The Power of Fasting for the Prevention and Remission of Chronic Disease
Despite the recent spike in public awareness regarding the benefits of a simple fast, many people still live in fear/with a lack of understanding of the concept. Fasting is not dangerous, nor is it even difficult. I can give first person testimonial for the ease of fasting. After you sit with the hunger for several hours, it seems to recede. This can differ from person to person, but if you never try, you’ll never know! The benefits are innumerable, so bear with me:
Stage 1: The Fed State (0-3 Hours After Your Last Meal)
What Happens:
Blood glucose (sugar) levels rise after you eat.
Insulin increases to help lower blood sugar.
Hunger decreases (ghrelin drops), and you feel full (leptin increases).
Takeaway: In this stage, your body is busy digesting and absorbing nutrients from your last meal.
Stage 2: Glycogen Breakdown (3-18 Hours)
What Happens:
Blood glucose levels start to drop.
Your body taps into glycogen stores for energy.
For every gram of glycogen used, 3 grams of water are released—explaining early weight loss (mainly water weight).
Glycogen is a molecule that the body makes to store glucose. Glycogen is stored in the liver. The glycogen release alleviates a lot of water weight. For every gram of glycogen in the body, there must be 3 grams of water. A typical person will hold around 3 lbs of water in their glycogen stores. Every glycogen molecule holds ~30,000 glucose molecules. The body can burn this for many hours.
Hormonal Changes:
Insulin decreases (because there’s less glucose).
Glucagon, epinephrine, and cortisol increase, signaling your body to release stored energy.
Human growth hormone starts to rise, promoting tissue repair and muscle maintenance.
Takeaway: Your body burns stored glycogen, releasing water, and hormonal shifts set the stage for fat burning.
Stage 3: Fat Burning and Ketosis (18-48 Hours)
As glycogen stores are depleted, blood glucose levels drop but are maintained at a low level through gluconeogenesis. This decline in glucose availability triggers a process called lipolysis, primarily regulated by catecholamines like epinephrine and norepinephrine, as well as cortisol and ACTH, which are released from the adrenal glands. Glucagon, although not a catecholamine, also stimulates lipolysis, while insulin suppresses it.
During lipolysis, triglycerides in fat cells are broken down into fatty acids, which are then transported to the liver and mitochondria for oxidation. In the absence of sufficient glucose, these fatty acids are converted into ketone bodies through a series of chemical reactions. This marks the onset of ketosis, where the body shifts to using fat-derived ketones as an alternative fuel source.
What Happens:
Glycogen stores are depleted, and the body starts burning fat for energy through a process called lipolysis.
Lipolysis breaks down fat (triglycerides) into fatty acids, which are converted to ketones—an alternative fuel source.
Not only do you get to enjoy the benefits of ketosis, but you also trigger a process known as autophagy. Autophagy is reason in itself to begin a fast right now, especially if you are dealing with any chronic disease. Autophagy, by entomology, means self-eating. When you induce a state of autophagy, you begin to clear out and consume the parts of your body that are not functioning optimally. Think tumors, brain debris, joints, muscles, all being cleared of toxin debris and restored to an earlier state. When you let your body go through this process, you will emerge thinking clearer, with less inflammation and more energy. Keep in mind: the longer you keep it going, the more autophagy you will experience. Autophagy has been shown to continually increase for up to 72 hours of fasting.
Coinciding with the increased autophagy, your body will begin to release stem cells into the gut. After 24 hours, the number of intestinal stem cells more than doubles. These cells have the ability to decrease intestinal permeability, decrease gut inflammation, and even positively modulate the microbiome. The intrinsic ability of the human body to heal given the right conditions is something that modern medicine disregards to the detriment of patients worldwide.
When you fast for more than a day, you begin to experience a huge increase in human growth hormone. It has been consistently demonstrated that a 24+ hr fast will increase blood HGH concentrations by up to 5 times, bringing with it a consortium of benefits to your body. Growth hormone is essential for bone density, physical appearance and performance, sleep, and optimal brain functioning.
Along with growth hormone, the brain derived neurotrophic factor (BDNF), has been shown to explode in concentration upon an extended fast. BDNF is the primary driver of brain plasticity, the ability of the brain to form new connections (learning). Yes, fasting increases the brain’s capacity to learn.
Key Benefits:
Ketosis: The body burns fat instead of carbs, leading to weight loss and energy stability.
Autophagy: The body begins a "self-cleaning" process, clearing out damaged cells, proteins, and debris, including toxins. Autophagy is especially beneficial for chronic diseases and may even help eliminate unhealthy cells, such as precancerous cells.
Takeaway: Your body switches to fat burning and self-healing, promoting cellular regeneration and boosting metabolism.
Stage 4: Deep Fasting (48+ Hours)
If you make it this far on your first attempt, you are a very strong willed person. Congratulations. During stage 4, autophagy will continue to increase. Parallel to this, the immune system will continue to reorganize and replenish.
What Happens:
Autophagy continues to increase, clearing out old, damaged cells.
Your immune system begins to regenerate, and stem cells are released, helping repair and replenish tissues in the body (gut, heart, immune cells).
Growth hormone levels surge, reaching up to 5 times their normal amount, which supports tissue repair, muscle growth, and brain function.
Brain-Derived Neurotrophic Factor (BDNF) increases, enhancing brain plasticity and improving learning and memory.
As you get into the later stages, the body begins to release systemic stem cells into the bloodstream. These are cells that can differentiate into any cell in your body. If your heart is damaged, they will travel to your heart. If your lungs are damaged, they will travel to your lungs. Your immune system and blood cells generally will begin to reset and replenish. It has even been shown that new brain cells can be formed. The feeling is nothing short of euphoric. These are pathways that modern man never activates. Our ancestors were constantly fasted! Food is not so abundant in nature.
Takeaway: At this stage, your body is in full repair mode. Growth hormone and stem cells work together to regenerate tissues and improve overall health.
Tips:
While fasting, it is essential to stay hydrated. The body is burning fat and releasing the stored toxins with it. This burdens the kidneys. Stir a squeeze of lemon and a pinch of salt into your water for optimized electrolyte profile
Black coffee and tea also have the green light, and can be a great way to stay sane. Just don’t take too much as they will both spike your cortisol, which will already be elevated on a fast, and dehydrate you. A better option is matcha or other organic low or no caffeine herbal teas
Always break your fast with high-purity, nutrient-dense, whole foods. A few foods to break a fast include: organic fruits, pasture-raised eggs, fermented dairy, and homemade soups
