When 24-year-old software developer Rob Rhinehart stopped by Gawker's office last Wednesday afternoon he hadn't had a bite of solid food in four days, but was brimming with energy. Some of his pep was probably due to the fact that the previous day he launched a hugely successful crowd-funding campaign for Soylent, the liquid food replacement he invented and largely subsists on. It had received over $200,000 in a matter of hours. But the rest, he'd say, was science.

Rhinehart rattled off the benefits he's noticed since switching almost exclusively to a diet of Soylent: improved concentration and strength, weight loss. "By every objective measure, I'm an incredibly healthy person," he said. "It's been a huge change, not just in terms of sleep and gym performance but cognition. I can say I feel much more alert, and more patient, and optimistic."

Rhinehart had brought along liter Soylent for a Gawker taste test. Soylent is a slurry of vitamins, minerals, protein, and carbohydrates that Rhinehart concocted in his kitchen and now believes is the of future food. In a February blog post announcing the Soylent "experiment," called "How I Stopped Eating Food," Rhinehart explained:

I researched every substance the body needs to survive, plus a few extras shown to be beneficial, and purchased all of them in nearly raw chemical form from a variety of sources… The first morning my kitchen looked more like a chemistry lab than a cookery, but I eventually ended up with an thick, odorless, beige liquid. I call it 'Soylent'.

Since then, Rhinehart says he's fine-tuned the formula using himself and a half-dozen volunteers as human guinea pigs. Dozens, if not hundreds, more, have followed or modified Rhinehart open source recipe and shared their experiences on Soylent's active forums.

Soylent inventor Rob Rhinehart.

Rhinehart took a one-liter Nalgene bottle full of Soylent out of his messenger bag. Each liter of Soylent contains approximately 1,000 calories, according to Rhinehart. He drinks two and a half liters per day. Contributors to the crowdfunding campaign can purchase a month's supply of Soylent for $230, or about $7.60 a day, but ultimately Rhinehart hopes an all-Soylent diet will only cost $5/day.

I was pretty full from the half pound of lasagna I'd just eaten hours earlier for lunch, but I poured myself a tall glass. Soylent looks as appetizing as it sounds. The combination of its off-white color, opacity and viscosity made it look—sorry to be gross here—like watered-down semen. Tiny specs of something brown and no doubt highly nutritious floated in the liquid. Taking a sip, it was actually not distasteful, as long as I blocked out all thoughts of bodily fluid. (This was hard to do; perhaps Soylent could improve my ability to concentrate on things other than semen while drinking Soylent.) Soylent tastes like the homemade nontoxic Play-Doh you made, and sometimes ate, as a kid. Slightly sweet and earthy with a strong yeasty aftertaste.

Gawker staff tried Soylent. Feedback was mixed. Including:

  • "[It] made me feel like joining a cult, after just one sip."
  • "It tasted like when you're baking and you taste the ingredients even if there's not sugar or vanilla in there, you just have a compulsion to taste wet food."
  • "My mouth tastes hot and like old cheese."
  • "It tasted like someone wrung out a dishtowel into a glass."
  • "It was great and I love it. I don't want to eat anymore."

We may have focused too much on the taste, which Rhinehart says is beside the point. "I'm not trying to make something delicious; there are already a lot of delicious things," he said. "It's all about efficiency, it's about cost and convenience." Rhinehart said he used to spend many hours a day buying and preparing food that was nowhere as near nutritious as the Soylent he makes in a minute by adding the powdered nutrients to water. Now, "I don't have to cook, I don't have to clean dishes."

There are of course plenty of other health shakes, nutrition supplemnts, juice cleanses, energy drinks etc. But what makes Soylent unique, is that it is the first of these "functional beverage" developed for and by young, male tech geeks. The new company founded to bring Soylent to market is based in Silicon Valley, and most of its founders met while launching a wireless communications start-up as part of the famed tech company incubator Y Combinator. Now, they're making Soylent.

"Paul Graham called it the 'pivot of the century,'" Rhinehart said, referring to the Y Combinator founder and venture capitalist. Soylent has been a much-discussed topic on Hacker News, the preeminent digital water cooler of the tech industry.

These are people who believe every moment they don't spend coding a world-changing app might be a loss for humanity. So feeding yourself is a time-wasting problem that can be solved with technology. Soylent is part of the geek "biohacking" movement, which seeks to improve body function through obsessive self-tracking and chemical substances. Some critics have said Soylent is just an extreme weight-loss diet in disguise, but I believe Rheinhart when he says his only goal is cold, hard efficiency: the maximum nutrition with the minimum effort. When Rhinehart finished his third month of Soylent in April, he noticed his farts stopped smelling. More disconcertingly, his joints began to ache. He self-diagnosed a sulphur deficiency. "Ten grams of sulfur from Methylsulfonylmethane cured me right away," he wrote. Rhinehart had debugged himself.

Soylent has become a big internet story, thanks to Rhinehart's savvy marketing campaign and crowdfunding windfall. There are a surprising amount of people on the internet who want to live on thick odorless beige liquid, and Rhinehart—intense, nerdy, blithely optimistic—is the perfect guy to speak to them. Currently, Soylent's crowdfunding campaign has raised over $340,000 and it still has 23 days left. Still, Soylent is controversial. A number of nutritionists have come out agains the idea that anyone can live on goop alone. (Rhinehart counters that he doesn't intend Soylent to replace all food in one's diet—just most.) Others have pointed out that liquid food replacement already exists in a much less sexy, medical form: It's the same stuff being forced down the throats of the Guantanamo Bay hunger-strikers.

Rhinehart brushes off the haters as luddites: "Food is a haven for reactionaries," he wrote. "In the past food was about survival. Now we can try to create something ideal."

After Rhinehart left, I still had half a pint of Soylent in my glass. Rhinehart says Soylent is best chilled, but mine was lukewarm and a brown sediment had settled at the bottom of the glass. I was having trouble getting it down. I tried imagining subsisting on Soylent. A jug of Soylent omnipresent at my side, silently replenishing myself during meetings or a movie. It seemed gothically futuristic: The tragic fate of someone with a rare chronic disease caused by radiation expsourein the post-apocalypse.

But then, couldn't hunger be seen as a sort of chronic condition? And food the medicine you treat it with? Imagine if the only way to treat some disease was to buy many different ingredients from a store, then cook the ingredients into medicine according to a complicated recipe, then clean up all the equipment after. Wouldn't you want a simpler medicine, something you could just chug? I was beginning to see the logic that led to Soylent. Then I took another big gulp of the stuff and my feeble, lasagna-fired mind faltered and I thought of bodily fluids and began to gag, so I dumped the whole thing in the sink.