What mechanism can you imagine that would produce such a nightmare scenario? Is there a fat-soluble (or otherwise stored) nutrient of which most human bodies contain a five to ten year supply?

No I didn't think so. If Soylent Dude and his merry band of poor cooks can prove our current nutritional understanding wrong by dying five to ten years from now, then they should.

As mentioned, there are too many "unknown unknowns" to say for sure. So I'll refer to an anecdote:

http://www.psychologytoday.com/blog/animals-and-us/201106/wh...

In her early 30's, Staci's health started going downhill. After twelve years of strict vegetarianism, she began to suffer from anemia and chronic fatigue syndrome, and she experienced stomach pains for two hours after every meal. "I was completely debilitated," she tells me. "Then I changed the way I ate."

The point here is not to bash vegetarianism, but to point out that it took her 12 years to develop health issues. And that's with vegetarianism, that is often considered a very healthy way to eat. So I would expect more potential hazards from something new, untried and untested.

From that study, about 20% of vegetarians who go back to eating flesh do so for perceived health reasons.

After 12 years of no health issues, and with a low general reason to believe that vegetarianism causes health issues, I'd be slow to attribute the reversal to the thing the person thinks worked.

(I would also expect more potential hazards from something new, untried, and untested, but I've signed up because I like the idea and am willing to risk it. Fortune favors the bold.)

Just to clarify - that was an example. Whatever will be wrong with Soylent, will probably be something no one considered.

What do we know about completely eliminating fiber from the diet for an extended period of time? Or what do we know about chewing food being beneficial for dental health? It was mentioned he hardly poops on Soylent - were there prolonged studies on this subject?

Willingness to risk is something I respect, anyway.

The diet of the Inuit was widely believed to be impossible for some time (and probably still is) because no one thought it was possible they could subsist solely on fish meat.

When put to the test by a pair of scientists who replicated the diet though, they found few ill-effects - except at one point where they were hitting a nutritional deficiency, but corrected it by putting semi-rotten fish product (which is a dish in Inuit cooking) into their diet - because it turns out that provided certain key nutrients.

The human body can handle some surprising and varied diets, a lot simply evolved by trial and error over a long period. With modern technology, we should be able to "fail fast" over a much shorter time.

Probably more importantly: anyone putting that much thought into what they eat, what the effects of it are etc. is already doing 10x the thinking of most people about their nutrition.

I would like to know more ...

I know a bit about Inuit and their diet - I've read "My Life with the Eskimo" by Vilhjalmur Stefansson

http://www.amazon.com/Life-Eskimo-New-Vilhjalmur-Stefansson/...

Stefansson and another explorer, Andersson, participated in an experiment where they did not eat anything but meat for a year - and remained in excellent health

http://inhumanexperiment.blogspot.com.au/2009/09/two-brave-m...

But I haven't heard about the 'rotten fish' and specific nutrients that can be obtained from it ...

I don't know about the Inuit, but "gravad" fish (fish buried and fermented near the tide mark) has been fairly common in the Nordic countries as well as in the Baltics since the middle ages or before.

"Rakfisk", a Norwegian variation, could be left to ferment up to a year. Iceland has Hákarl, - fermented Greenland shark that is also left for 6-12 months: "http://en.wikipedia.org/wiki/H%C3%A1karl containing ammonia (the process is used because it is poisonous when fresh).

My total guess is that it's more about having access to a wider range of types of food throughout the winter, when many other dietary choices disappear. Traditional food in the Nordic countries at least is very centered around processing that allows for longer term storage, and I'd guess Greenland has much the same.

That second link should be the experiment I was referring to. I remember reading an account of it that one of them did run into some vitamin deficiencies which they realized were because they'd been excluding a particular type of partially-rotten fish dish that normally provided them.

>The point here is not to bash vegetarianism, but to point out that it took her 12 years to develop health issues.

No, it took her twelve years to admit to and respond to health issues. They presented very early on. She was simply on a terrible diet, and was deficient in iron. No mystery, no "unknown unknowns", just a very simple, straightforward, common deficiency we've known about for decades.

Are you kidding?

It's not about your body suddenly running out of a nutrient five years down the line. It's about your body starting to repair and build structures that need to last for years while missing key ingredients.

As a random example, people can develop osteoporosis after years of drinking diet soda.

> As a random example, people can develop osteoporosis after years of drinking diet soda.

citation?

You don't your side of the argument any favours by offering made up nonsense like "aspartame causes osteoporosis" as an example.

He'll probably have it but I believe vitamin B12 can last for 5 years, so there may be others.