Three and a half days. No food. Just water, electrolytes, and pure determination.

I recently completed my first ever 86-hour fast, and I can honestly say it changed me.

Not just physically — though the physical benefits were incredible — but mentally and emotionally too. I feel lighter, sharper, more connected to myself.

In a strange way, it feels like a fog I didn’t even know I was carrying has finally lifted.

The first day tested me. Hunger came in waves, doubt crept in, and I questioned why I was doing this.

But as the hours passed, my body adapted. Hunger faded. My mind cleared. My energy returned stronger and steadier than before.

What started as a simple health experiment quickly became something deeper — a reset, a cleansing, a reclaiming of control over my own body.

By the end of 86 hours, I wasn’t just fasting — I was thriving. Clear, energized, and profoundly grateful for the experience.

In this post, I’ll share why people commonly fast, and why stepping into discomfort for a few days might just be one of the most rewarding things you ever do.

Why Fast?

An 86-hour fast is an intense form of fasting that is typically done for various health, wellness, and performance reasons. 

People engage in long fasts for a variety of reasons, each based on different health goals or personal beliefs. 

1. Fat Loss and Metabolic Benefits

• Enhanced Fat Burning: When you fast for 86 hours, your body depletes its glycogen stores and shifts to burning fat for energy, leading to significant fat loss. Since fat is the primary energy source after glycogen is used up, prolonged fasting increases lipolysis (fat breakdown) and ketosis, which accelerates fat burning.

• Improved Insulin Sensitivity: Fasting helps to lower insulin levels and improve insulin sensitivity, which can support better metabolism and reduce the risk of developing insulin resistance, type 2 diabetes, and metabolic syndrome.

2. Autophagy and Cellular Repair

• Autophagy Activation: Autophagy is the body’s natural process of cleaning out damaged cells and regenerating new, healthy ones. When you fast, your body starts to break down and recycle dysfunctional proteins, which helps improve cellular function and repair. 86-hour fasts are often used as a way to maximise this process.

• Anti-Aging and Longevity: By promoting autophagy, fasting has been shown to enhance cellular repair and might even help slow down the aging process. Many studies suggest that autophagy plays a crucial role in preventing diseases associated with aging, such as cancer, Alzheimer’s, and heart disease.

3. Mental Clarity and Focus

• Increased Mental Clarity: Some people report improved focus, mental clarity, and cognitive function during extended fasts. This is often attributed to the production of ketones (a byproduct of fat burning) which are used by the brain as a clean and efficient fuel source during fasting.

• Improved Brain Function: Fasting may stimulate the production of brain-derived neurotrophic factor (BDNF), a protein that supports brain health, enhances memory, and increases neurogenesis (the formation of new neurons).

4. Hormonal Health and Growth

• Increased Human Growth Hormone (HGH): During a fast, your body increases the secretion of HGH, which is essential for muscle growth, fat loss, and overall vitality. Fasting for 48-72 hours can significantly elevate HGH levels, which is why it is often utilised by those looking to improve body composition.

• Improved Hormonal Balance: Fasting can help balance various hormones that control appetite and metabolism, such as ghrelin (hunger hormone) and leptin (satiety hormone). Over time, fasting may also reduce inflammation and support hormone regulation in a positive way.

5. Detoxification and Gut Health

• Detoxification: During a prolonged fast, the body can expel toxins that have accumulated in the liver, kidneys, and other organs. This is especially beneficial in cases of heavy metal exposure, inflammation, or other forms of toxicity that can accumulate over time.

• Gut Rest and Healing: Fasting provides the gut with a rest period, allowing it to repair and regenerate. For individuals with conditions like leaky gut or IBS, a 86-hour fast can help reduce inflammation in the digestive system and reset gut microbiota.

6. Potential Disease Prevention

• Reducing Inflammation: Extended fasting can significantly lower inflammation in the body, which is a root cause of many chronic diseases like heart disease, arthritis, and autoimmune disorders. By reducing inflammation, fasting may help prevent the progression of these conditions.

• Cancer Research: While more research is needed, some studies suggest that fasting could have potential benefits in cancer prevention. The theory is that fasting can make cancer cells more vulnerable to chemotherapy and radiation, potentially slowing tumour growth. However, this is an area of ongoing study and should not be considered a treatment in itself.

7. Spiritual and Mental Clarity

• Spiritual Growth: Many cultures and religions incorporate fasting as a way to promote spiritual growth, self-discipline, and mindfulness. Extended fasting can be a way to practice self-control, deepen one’s meditation practice, or engage in personal reflection.

• Mindfulness and Discipline: Fasting often challenges individuals both physically and mentally. Completing an 86-hour fast can promote resilience, mental strength, and mindfulness, giving participants a sense of accomplishment.

8. Resetting Eating Habits

• Breaking Cravings: An 86-hour fast can help break unhealthy eating patterns, especially those linked to sugar addiction or overeating. It helps reset the body’s relationship with food, potentially leading to healthier eating habits once the fast is broken.

• Improved Appetite Regulation: After fasting, many individuals find they have a more controlled and mindful relationship with food, as fasting helps reduce cravings and resets hunger signals.

Risks and Considerations:

While an 86-hour fast can have powerful benefits, it is not suitable for everyone. It is essential to consider potential risks, especially for those with pre-existing medical conditions, such as diabetes, eating disorders, or heart conditions. It is always recommended to consult with a healthcare provider before attempting a fast of this length.

Common risks include:

• Fatigue and weakness in the initial phase of fasting.

• Dizziness, irritability, and mood swings due to fluctuating blood sugar levels.

• Nutrient deficiencies if not done correctly or if fasting is prolonged too frequently.

• Digestive discomfort upon refeeding, if not done carefully.

In Summary:

An 86-hour fast can serve a variety of purposes, including accelerating fat loss, promoting autophagy and cellular repair, enhancing mental clarity, improving metabolic health, and even supporting spiritual growth.

However, it should be approached with care and planning, as it can be intense and is not suitable for everyone.

The potential benefits are compelling for those who are healthy and well-prepared, but the risks should always be considered.

Respect the fast. Respect yourself.

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