Man tries 'world's most extreme diet' for 100 hours and reveals shocking impact it had on his body

A man who tried the 'world's most extreme diet' for 100 hours has revealed the shocking impact it had on his body.

Will Tennyson has shot to YouTube fame with more than three million subscribers for the fitness fanatic's hot takes on exercise, lifestyle and extreme challenges.

The bodybuilder and cookbook author is renowned for pushing his body to its physical limits and in May last month revealed he tested out the world's 'most extreme diet' for more than four days.

"It's time to torture every last ounce of fat off my body," Will said as he kicked-off the challenge. "This is going to suck."

"I have a feeling that I'm going to be so flat that I'm going to be two dimensional by the end of this."

The YouTuber said he felt like a 'string bean' in the challenge (Will Tennyson/YouTube)

Will revealed he followed the 'depletion' diet with a goal to starve the body of glycogen so he can fill the muscles 'even more' at the end of the challenge.

He followed a strict diet comprised of 235g of protein, 54g of carbs and 81g of fat, which basically saw him chow down on a basic meal plan of broccoli (or other green veg), chicken and one table spoon of olive oil and one quarter teaspoon of salt, three times a day, plus a protein powder shake of two scoops.

"I think the last time I had 54g of carbs in a day was the day I stopped breastfeeding. That is practically keto," Will remarked at the start of his journey.

He also had four rules: to walk 12,000 steps every day (outside of exercise), drink two gallons of water, and avoid artificial sweeteners or any additional seasonings beyond his salt and olive oil allowance.

Will started with a weigh in of 178.3lbs and throughout the course of the next few days, suffered some side effects from the extremely restrictive diet.

His coach said the depletion diet is 'brutal' for hunger, and Will himself showed that even by day one, his energy had taken a beating.

All while still regularly working out at the gym, he said: "Training during a depletion is like Olympic diving into a frozen laze. They just don't go together."

He also told his viewers how he tried to maintain positive, but commented things like: "This diet is like a freaking arranged marriage because the only passion that I have is the desire to cheat on it.

"I did not think that I would get sick of this on day one."

After the first night, he said he went to bed 'starving' and wanting to 'cry'.

"I feel really weird right now like my head is pounding," he added.

The meals became a struggle (Will Tennyson/YouTube)

By the next day, he had already lost 3lbs and said it was even more of a struggle, commenting how he felt like a 'string bean'.

It wasn't just feeling tired or the hunger that bothered him, but the fact he felt 'extremely weak'.

"My body feels like it's shutting down," Will added.

"On the bright side I'm no longer afraid of zombies, because I am one."

Again by bedtime and after another day of chicken, veg, olive oil, a sprinkle of salt and protein powder, he said his head was hurting and he felt 'extremely moody'.

"I had to close the blinds, the sun hurts my head. I can't watch TV because the TV hurts my head," he remarked. "If I stand up I'm going to fall over."

Will before and after the extreme diet (Will Tennyson/YouTube)

By the time his challenge came to an end, Will's physique presented a drastic change.

He revealed he weighed 173.8lbs - a big drop with a weight loss of 4.5lbs in just four days.

"I definitely see a huge difference especially in my quads. They sharpened up a lot, I do look a lot flatter," he said.

However, needless to say he was glad the challenge was over and he could finally eat carbs (especially a sweet potato) adding that his muscles had become so achey he couldn't 'connect' with them at all.

Ouch!