Okay, not literally; but in the traditional sense of the word -- chewing and swallowing solid foods -- he did.
Inspired by science fiction movies like The Matrix and Soylent Green, Rhinehart concocted a beige, milkshake-like substance that he calls Soylent. (For those aware of the film Soylent Green, don't worry, Rhinehart's drink is not made of humans.) It's now just about the only thing he consumes. Speaking about his futuristic and gloppy creation, Rhinehart echoes the words of Dozer from The Matrix: "It contains everything the body needs." Water, vitamins, minerals, proteins, carbohydrates, fat. It's got it all.
"I hypothesized that the body doesn't need food itself, merely the chemicals and elements it contains," Rhinehart wrote on his blog. "So, I resolved to embark on an experiment. What if I consumed only the raw ingredients the body uses for energy?"
To fabricate Soylent, Rhinehart basically turned his kitchen into a chemistry lab. He procured many of the ingredients -- like raw vitamins and minerals -- from nutrition lab supply stores. The bulk of the drink's calories come from maltodextrin, a long-chained carbohydrate that's broken down gradually by the body. Whey protein isolates provide protein, and olive oil supplies fat. The amounts of nutrients and macronutrients contained in the drink are roughly based on the Institute of Medicine's (IOM's) reference daily intakes (pdf).
Let's Get Skeptical
Nutritionally, Soylent seems scientifically sound, incorporating adequate ratios and amounts of macronutrients, vitamins, and minerals. It really does seem to cram life's essentials into a simple potion.
However, Soylent's fiber content constitutes a mere 1.2 grams per day in Rhinehart's current iteration of the drink. That is far below the IOM's recommended daily intake, which is 38 grams. As you might have guessed, Rhinehart admits that he basically doesn't poop anymore -- perhaps once a week. That may be less smelly, but that's not necessarily healthy. Regular defecation has real benefits, specifically for the colon.
Another nitpick: In Rhinehart's original blog post revealing his diet, he boasted improved mental performance, clearer skin, increased energy, speedier reflexes, and a litany of other improvements. All of that can likely be attributed to the placebo effect and the fact that he transitioned from a diet mostly devoid of healthy foods to one rich in vitamins and minerals. Additionally, he also began exercising, which features many proven benefits. Soylent certainly isn't a wonder food.
In terms of cost, one might expect Soylent to be pricey, but amazingly, it's just the opposite. Consuming 2,629 calories per day of the stuff, Rhinehart spends a mere $154.82 per month. That's almost four times less than what the average American spends on food! Buying in bulk could drop prices even further, Rhinehart estimates.
What's the Big Deal?
I personally don't share Rhinehart's animosity toward eating, so I won't be trying Soylent myself. However, I am thoroughly fascinated by the idea. Rhinehart has transformed eating from a time-consuming activity to a measured, scientific venture -- a numbers game. Breakfast, lunch, and dinner are now functions of a self-experiment. Based on the results of this examination, one can precisely adjust Soylent to their liking. Want to lose weight? Simply lower your serving sizes. Want to try a higher protein diet? Add more whey. Want to invigorate your gut flora? Insert a probiotic.
Typical food -- from spaghetti to burgers to bananas -- is nothing but atoms and molecules bonded together in various ways. When chewed and digested, our body breaks them apart and absorbs them for fuel. Rhinehart has merely simplified food to a highly nutritious glop that satisfies the body's basic dietary needs.
Nutritionists can debate the merits and flaws of Rhinehart's creation, but the simple fact is that it is feasible. Over two months of eating Soylent for over 90% of his meals, Rhinehart's health has remained remarkably consistent, as evidenced by his blood work. (Start, 1 Month, 2 Month (pdfs)). Physically, he has dropped about ten pounds and is now maintaining weight between 190 and 195lbs, which is normal for Rhinehart's height (6'3").
Rhinehart says that Soylent isn't a miracle diet, and occasionally, he still eats regular food with friends and family.
So, whether somebody could survive on Soylent alone is not in question. They could. The real question is: Would anyone want to?
(Image: Food Powder via Shutterstock)