After completing a full 86-hour fast, I can honestly say: I feel like a new man.

When I first set out to do this, I wasn’t sure what to expect.

Would I be starving the whole time? Would I feel weak, tired, irritable? Honestly, part of me wondered if I could even make it to the finish line. 

But what unfolded over those three and a half days was something I didn’t fully anticipate — a complete reset not just for my body, but for my mind as well.

Originally, I just wanted to do a 72 hour fast, but after seeing a video from UFC president Dana White on the benefits of an 86 hour fast, I set my targets a bit higher.

The reason I wanted to do such an apparently extreme fast was to reset some eating patterns, exercise my willpower and discipline, and achieve something called autophagy, more on that soon.

The first 24 hours were a challenge — my body fought to hold on to its old habits.

But after I pushed through the initial hunger waves, something incredible happened. My mind sharpened. My energy levelled out.

My body felt lighter, cleaner, more alive. It was as if years of stress, bad eating, and built-up inflammation were being washed away, layer by layer.

By the end of the 86 hours, I wasn’t just surviving — I was thriving. Clear-headed. Focused. Empowered.

It wasn’t just a physical detox; it was a mental and emotional one too.

In this blog, I’m going to walk you through exactly how I accomplish it — and why you might want to try it yourself.

Intro

Fasting for 86 hours might sound intimidating at first — but if you approach it correctly, it can be a powerful reset for your body, mind, and spirit.

Whether you’re aiming for fat loss, better mental clarity, or deep healing, an 86 hour fast taps into some of your body’s most profound survival mechanisms.

In this guide, I’ll walk you through exactly how to prepare, what to expect during each phase, and how to break your fast safely.

The Dana White Video:

After seeing this video and hearing that just 1 prolonged fast can eliminate your chances of all morbidity by up to 70%, I knew this had to be done!

Short Autophagy Explanation Video:

Note: Dana White used Bone Broth during his fast, I did not, I only used electrolytes. My research showed that any amount of calories can kick you out of the autophagy phase, so I chose to abstain and break my fast with bone broth instead, as autophagy was one of my main motivation for fasting.

Why Fast for 86 Hours?

Prolonged fasting shifts from burning sugar to burning fat and ramps up autophagy (the cleanup and recycling of old cells), boosts your growth hormone, and starts deep cellular repair. 

Fasting also resets your immune system, reduces inflammation, and can enhance longevity.

Here are just a few scientifically-backed benefits:

• Deep cellular repair (autophagy)

• Fat loss and improved metabolic health

• Mental clarity and mood enhancement

• Reduced inflammation

• Strengthened immune system

• Potential anti-aging effects

How to Prepare (Day Before the Fast)

Proper preparation makes all the difference between a miserable fast and a successful, empowering experience.

There are some key items you need to have before you attempt this length of fast, electrolytes being probably the most important!

I cannot stress how important it is to have electrolytes in the cupboard.

I attempted a long fast 3 weeks prior, and had to abandon the fast after 56 hours due to headaches.

Before you start, make sure you have in some electrolyte powder, the one I use is this one:

The Electrolytes Available Here:

https://theketopro.com/collections/electrolytes/products/keto-electrolytes?variant=40325926191272

Break Your Fast with Bone Broth:

Bone Broth Available Here:

https://boroughbroth.co.uk/collections/all

I bought in a 10 pack of these broths and froze them - take one out the freezer 24 hours before you break your fast, heat up & drink - they are wonderful!!

I can also recommend a good yogurt to break you fast if you can tolerate it, I luckily can tolerate Lactose so the one I recommend is Rora Dairy - it is packed full of Live Cultures, protein & fat & easy on the gut (for me anyway, everyone's different).

Just 4/5 spoonfuls is enough to start, your digestive system has been unused for days so re-feeding should be done mindfully. 

P.s. Don't add honey or granola. Your insulin sensitivity has increased due to the fast, anything too sweet will spike it.

Yogurt available at Asda.

The Day Before:

• Eat a low-carb, high-fat meal: Think salmon, avocado, leafy greens, olive oil. This helps deplete glycogen stores and transition into fat-burning faster.

• Hydrate thoroughly: Aim for 3+ litres of water.

• Cut out sugar and alcohol: These spike insulin and make fasting harder.

• Mental prep: Set your “why” — your intention behind the fast. Mindset matters!

Optional: Gradually reduce food intake (smaller meals) 12–24 hours before starting.

86-Hour Fast Plan

Day 0 (Sunday) — Pre-Fast Prep

• Last meal by 7:30 PM, fast begins at 8 PM.

• High-fat, moderate-protein, low-carb meal to ease transition to ketosis.

• Hydrate well (electrolytes, water).

• Avoid sugar, alcohol, and refined carbs in the 24 hours prior.

 

Day 1 (Monday) — Hours 0–24

• Fasting Hours: 0–24

• State: Glucose still in circulation; insulin levels drop.

• Body: Begins glycogen depletion (mainly liver stores).

• Energy: May feel hunger, mood swings, or fatigue.

What to do:

• Drink water

• Take electrolytes (sodium, potassium, magnesium).

• Light exercise (walking, yoga).

• Rest if needed, especially in the afternoon.

What You Might Feel:

• Hunger waves (strong but usually short-lived)

• Mild fatigue

• Possible cravings, especially in the evening

Tips:

• Stay hydrated: Water, black coffee, herbal teas allowed.

• Salt your water: Add a pinch of Himalayan salt to prevent electrolyte imbalance.

• Stay busy: Gentle walks, light work, reading — distraction is your friend.

 

Day 2 (Tuesday) — Hours 24–48

• Fasting Hours: 24–48

• State: Ketosis begins; liver produces ketones.

• Autophagy is active.

• Energy: Mental fog may clear, body starts using fat for energy.

What to do:

• Continue electrolytes daily (add pink salt or electrolyte powders).

• Stay hydrated (at least 2–3 litres of water).

• Light activity only—your body is switching fuel sources.

What You Might Feel:

• Reduced hunger (surprisingly!)

• Mental fog lifting

• Mild “keto flu” (headache, irritability, dizziness if electrolytes drop)

Optional support:

• Apple cider vinegar in water (1 tbsp in 8 oz) to ease nausea or aid digestion.

• Herbal teas (ginger, peppermint).

 

Day 3 (Wednesday) — Hours 48–72

• Fasting Hours: 48–72

• State: Deep ketosis and peak autophagy.

• Energy: May feel euphoric or laser-focused.

• Body: Maximum cellular cleanup, fat oxidation is high.

What to do:

• Avoid overexertion but enjoy the clarity—this is the “sweet spot.”

• Meditate, journal, reflect.

• Prioritise hydration and sleep.

• Continue electrolytes 2–3x/day.

What You Might Feel:

• Mental clarity, almost euphoric focus

• Very low hunger

• Calm, steady energy

• Some may feel chilly — normal as metabolism shifts

Tips:

• Stay gentle: no heavy exercise.

• Continue drinking plenty of fluids.

• Enjoy the deep, clean feeling your body is producing!

 

Day 4 (Thursday) — Hours 72–86

• Fasting Hours: 72–86

• State: Autophagy may plateau but remains active.

• Energy: You may feel clear-headed or mildly tired.

What to do:

• Prepare for re-feeding—this is critical.

• Buy or prep a gentle re-feed meal (see below).

• Light stretching or walking is ideal.

How to Break Your Fast (VERY Important)

The first thing you eat after your fast matters immensely.

If you overload your system with a big meal right away, you risk shocking your gut, causing bloating, cramping, nausea, or even a dangerous condition called refeeding syndrome (rare but serious).

Also, be prepared to fall in love with food again, I'm sure my tastebuds were reset as everything was waaay nicer than I remembered!!!

Breaking Fast Safely:

Re-feed Meal Plan (First Meal):

• Small portion, chew slowly, stop at first sign of fullness.

Good options:

• Bone broth (great first intake).

• Yogurt or Light protein (eggs, chicken breast).

• Cooked veggies (zucchini, spinach).

• Small serving of avocado or olive oil for fat - I made a home made Guacamole and it was 'out of this world' good!

Start with something simple and easy-to-digest:

• Bone broth

• A few slices of cucumber

• Small handful of berries

After 1–2 hours, have a light meal:

• Steamed vegetables

• Lightly cooked fish or eggs

Avoid:

• Heavy carbs (bread, pasta)

• Sugary foods

• Alcohol

• Fried or greasy meals

Eat slowly and listen to your body.

Electrolyte Water Recipe (Lifesaver!)

Electrolytes are soo important, so make sure you buy some Electrolyte Powder in, or here’s a simple electrolyte drink you can make to sip throughout your fast:

DIY Electrolyte Drink:

• 1 litre of water

• 1/4 tsp pink Himalayan salt

• 1/4 tsp potassium chloride 

• 1/4 tsp magnesium citrate (optional)

• A squeeze of lemon (optional for flavour)

Drink 1–2 litres daily, especially if you feel dizzy, tired, or get cramps.

Common Mistakes During a 86-Hour Fast

• Not supplementing electrolytes — biggest cause of “keto flu”

• Breaking the fast with a huge or junk meal

• Doing intense exercise — gentle movement is better

• Obsessing over the clock — stay busy instead

• Ignoring signs of severe weakness — if you feel faint, break the fast safely

Extra Tips for Success

• Electrolytes are critical: Sodium, potassium, magnesium.

• Sleep well: Your body needs time to repair.

• Gentle movement: Walks, yoga, stretching.

• Mindset: Fasting is natural — your body knows what to do!

Final Thoughts

An 86-hour fast can be transformational if done mindfully.

It’s not just about abstaining from food — it’s a profound physical and mental reset.

Stay hydrated, stay calm, listen to your body, and treat the fast as an act of healing, not punishment. 

If you need to break it early because of severe symptoms, there’s no shame.

Even 24–48 hours can provide massive benefits.

I for 1 will be implementing fasting into my life going forward much more, and I am planning on perhaps 2x 48 hour fasts per month.

Respect the fast. Respect yourself.

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