In this article, in collaboration with nutrition professionals, I will take a detailed look at what happens to your body when you don’t eat for 100 hours (4 days and 4 hours). This process may seem extreme, but it’s important to understand that our bodies are designed to survive and have reserves to draw on in such situations. This article explains how the body adapts and what changes occur during these 100 hours.
Table of Contents
The first 12 hours: Digestion and insulin
During the first 12 hours, the body is mainly engaged in digesting the previous meal. Food passes from the stomach to the intestines and is processed. During this time, insulin levels also decrease. Insulin is a hormone that helps regulate blood sugar levels. After eating, insulin levels increase to help cells take in glucose from the blood. When we don't eat, insulin levels decrease and the body begins to use stored resources. You may also notice a slight loss of water during this stage.
2-4 p.m.: Mental clarity and ketones
After about 14-16 hours, people often experience mental clarity. This effect is caused by a redistribution of energy in the body. Once the digestive process is complete, the energy previously used for digestion is now available for other processes, including the brain. The brain is the most energy-intensive organ, consuming approximately 20% of the body's total energy. Also, around this time, ketone production begins. Ketones are substances produced when fat is broken down, and they can serve as an alternative source of energy for the brain.
16-17 hours: Autophagy and counter-regulatory hormones
At around 4-5 p.m., autophagy begins. Autophagy is the process by which the body “eats” damaged or dysfunctional cells, thereby cleansing itself of waste. This process is crucial for cellular health and can help prevent various diseases.
In parallel with autophagy, counter-regulatory hormones such as cortisol, glucagon, and growth hormone are also activated. These hormones help the body obtain energy and maintain normal blood glucose levels. These hormones can increase energy levels and improve concentration.
24 hours: Intestinal tract regeneration
After 24 hours, the body experiences a period of intestinal regeneration. During this time, the intestinal tract has rested from the digestive process and the body can focus on rebuilding itself. This process can help improve gut health and reduce problems like gas, bloating, and heartburn.
36 hours: Fat burning
After about 36 hours, the body begins to actively use stored fat as an energy source. This process leads to weight loss and an increase in ketone levels.
72 hours: Immune system recovery and dopamine reset
After 72 hours, the body experiences a recovery of the immune system. During this time, stem cells are activated, which help restore the immune system and improve its functions. Also, around this time, dopamine “reset". Dopamine is a neurotransmitter associated with pleasure, motivation, and reward. Prolonged fasting can help restore dopamine receptor sensitivity and improve mood.
100 hours: Stem cell influx and cell renewal
At the end of the 100-hour fast, the body experiences an influx of stem cells. These stem cells can be used to repair damaged cells and tissues in various parts of the body. This process can help improve health and promote regeneration.
Questions and answers
- Do you lose muscle mass when fasting? Short-term fasting, such as 100 hours, usually does not cause significant muscle loss. The body first uses stored fat as an energy source.
- What can you drink while fasting? It is recommended to drink only water and electrolyte solutions during fasting. Coffee and tea can affect blood sugar levels and reduce the effects of fasting.
- Can you exercise while fasting? It is not recommended to do intense exercise while fasting. It is better to choose light activities, such as walking.
- How to properly stop fasting? It is recommended to break the fast gradually, starting with light foods such as broth, eggs, and avocado.
This article provides a detailed overview of what happens to the body during a 100-hour fast. It is important to remember that you should consult a doctor before starting a long-term fast.
Weight loss after 100 hours of water fasting
Body mass can vary significantly depending on several factors, including:
- Body composition: People with more muscle mass tend to have faster metabolisms, which means they can lose more weight than people with less muscle mass.
- Physical activity: If you are physically active, you are more likely to lose more weight than if you are sedentary.
- Metabolism: Everyone's metabolism is different, and this can affect weight loss.
- Stress and sleep: Stress and lack of sleep can affect weight loss.
However, it is possible to give a rough estimate of how much weight a man weighing 94 kg could lose after 100 hours of water fasting.
First, it's important to note that approximately 70-80% of your weight loss will be water loss. The remaining 20-30% will be fat loss.
So, let's say a man loses 5% of his body weight during a 100-hour fast. This means he will lose about 4.7 kg (94 kg x 0.05 = 4.7 kg). Of that 4.7 kg, about 3.3 kg will be water loss, and the remaining 1.4 kg will be fat loss.
Of course, this is just a rough estimate. Some people may lose more weight, while others may lose less.
More information:
- It is important to remember that water fasting is not suitable for everyone. If you have any medical conditions, you should consult your doctor before fasting.
- Water fasting can be dangerous if not done correctly. It is important to be aware of the risks and precautions.
- After fasting, it is important to gradually resume eating to avoid any health problems.
Disclaimer: This information is for educational purposes only and is not intended as medical advice. Always consult a qualified healthcare professional if you have any questions or concerns about your health.
