Over generations, mice deprived of fiber permanently lost some species of gut microbes

Low-Fiber Diets Cause Waves of Extinction in the Gut

“For context, dietary guidelines recommend that (we) should respectively eat around 25 and 38 grams of fiber per day, but American adults eat just 15 daily grams on average.”

So it seems there’s a chance that the amount of fibre contained in Soylent might not be enough to sustain healthy gut flora… thoughts?


Soylent do contain fiber than what I normally eat, so soylent is healthier than my usual, but I do wonder about fiber.

Anyone has facts on how much fiber Soylent 1.5 and 2.0 has?

Do to your phrasing, it is difficult to understand what you are attempting to convey. However, I do believe you are asking for the fiber content of 1.5 (powder) and 2.0 (drink). All nutrition information is readily available on the home page if you click on “Drink” or “Powder”.

1.5 (powder) nutrition information
2.0 (drink) nutrition information

They both are listed as having 3g of dietary fiber per serving. For a 2000 kcal diet, that would be 4 servings for 1.5 (powder) and 5 servings for 2.0 (drink).

That 28-38g of fiber is based on a diet of solid food. Soylent does have fiber in it which our gut bacteria will eat. Even if some species of gut bacteria die off others will take their place. Would this be healthy?unhealthy? I have yet to see anything that describes what a “healthy” gut biome is.

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Extinction of certain species in the gut biome doesn’t necessarily mean the biome is becoming unhealthy. It just means it’s changing; adapting to a different diet. That doesn’t mean it’s good or bad, just different. What’s missing in the experiment is a test to see what happens when high fiber is reintroduced into the diet.

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That’s not actually missing, they did that and some of the taxa came back but most didn’t. Of course we knew microbiota were hereditary and that if all of a species died there’s no reason they’d come back, but the surprising result was that 3/4 of the measured bacteria taxa died off by the 4th generation low-MAC mice compared to the control high-MAC mice. That’s a huge difference in microbiome diversity, though you’re right that harm wasn’t proven I think it’s fair to say it probably was harmful.

I do think the fiber in Soylent is too low, and that RL’s reasoning of it being a liquid is insufficient. While it may still have more fiber than the standard American diet that’s not a reason to keep it where it is.


That’s what happens to the microbiome, but what about the mice themselves? What is the impact on their health?

Unless we ate them. They got there in the first place somehow.

No it’s not fair to say that without proof one way or the other. It would be like me saying it’s fair to say it probably wasn’t harmful. Maybe it was maybe it wasn’t.

Agreed. Would be better if they gave some sort of scientific proof. If they have given it I’ve missed it.


Sorry I was (and still is) quite sick. I’ll be bit more clear.

I get more fiber from Soylent from anything else I eat, so soylent is better, but then I wondered about comparison between Soylent and “average” meals. Then I wondered about how much fiber two versions of Soylent had.

Thanks. :slightly_smiling:

The great thing about gut bacteria is that (unless I’ve misunderstood things, which is quite possible) you can probably get any you’re missing by ingesting a little bit of someone else’s poop:

Yeah there has been recent research into poop transplants from healthy gut people. Especially after heavy antibiotics treatments.

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I think I’m gonna start adding psyllium husk to my soylent just in case

Close, but you’re not supposed to eat it. It gets implanted through the exit :wink:


Yikes, not sure I fancy that. I think at least some treatments involves swallowing it in pill form. (And apparently an old Chinese treatment, “yellow tea”, was essentially the same thing.)

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The problem with the pills is that the stuff inside is freeze-dried, so you won’t get a complete biome sample from that. Alternately, you can get a tube through your nose and down, down, down…but that can cause irritation and damage. Enema is your best bet :stuck_out_tongue:

You know I think I might be happy with a partial one to avoid the enema?

Oh and if I just had a pound for every time I’d been told that in relation to poop…


Actually you’re wrong, I have a mate who works for the NHS (British National Health Service) as due to illness last year he was temporarily moved away from his normal job to cover somebody who was involved in the production of ‘sh*t smoothies’ where they would take healthy poo and process it into a drink for people lacking certain bacteria. it goes down exactly the same route as Soylent does!


As far as I know, the final product in that case doesn’t contain fecal matter, just the cultures and a nutritive slurry to feed them. I could be wrong about that, though; that’s just the impression I get from looking at the processing it goes through.

I wonder what the bacterial population looks like after passing through stomach acid? I guess the best method depends on which region of the intestine is having issues.


I vaguely recall reading something about frozen poop pills or something like that, if anyone is brave enough to google that.

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