Lethargy and lots of poop


I and a couple friends have tried Soylent for about a week and a half. My friends seem to be doing fine drinking one day’s “dose” (maltodextrin 409g, etc.) over about three days. I’ve only done a total of four days. I’ve been feeling lethargic, and producing very large, soft, wet feces (fairly disgusting).

Could my intestines be failing to absorb the nutrition in the Soylent?

If so, what could I do about it?

Further details:

First day on Soylent: After downing my first three cups, I felt “wired” for a couple hours: so much energy, I couldn’t focus. Then I “crashed” and napped for a couple hours. The rest of the day went OK: I had energy and was calm. After 24 hours, I had finished the batch and was very hungry. Had the first of the huge poops.

Went back to normal food for a few days. Back to normal poop.

Second day: No energy rush or crash. Lethargic. The taste of Soylent now seemed disgusting (possibly because I diluted it with more water). Felt slightly queasy; hard to describe. Huge poop again. Didn’t feel hungry until after 24 hours, and then felt extremely hungry.

Third day: I mixed up a batch with a creamier consistency, and that did not seem so disgusting. Drank about 2/3 of the batch. No energy rush or crash. Mildly lethargic, and not hungry. Slight queasy sensation. Another huge poop.

Fourth day: Drank two cups in the morning, and nothing else. Queasy sensation continued. Felt some burning sensation from my esophagus. Drinking a bunch of water helped that. Very lethargic. Not hungry. Produced another huge poop.

Fifth day (this morning): I haven’t had any Soylent yet. I still feel that icky feeling in my throat. I don’t feel hungry.

We are all male college students.


Post your recipe and we might know more. :slight_smile:

What I can already tell you is that you need to “eat” regularly.
You will never get used to Soylent if you have it for one day, then a few days break, then having some, then not eating anything for 24 hours, then…


Here’s the recipe:

409 g maltodextrin
102 g whey protein
65 g olive oil
28.4 g potassium gluconate
0.15 g ferrous gluconate
7.4 g magnesium gluconate
2.5 g calcium carbonate
1.5 g choline bitartrate
6 g table salt
4 g fruit pectin


omega-3 fish oil & vitamin D (180 mg EPA, 120 mg DHA, 1 g fish oil)
Nutrilite daily multivitamin
10 mg vanadyl sulfate
5 mg lithium aspartate


If I’m not blind, there is no fiber in there - it’s only natural that you would poop water!
What you are doing at the moment is comparable to drinking 4 litres of black coffee a day without eating anything.

It also looks like you could be missing a lot of phosphor, but not sure if that would have any effect on digestion.


Isn’t pectin fiber?

Also, isn’t this recipe pretty typical Soylent? I thought most people who’ve tried Soylent so far found that they hardly pooped at all, because pretty much all of it gets absorbed. I seem to be producing a lot more poop. So, I’m wondering if there is some individual difference or other causal factor at work here.


Did you drink protein shakes before? Maybe you have problems with the whey.


I’ve never had a protein shake in my life. Can you tell more about what you have in mind regarding whey?


Pectin is only soluble fiber, while bulking insoluble fiber may help some of the poop issue.

I think what @Nicklbak is getting at is a lactose intolerance? Perhaps whey protein isolate would be better?


Yeah, this is basically just sugar, water and multivitamins - hence the blood sugar spike and crash.

If your source of Whey is Whey Powder, then this will include protein, but also a load of Lactose, as @cameronmalek said. Lots of people have trouble digesting Lactose - and even if you don’t, it’s just more sugar.

You need more fibre to slow things down:

Plus probably a bit less sugar - and as @cameronmalek said, look into Whey Protein Isolate, if you’re not already.


We are indeed using whey protein isolate. (I’m not lactose-intolerant, anyway.)

BTW, I actually don’t care about the poop. I’m concerned about the lethargy. I’m hoping to “thrive”, just like @rob. The combination of lethargy and lots of poop makes me wonder if I’m not absorbing much of the Soylent, especially given that other Soylent users are pooping almost not at all.

Does anyone have or know of any experience with different levels of absorption?


Say, could it be gut flora feasting on my Soylent?


Your digestive system is one single connected system. Think of it like a vertical pipe - the speed that stuff falls out the bottom controls the speed of everything further up, to a large degree.

If you don’t have enough fibre/bulk and things move too fast, you will get diarrhoea and won’t be able to absorb things - they’ll be moving through too quickly.

You gut flora will also be playing a part in this, as they help you to digest food in general - and carbohydrates in particular. If things are moving through too fast, they won’t have time to digest anything either, so again, less absorption for you.

Also, if things are moving through to quickly, undigested shorter chain polysaccharides will be making it further down the gut than normal - which will provide a bonanza for the flora in your colon, which normally only get much longer-chain, harder to break down stuff. This will probably encourage an overgrowth of these bacteria, which then irritates the colon and produces a deliberate diarrhoea response to flush them out.

Once this happens, your colon temporarily stops doing most of it’s job - absorbing water, some vitamins and electrolytes, forming solid stools and absorbing carbohydrates from the breakdown of fibre by the colonic flora.

This would result in watery poop and lethargy.

Adding soluble and insoluble fibre to your Soylent should fix this, slow things down, increase absorption and digestion, get your colon working properly and restore your stools. As you will be digesting and absorbing more, especially in the colon, it should also reduce stool volume considerably - because they won’t contain as much undigested matter, water or gas and will have had time to be properly formed.


I was lethargic the first few days too, I suspect it may simply the drastic change in diet. I used to eat WAY more carbs.

Also consider trying a couple fiber snack bars instead of trying to blend something into the shake, that made a big difference for me and regularity (I use Fiber 1 choc & PB).

Another suggestion it starting with only replacing one or two meals instead of the total daily requirement.


Could also be the magnesium gluconate. I have learned that I am sensitive to most forms of magnesium, and since I have spent the extra to get magnesium glycinate (a chelated form of magnesium that is very bio-available), I haven’t had problems like this.


You will find that almost everyone is sensitive to magnesium:
It’s very easy to overdose on (RDA and UL are pretty much the same), and the main symptom of minor overdoses is indeed diarrhea.

This could be the OPs problem considering that they have 400mg of magnesium in their magnesium gluconate and another 100mg in their multivitamin, bringing them slightly over the UL already.

Considering it has been 3 days since the last post though, I’m hoping their issue is fixed with the fiber (an update would be great, @Spidlunt!).
Could of course be that they stopped Soylent. Or died. Hopefully not.


Thanks to all for all the information and suggestions. I think increasing the fiber and decreasing the magnesium are both good ideas.

Before Soylent, I experimented with magnesium to help with concentration, and found that some forms of it would “loosen” stools a bit without having much beneficial effect, but magnesium L-threonate noticeably improved my concentration without any noticeable side-effects. (Magnesium L-threonate is also pretty expensive, so we went with magnesium gluconate.)

It’s near the end of the semester, and I can’t afford to feel sick or lethargic, so I’ve been holding off on Soylent for the last few days. I like what I read in @rob’s three-month post. Before Soylent, I had some success with oatmeal as a main source of energy, and it sounds like a fine way to get both magnesium and fiber. As soon as we procure some oat powder and adjust the recipe, I look forward to another test.

P.S. To clarify some possible misunderstandings: Soylent did not give me diarrhea, and our current Soylent recipe does include fat (65 g olive oil + 1 g omega-3 fish oil in a pill).


That would be a rather ironic danger in designing food with strangers on the internet. :stuck_out_tongue:

By the way, has anyone tried that awesome liquid mercury additive? It makes little silver sparkles in the soylent when you shake it.

Disclaimer: The above was not intended to be a suggestion to ingest mercury. It was intended to be funny.


Don’t eat mercury. it’s bad for you. Like… nom, nom, bleargh, ermargherdidied.


I hesitate to post this as it’s going to sound like I’m tiresomely tooting my own horn, but I will risk it anyway as it’s very much to the point. For a month now I’ve been eating about 80% soylent and the entire time I’ve crapped ball bearings. Sometimes I think my stool is a bit too solid, as it’s a whole lot firmer than my output on regular food, but I’m adjusting to that and it has never amounted to serious constipation – I’m plenty regular enough.

The difference is, though, that it’s my RealFoods Analogue Soylent that I’m consuming, which is made solely with food ingredients without recourse to potassium gluconate, MSM, and other elemental ingredients. Also relevant is the fact that I go to the bother of whey-soaking and subsequently cooking the starches and phytate-containing ingredients; this seems to eliminate completely the risk of any digestive upset. I find this stuff extremely digestible and trouble-free.

TL;DR is this: if you’re having undesired metabolic and faecal consequences with elemental soylent, you might want to give the real-foods approach a try.

EDIT: I should probably point out that my recipe with its cooked whole-grain flours and egg powder results not in a drink, but a custard or pudding consistency. I make it up and freeze it down in individual servings, which I find logistically quite convenient. I can then take it out of the freezer as I need it, let it soften just a bit and eat it as ice cream, or thaw it almost completely and enjoy it as chilled pudding. I often combine it with Jello or Shirriff’s cooked or instant cornstarch puddings for a flavour boost. For me, the pudding texture is wholly positive; I would feel unsatisfied with a meal-drink. (Some people seem to have a big aversion to pudding, or at least express disgust at soylent which is thick or which has a perceptible texture; I have no suggestions for them unfortunately.)