Meal replacement drink Soylent will launch in the UK on Thursday with a different formula to its US equivalent.

The firm has replaced seven ingredients and adjusted the mineral and vitamin content to comply with British regulations.

Soylent was withdrawn from Canada in 2017 after the Food Inspection Agency found it did not meet their standards for "meal replacement".

The firm said it was working with Canadian authorities to reinstate it.

A food bar version was also recalled in the country in 2016 following reports that it made some people ill.

The Silicon Valley start-up became the largest crowd-funded food project when it launched in the US in 2013.

It was marketed at busy professionals and the company originally suggested the product could replace meals regularly.

It is named after a fictional artificial food called soylent that was featured in the 1966 sci-fi novel "Make Room! Make Room!".

In the 1973 movie version - Soylent Green - it was revealed that soylent was made from dead people.

'Food void'
However the firm has now rebranded it as a more occasional meal, to replace what it calls "food voids" - times when a conventional meal is not possible because of time, logistics or money.

CNN Anchor Anderson Cooper recently revealed that he was trying to replace all of his meals with Soylent drinks.

Soylent chief executive Bryan Crowley said he had faced criticism from nutritionists about the product.

"Nutritionists have a tough job, their usual response is we would rather they eat fruit and veg," he told the BBC.

"But we've been saying that for years and it isn't working.

"We're not trying to replace the meals you have with family and friends, weekend brunch - we're not trying to compete in that area. What we're saying is, we cant change how busy you are but we can provide you something nutritious to consume when you are that busy."

What does it taste like?
If you like your drinks to taste slightly chalky with a hint of porridge then this could well be a lunch option for you.

The main ingredient - after water - is genetically modified soya protein, so the drink unsurprisingly tastes like a protein shake from the gym.

Of the three launch flavours - original, cacao and cafe mocha - cacao is probably the most recognisable as it's a bit like a chocolate milkshake... if you try not to think about it too much.

Does it fill you up? It did for a bit. At 400 calories per drink, it's a bit heavy to be classed as a snack, but my liquid lunch companion was running for the nearest sandwich bar after two hours and while I've resisted that temptation, I'm not sure I could face another one for dinner.

Competition
It is Soylent's first foray into Europe but it already faces competition from others such as Huel, a UK-based product that launched in 2015.

Kris Ringer replaces two meals per day with Huel and said he felt the balance of his diet had improved.

"I don't think I could go to a full replacement though - by the end of the day I'm longing for real food that I can actually chew," he said.

"I'm quite happy with Huel so don't think I'd make a switch [to Soylent] unless it turned out to be as effective and cost less."

Soylent will be sold in ready-to-drink form via Amazon, retailing at £39.99 ($52) for 12 bottles.

The minimum order of Huel powder is sold online for £50 and provides 28 meals.

Bryan Crowley said that having competition was healthy.

"People ask me about competition - we have the advantage that we are the original," he said.

"This was founded five years ago on the crazy concept of a life food hack. It started to create a movement, and to build any new behaviour you need a lot of brands coming on board and raising awareness."

'Food is key'
Dietician Priya Tew said meal replacements can be useful but should not be relied upon.

"Eating whole food is always better when possible as there is an element to the chewing and digestion process that is important to our systems and psychologically food is key for us too," she told the BBC.

"Food is a package of nutrients many of which we are not even aware of. Things like antioxidants and phytochemicals will not all be in the meal replacements, so eating a range of colourful food is the best way to nourish our bodies long term."