signals to the cells that your metabolism is going smoothly. It can amp up mitochondrial metabolism and increases the number of healthy mitochondria.

Increases Autophagy

Caloric restriction and fasting induce autophagy. Autophagy (auto = self, phagy = eat) refers to a cellular self-cleanup process where it breaks down old components to make building blocks available to rebuild new cellular components. 

This process also destroys unhealthy cellular parts, invading pathogens, and misfolded proteins. Some researchers believe that declining autophagy partly explains why inflammation and disease risks go up with age. 

Improving Metabolism and Metabolic Health

Resets Leptin And Insulin Resistances

Leptin is a hormone secreted from your fat cells. It tells your hypothalamus that you’ve got enough calories stored, so your hypothalamus adjusts your appetite accordingly. Mice without leptin are insatiable, burn less calories, and become very obese. When scientists injected these mice with leptin, they lost all the excess weight. 

Many obese humans are resistant to leptin in the hypothalamus. Many (but not all) of them are also insulin resistant. That means their hypothalamus can’t register how much body fat they have, so these people are hungry and full of cravings. Sleep deprivation and inflammation makes this worse.

If you have leptin and insulin resistances, and fasting is right for you, then fasting can be very beneficial for resetting these resistances. However, there are many situations where more gentler nutritional strategies would be more suitable. These include any history of disordered eating and if fasting ruins your stress markers and sleep quality. 

Reduces Inflammation And Promotes A Lean Gut Flora

Eating, especially eating high-fat meals, can increase blood bacterial toxins such as lipopolysaccharides. LPS induces inflammation and contributes to all kinds of modern diseases, including weight gain and obesity. Not eating temporarily reduces blood LPS. 

In obese mice, fasting both reduced blood LPS and promoted a lean gut flora. In metabolic syndrome patients, fasting shifted the gut microbiome and reduced their blood pressure.

Fasting also reduces inflammation in other ways, such as improving mitochondrial health and stimulating autophagy. If you’ve been eating inflammatory foods, fasting can obviously reduce inflammation from such foods. 

The Brain Benefits Of Fasting 

Many people experience a boost in focus, energy, and concentration during fasting.

Fasting also boosts brain derived neurotrophic factors (BDNF), which is kind of a fertilizer for your brain. Boosting BDNF will help keep your brain young and healthy. 

Fasting benefits the brain greatly by reducing inflammation and activating anti-aging cellular processes. Autophagy in the brain also helps clean up your neurons of unhealthy cellular debris. It also promotes brain healing and prevents many neurologic diseases.

plate clock , silverware and measuring tape over the table

Improved Neurochemistry

Before the ketogenic diet, fasting was a known way to manage epilepsy. That’s because ketones are so beneficial for the brain. More recently, psychiatrist Chris Palmer MD pioneered the use of fasting and ketogenic diets as treatments for psychiatric diseases. 

Many of his patients achieved better results from changing their diets than they could ever have with medications or standard treatments. That’s because poor blood sugar control and mitochondrial dysfunction underlie most brain and mental health conditions.

[If you’re diagnosed with any of these disorders, please undergo fasting and dietary changes with medical supervision as they can interact with your medications. Also, never go off or change your medications without speaking to your doctor first.]

Researchers hypothesized that the ketone body beta-hydroxybutyrate is sufficiently similar to gamma-hydroxybutyrate (GHB). Based on this hypothesis, BHB may partially bind to GABA receptors, which has a calming effect and overall slows down the activity of the brain. 

Fasting may also boost dopamine to drive your motivation to find food. This explains why fasting can boost mood for some people.

Fasting Is A Huge Time Saver 

The time you save by fasting is MASSIVE. How much time do you spend thinking about food every day?  “What am I going to eat for lunch? Dinner?” etc… Then there’s prepping the food, eating the food, and cleaning the plates and the kitchen. So fasting saves a massive amount of time.

Transform Your Emotional Relationship With Food 

One of the biggest benefits that almost everybody reports is that their emotional relationship with food changes. Our brains are hardwired to always be thinking about food, because it’s a key to survival. We’ve been conditioned to eat multiple times a day since we’re kids. 

Most people have never consciously gone a long period of time without feeding themselves. The majority of the world has a  “I must eat at least 3 times a day” mental program and fasting helps change that.

Fasting helps reduce the fear of, “If I don’t eat I’m going to die.” When we suggest people try fasting, oftentimes their initial reaction is: “I’d die.”  This is obviously not true but the only way to realize this is to go through a fasting experience.

Wade shares his initial fasting experience: “The first time I can remember fasting, there were struggles.  I can recall when I first started fasting, the first three days  really sucked. I was a guy that ate 5-6 meals a day for probably 10-15 years before I started fasting. Once I got through the first three days there I felt great.”

Biggest Intermittent Fasting Advantage: Ghrelin Shifting

plate with a clock and a fasting sign

However, there is ONE key advantage that is unique to IF: ghrelin shifting. 

Our bodies typically release a ghrelin spike 1 hour before your usual eating times. For example, if you typically eat breakfast at 9:00 AM, you will start to feel hungry around 8 am. Your body pings your brain and says, “Hey, get ready. I want to eat soon.” 

However, when you do IF for a few days, there’s a powerful adaptation that occurs: the ghrelin response changes. You lose that one hour ghrelin spike before the meal and that can be a game changer for managing hunger and lowering calories. By eliminating hunger a few hours a day, it can make it easier to eat less.

Some dieters find themselves living in a perpetual state of hunger when they eat 4-6 small meals a day. IF dieting can lower the amount of time that you experience hunger.  

Some people will push their fasting window to 18-6 (18 hours of fasting and 6 hours of eating).  That usually means, you’re eating maybe two meals and a snack. 

Some do 20-4 (20 hours of fasting and 4 hours of eating). Then some people do just one meal a day.  If you can manage the hunger, it’s hard to over-eat in an hour if you’re eating vegetables and good quality protein sources. However, if you’re going to pound a 14 inch pizza, it’s easy to go over your daily calorie target. 

Accelerated Ketosis And Fat Burning 

There is significant synergy between following a ketogenic diet and fasting.  Why?  Because since you’re already using fat for fuel, it’s easy for the body to keep using fats for fuel when there is no food present.  

Fasting will strengthen your fat adaptation. The longer you fast, the more ketones your body produces and better utilize them. That’s why the first fast is the most challenging for people. They haven’t built that biological adaptation to be able to convert fats into ketones easily. 


If you’ve never fasted before, intermittent fasting is a good place to get started.

First, you can start with 12 hours of fasting. This means if you start eating at 8 am, your last bite would be at 8 pm.  If you’re someone who is snacking until you go to bed, this is a BIG IMPROVEMENT.  First of all, your sleep quality will improve.  Second, you will probably lower your overall calories. 

From there, you can go 14-10:  14 hours of fasting and 10 hours of eating. This means if you start eating at 8 am, you would stop at 6 pm.

Many people promote the 16-8: 16 hours of fasting and 8 hours of eating. In general, the longer you fast, the more autophagy ramps up in the body.  These smaller eating windows MAY make it easier for you to eat less food.  However, to reiterate:  there’s no magic metabolic weight loss advantage to intermittent fasting. It does NOT ramp up your metabolism.  Your weight loss will still come down to CALORIES IN and CALORIES OUT.


The Nutrition Bible will teach you everything you need to know to achieve long-term nutrition benefits. 

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