"If there was a way that I could not eat, so I could work more, I would not eat. I wish there was a way to get nutrients without sitting down for a meal" - Elon Musk.

I might not be a billionaire polymath but one thing I do have in common with Elon Musk is wondering whether it will ever be possible to never have to eat again. It used to be a staple of science fiction that a single pill could replace an entire meal, and while we still might not be at the level of the Jetsons, three startups have taken it upon themselves to reinvent the way we think about food.

Finnish startup Ambronite, UK-based Huel, and Silicon Valley's Soylent have developed what they variously describe as "the future of food", "a drinkable supermeal" and "a food revolution".

What each product essentially consists of is a powder that contains all of the nutrients your body needs. Mix it with water and you have a meal.

"The whole idea is that one Ambronite contains a quarter of the daily guidelines for the average diet, which is 2,000kcal," Ambronite co-founder Simo Suoheimo told IBTimes UK.

"It's to give you a superior alternative to anything else that's out there, that you'll have no trouble using - whether you're at the office or sailing the Atlantic."

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Future of food stats: How does Ambronite compare to rivals Huel and Soylent?IBTimes UK

Suoheimo was referring to Ari Huusela, who last year completed a solo race across the Atlantic Ocean surviving partly on Ambronite. Although I had no plans to sail the Atlantic any time soon, I asked Suoheimo to send me a week's worth of Ambronite to put his bold claims to the test.

After one final fry up to line my stomach, I set about a seven-day challenge to replace all my meals with Ambronite.

One week living on Ambronite

Day one (weight: 73.1kg) - Ambronite's key selling point is that, unlike Soylent and Huel, it uses 100% organic food ingredients - including spinach and stinging nettle leaves - but this comes at a cost. It's four-times more expensive than its rivals and as a result can't be viewed as a solution to any impending global food crisis.

The natural ingredients give it a mud green colour and the texture of a melted milkshake. My first impressions of the taste was that of green tea mixed with Ready Brek, which are flavours I fortunately quite like.

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Three startups - Huel, Soylent and Ambronite - claim their pouches of powder can replace solid foodIBTimes UK

It took me an hour to drink my first meal and afterwards I didn't feel hungry, but nor did I feel full. Lunch at my desk proved to be convenient but dinner was bleak and I learnt it doesn't go well with a beer. By my own unscientific rules, throughout the week I allowed myself to drink my usual beverages of water, tea and alcohol.

Day two - After going to bed hungry the day before, I upped my intake from three pouches to four. As a cure for hunger, I found it about as satisfying as a salad. Drinking a pint of it gives a bloated feeling but it never actually makes you feel full.

Due to the time it takes to drink, I found myself with it always by my side, sipping at it all the time, whether going to work or doing some shopping.

Day three (weight 71.2kg) - Weighing myself again at lunch time I learnt that I had already lost two kilograms. With a 16-mile cycle and a game of football to play I forced five pouches down me. As a post-pub feed it proved ineffective.

What the nutritionist said

"In terms of the nutritional content [of Ambronite], it does have a very balanced nutrition profile. The concerns are more about having a liquid diet. Chewing is a really important part of digestion. It's the first part where you mix it with saliva and you mix in digestive enzymes, and if that part isn't happening then you're actually missing out on a crucial part of digestion.

"The other concern about having an all liquid diet would be it doesn't satiate you when you drink your calories. If you drink 500 calories it's not going to keep you going for as long as if you were to chew 500 calories just because of how long it takes you to actually physically break it down in your stomach.

"Having a high level of these meals would [mean] that you would have an excess of nutrients and you can end up with liver toxicity, from vitamin A especially. In terms of whether someone could eat it every day long term, or whether I would recommend that, Ambronite would probably be the best one that I've seen."

Louise Digby, director of nutrition, The Specialist Health Centre

Day four - Despite being Friday, I decided against going out and stayed home instead, sipping my dinner in the bath. I've never understood people who take pictures of their food and post them online - let alone the people who look at these pictures - but for the first time in my life I found myself browsing endless images of food. Solid food. I fell asleep with my stomach rumbling.

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Day five - Upping my intake meant upping the amount of fibre my body was consuming. Five pouches of Ambronite contains my recommended 2,500kcal, but more than twice the recommended daily allowance of fibre.

My insides were a solid tube of organic goodness. Just as consuming it had become a continuous process, so had excreting it. And this wasn't a particularly satisfying experience: like pinching off a dark green Play-Doh pipeline.

Day six - From Ambronite poo to Ambronite dreams, motes of green dust were beginning to infest every part of my life. And keyboard. For a treat in the evening I thought I'd warm it up a bit. It was surprisingly good. The "supermeal" claims were tested by a significant lack of energy. I was pretty miserable too, though both of these could be as a result of having to live off the same meal, morning, noon and night.

Day seven (72.4kg) - Just as the finishing line was in sight, it seemed to get easier. I became used to the routine, and working the late shift I even found it convenient to not have to worry about arriving home late and having to fix up dinner.

When finally it came time to eat solid food again, I gorged on pancakes and maple syrup. 10 minutes later, whether from eating too much or the sudden change of diet, I was sick.

How Huel and Soylent compare

Both Huel and Soylent come in at a significantly lower price, though my personal taste, texture and even colour choice is Ambronite. That being said, of the half dozen people who also tried all three, the preferences were evenly split.

There is a long tradition of single-diet eating challenges. Soon after Morgan Spurlock's Supersize Me documentary, two guys from Ireland decided to try their own version called Guiness-Size Me - living only off Guiness for seven days straight. More recently, Vice journalist David Allegretti made it his mission to survive on a diet of Nutella. His pictures of acid vomit make my tales of organic green poop seem rather tame.

What all of them go to show though, is that no monotonous diet is enjoyable. While Ambronite, Soylent or Huel might be useful as a breakfast, lunch or dinner on the go, they're not going to replace food any time soon.