Intermittent Fasting vs. Prolonged Fasting

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Intermittent fasting as a tool

Intermittent fasting is  typically considered to be a 16-18 hour window of fasting followed by a 6-8 hour window of eating. It can be used as a weight management tool IF you don’t compensate for the lack of calories during your shortened feeding window by stuffing your hungry face with whatever it is you’re craving. Used properly, along with a nutrient-dense nose to tail diet, you can make major changes in your physique and, more importantly, your health.

But… to add a tool to the toolkit, man (or woman) up and do the hard things in life, including a periodic long term fast to see very different, and very important benefits. Enter prolonged fasting of 48-120 hours.


We know you’ve heard of ketosis. The ketogenic diet is controversial, with mainstream doctors and publications pretending it will kill you and carnivore pushing doctors like Shawn Baker acting like you’re a complete and utter moron if you don’t go full keto right this minute. Like we articulated above, we don’t think keto is a long term solution to any problem because it tends to put your testosterone production in backward trajectory, but it’s definitely a tool in the toolbelt. So… here are a few of the benefits that you get when you enter ketosis, which begins somewhere around 14-16 hours after your last meal.

  1. Mental clarity. When you run out of carbs to burn, your body turns to creating alternative sources of energy. When you’re fasting, that energy production comes from fat metabolism. In order to do that, your liver produces ketones. These are fatty acid molecules that provide energy to your vital organs, including the brain. Ketones activate nerve cells that strengthen your intellectual capacity and create new cells from your brain’s cells. For a period, you can experience high levels of concentration and productivity, as well as emotional balance.
  2. Metabolic flexibility. When we’re constantly eating, and consequently digesting, our bodies become accustomed to only burning dietary carbohydrates to fuel your efforts. This means we never get to a point where we’re burning fat as fuel. This is also true on a ketogenic diet as your body is burning dietary fat rather than body fat. When we enter fasted ketosis, the body learns to utilize body fat for fuel. By doing this routinely, you teach your body to burn whatever energy source is most abundant. This leads to:
  3. Fat burning. When you’ve achieved metabolic flexibility, your body will burn body fat as a source of energy, meaning those abs you’ve been hoping for are no longer a dream.


Autophagy is a fancy Greek word that means “to consume oneself.” Whilst this sounds like autocannibalism, it’s not quite so dramatic. What autophagy does is impressive, however. As we age, some cells become sick, damaged, or mutated. These cells are aptly called “zombie cells” because over time they wreak havoc and infect the healthy cells around them. This can lead to the eventuality of disease… cancer in particular. But… When we free our bodies of the constant burden of digestion, our organs and tissues are able to take the time to engage in certain other activities. that they were made to engage in. This includes autophagy. During this phase, which begins 16-20 hours after your last meal, your body begins to “clean” damaged cells that can be repaired. If a zombie cell cannot be repaired, the body goes one step further and kills the cell. This is called apoptosis. During prolonged fasting of 72 to 120 hours, your body undergoes a self cleaning process that is incredibly valuable when it comes to disease prevention and longevity.

Growth hormone

About 48 hours after your last meal, a unique thing happens. Pituitary gland signals go into overdrive in order to protect your body from starvation. This leads to a fivefold increase in growth hormone production. This lasts through the 72 to 90 hour mark. This can result in feelings of elation and balance, but more importantly than your feelings, your body is healing and recovering at a depth that you cannot reach if you’re just eating all the time.

All of these processes were a regular part of the lives of our predecessors and were necessary for survival. If hunts were unsuccessful, they had to have the energy to continue to hunt. Otherwise our species would possibly have died out. Now, we lose out on the valuable bodily processes because we have become accustomed to stuffing our faces constantly with no regard for how we got here.

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