Soylent, IBS, the low-FODMAP diet, and gut bacteria

I first heard about Soylent near to when the first press coverage started to emerge, and I immediately saw its potential as a way to help with my IBS symptoms. Now that its nutrition facts have come out and shipping appears close, I’ve become extremely interested in investing in a test week for myself.

For the past two years (versus 6-8 years of experiencing IBS) I’ve been managing symptoms with a combination of probiotics, in particular the Kroger 4X variety which is a knock-off of Align, and a somewhat new kind of treatment called the low-FODMAP diet. You can google that and get a variety of pretty similar lists of foods to avoid, which for the most part lines up with what I can and can’t have. It works on the principle that certain carbohydrates tend to be poorly absorbed in the small intestine, causing gas. They also draw water into the bowel which tends to dehydrate me and give unpleasant movements.

However, it’s extremely difficult to eat well on this diet. I don’t follow the list perfectly, because if I wanted to, I would have to eat many of the same foods repeatedly or spend a lot of extra money that I don’t have, as a student. Some days, I feel hungry constantly because I’m still recovering from the previous day’s excess. It becomes a cycle as I try to eat more again the next day and just make myself sick. So, a product like Soylent seems ideal to me, right? Right.

I’m wondering if anyone else has any idea if Soylent is compatible with this sort of diet. From what I can tell, it looks pretty tolerable, but if someone had experience with this or someone with more intimate knowledge of the nature of Soylent’s ingredients could tell me if anything lines up.

Part of my concern comes from this this thread. I’m concerned about the long-term effects that a completely undifferentiated diet does have on gut bacteria. Sure, I could eat soylent the rest of my life, but this idea of " “dependence” bothers me. That thread hasn’t been updated in a while, but I wanted to check back to see if there was any other input to give on this. Have there been any developments on this potential issue? This is a big concern and one of my only concerns with buying it all, since a week test wouldn’t tell me about long-term effects on my body.

Oh! I have a friend with the same problem on the FODMAP diet. She is also optimistic about Soylent for that reason. That diet is whack, but stomach problems are whacker.

As for gut bacteria, I don’t think it’s really cause for concern. Worst case scenario, there’s a really easy (though kind of gross) way to correct bad gut bacteria; FMT.

yup… getting someone elses poop transplanted into your butt :smiley: (to make it sound childish)

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Sure, I’m aware of fecal transplants. But is that really a solution? What I’m reading seems to suggest that loss of gut bacteria is almost certain to occur as only the bacteria that can feed off Soylent will thrive. A fecal transplant isn’t exactly a casual clinic procedure, either. If I return to eating regular food, and lack of gut bacteria is a problem, I could experience my current problem but so much worse and not be in a position to get a fecal transplant.

I’m no expert on the whole Gut Bacteria area but I would have thought that if you at least eat some normal food along with Soylent that should be enough to keep them going. My plan is to have Soylent for 2 meals a day and then a normal meal either at lunch or for dinner, this way any unknown impact of eating just soylent should be at least reduced enough so it doesn’t really matter.


Or you could “eat” soylent as a solid. I bake mine.

I’m curious - has there been any investigation on the effects of a soup-based diet? (Not that I have any specialized knowledge) I’d assume that if you’re getting the macronutrients you need from sources your body doesn’t outright reject, I can’t imagine it causing problems with gut flora. Again, not a doctor here.

Soylent can’t be worse than that, though.
It’s not a “single component” diet, it’s a conglomerate food that provides the same ratios of ingredients on a constant basis (like eating a ceasar salad with chicken every day).

As far as i can see the official soylent and possibly most or all soylent recipes are fully IBS safe.
To pass as a low-FODMAP diet soylent would have to conform to the following rules:

Fructose content should be equal to, or preferably lower than glucose with an excess fructose limit of less than 0.2 g per serving.

galacto-oligosaccharides(galactans) and fructans limit is less than 0.2 g per serving.

Sugar polyol limit is less than 0.3 g per individual polyol or less than 0.5 g per total polyols per serving.

The product should be certified lactose free

The prodcut should be certified gluten free


In addition to this there is the issue of the minerals used in soylent, the chelated versions of minerals are know to cause the least gastro-intestinal distress.

I believe that if soylent follows all these rules, and finds a non-fart form of fiber to use then this would be a perfectly gas-free product. It might even be a good idea to add these rules to the diy application


I started a recipe for Low FODMAP Soylent. Over the next few weeks I will try to search for a complete list of ingredients that are low in FODMAPs. I would love some help in doing the search for these. Please talke a look at what I have started with a suitable carb?:
Maybe you guys can check it as we hack on this together. Onwards!

I think this is a good idea, it really does not matter which ingredients you use as long as you end up within the safe limits outlined in my previous post and choose chelated minerals and vitamin c in the form of calcium ascorbate.

I did some googling and found that we should probably start the recipe like this:

gluten free Whole grain oat powder as the carb source
Hemp seed proteine as a fodmap free complete proteine source (maybe we could even use the whole seed, as its fodmap free)
The alternative to hemp seed would be rice protein and pea protein mix but pea’s are not fodmap free so we can only use a small amount.

The hemp proteine and oat powder might already give us our total fiber amounts, however if they do not we can add phisylum husk.

As far as FAT goes, they do not contain any FODMAPs so we are free to choose.

This gives us our 3 macro’s to further tweak the macros with, asburq would you like to update the recipe?

Here is some more reading material:

EDIT: we could start by using this as a source of vitamin C and some calcium:

EDIT2: a IBS friendly source of magnesium:

EDIT#: IBS friendly zink:

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Thanks for the ideas. I will update the recipe. Do you know if there is a way to allow other users to edit a recipe?

So I have updated the recipe with the macros. Still need to add the amounts.
Can you have quick look. For vitamins I have added these pills but I am not sure if they are IBS friendly. What do you think? If not I can add your suggested zink and mg.

Hi saburq,

I had been working on a recipe of my own because i could not edit yours, it is still a wip, you can find it here:

My feedback on your recipe would be:

  • Coconut milk is not an IBS safe ingredient
  • It turns out the hemp protein has way to much manganese
  • The vitamin pills seem to use IBS unfriendly vitamins and minerals for almost all of them.

I had to revise my recipe several times to deal with all the ibs exceptions while still keeping the vitamins and minerals in the safe ranges.

Okay i finished my recipe, it looks complete and IBS safe to my eyes. No idea how it tastes or feels in the mouth though.

The next step would be to find a way to get more a more realistic ingredients, nobody is going to measure off 0.001 grams of something.

So what would be prefered is finding mixes of vitamins and minerals that only contain the specific versions mentioned in my recipe.

Hey all,

I have a variety of food intolerances and sensitivities including gluten-intolerance, dairy-intolerance, and IBS. Whew.

Unfortunately my sensitivities seem to include (even gluten-free) oats, so I’ve been looking for a soylent solution with a different base. Tomorrow morning I’m going to try my variation on the corn-based People Chow:

Currently, my biggest concern is taste, but we’ll see tomorrow.

My goal is to do a (hopefully) low-fodmap, low ibs triggers, gluten-free variation that is also relatively low-carb. I’ve also been futzing with a coconut flour variation, in case corn becomes a problem.

If you have a minute, I’d welcome a recipe critique, and I’ll let y’all know how it shakes out.

Ok, after a week, I’ve discovered a few things:

1.) Psyllium husk powder is totally disgusting
2.) I bought the un-cooked masa, so I was getting pretty low calories at first. I tried cooking the stuff, but with the psyllium, it got super nasty. I’ve been making due by using extra masa.

I’ve updated the recipe with flax, which I’ll try tomorrow. *fingers crossed.

Ok, two weeks in and I’ve realized that, while it’s been nice to lose the weight, I’ve largely been starving myself. I was wrong about the masa being uncooked. It’s just that 1650 calories, surprise surprise, is not enough for a 6’ 2" man who exercises.

Now that I’m in better shape, I’ve been exercising more, so I’ve bumped up the calories to compensate. Here’s the latest blend:

The other thing that’s been AWESOME is I’ve added a digestion enzyme to my typical day. I cannot stress enough how much this has generally improved my GI tract after only three days.

I’m taking this as well:

But, for God’s sake, don’t grind it into the Soylent! Worst. Taste. Ever. I had to throw an entire batch out.

Next thing I’m trying is to add a probiotic. I’m seriously thinking I might have these intestinal problems licked. :smile:



did this diet help any of you overcome IBS?
How are your respective experiments going?


So far … pretty good. Some ups and downs.

Some main points:

1.) I cannot express enough the difference between the coarsely ground “Tamal” masa harina and the very finely ground regular Masa Harina. I originally accidentally used Tamal, which radically changes the taste and feel of the Soylant. The only downside of the fine masa harina is that it makes the soylent a little chalky.

2.) I finally decided that going too low calorie wasn’t working for me, so I made a new recipe that has more calories:

The extra masa harina made me need to reduce the flax and soy oil and add coconut oil for fat.

3.) I’m a little concerned about the amount of flax/fiber in my recipe. I’ve sometimes gotten constipated after eating nothing but soylent. Though, honestly my GI tract is kind of a disaster and I get constipated just by looking at food. Anyway, I’ve had good results from mixing laxitive powder into my soylent.

4.) But, by far, the greatest positive effect seems to have come from my taking a daily probiotic and a digestive enzyme with every meal. I’ve been using these guys with good result so far:

I did the tests for various sugars from this place:
I can’t absorb fructose, lactose or sorbitol - so in theory I would need to stick to the low FODMAP diet.

I have always had digestive issues - and if I stick to the diet it does fix the problem. The problem is it is almost impossible to stick to the diet - even my doctor said most patients don’t stick to it. So I was quite excited to hear about Soylent!

The last 2 weeks I have been using the official Soylent for about 2/3rd of meals - breakfast and lunch most days. It has definitely improved my digestive issues over not having Soylent - but I am still having normal food as well. The first say 5 days my body was adjusting to it - but as I always have digestive issues this was no worse than a normal day - but after that it started to improve.

I want to try a 100% Soylent diet at least for a time so I could see what happens. It would be interesting to get in touch with Sue Shepherd who came up with the low FODMAP diet. As I live in Melbourne, Australia (her clinic is here) - most of the doctors know all about FODMAPs as most of the research into it is happening here. A lot of people in my family suffer the same issue - so I have given them a bag of Soylent to see what they think as well.

Has anyone else with fructose malabsorption been having official Soylent? I might try a 100% Soylent diet for a week or so soon and see what happens!