My serious issue with Soylent

So I was a Soylent user a few months back, I had used Soylent 2.0 regularly for around 6 months, getting a subscription of 36 bottles per month. I never found anything wrong with Soylent 2.0, I like the taste, I found it filling…but then something serious cropped up. I think in light of the whole Soylent bar issues, my story might receive the attention it deserves. I never brought it up before because I’ve seen what happens to posts on this forum that can harm Soylent’s reputation.

For a few weeks I noticed pain in my pecks. I am a male. Both of them were just really sensitive and sore, and it started getting pretty painful, this went on for 2 weeks before I went to see the doctor. My doctor directed me to get a mammogram ASAP to see what was going on… the possibility of cancer was mentioned. So I make an appointment, get a mammogram, get an immediate diagnosis from physician: It wasn’t cancer, but rather, just a ‘normal’ development of excess breast tissue.

I have no history of this in my family. In trying to find out causes, I spoke with the doctor who analyzed the mammogram, and my general doctor that I see regularly. Both determined that it was most likely the Soylent 2.0 that was causing the problem and directed me to stop consuming it. About 2 weeks after stopping, my right chest cleared up, no sore spots or pain. About a month later, my left side cleared up, no sore spots or pain, and for the most part, things have returned to normal size.

Now I’m not a scientist or dietitian, I don’t know what interacted with what, and at 36 bottle subscription per month, I was averaging a little over a bottle a day in my diet. What I do know is that as soon as I stopped consuming Soylent, I got better. I really hated it because I like Soylent, but this whole thing did end up costing me a LOT of money…doctors aren’t cheap, mammograms aren’t cheap…and honestly, I feel like Soylent is at fault for having a product that can cause issues like this in men. I still have 3 unopened cases of Soylent that I can’t do anything with.

Some of you may scoff, some of you may say “he’s gotta by lying”, some of you may try to come up with your own conclusions that take the blame away from Soylent, and some of you may not care at all…but I ask you to try to not belittle my story with that stuff, because it is my story, and it is 100% true. Long term exposure to Soylent simply caused issues for me.

I’m not saying it will for everyone, but I am a pretty burly hairy guy, no hormone issues…I’ve had blood work done, the kind you need to not eat for a day before taking, nothing wrong with me, all the levels of everything you could measure in my body are perfectly normal, from vitamin levels to whatever else they measure.


Your case isn’t unheard of, it’s just very uncommon. Large studies of male diets show soy intake isn’t correlated with gynecomastia but that’s because the vast majority of men aren’t affected, so the effect size is wiped out because the affected group is such a small percentage of the total population. There’s one case study I know of where soy intake was confirmed as the cause of that man’s gynecomastia and another where it was implicated, it’s plausible you’re affected in the same way and should avoid soy.


Well in a lot of things it’s the dose that makes the poison and few people consume as much soy as you’d get in an exclusively Soylent diet. So that is probably another reason for it being uncommon. Combine an uncommon sensitivity to soy with an uncommon high dose and it’ll be more than either alone, but still rare I’d expect.


It’s been said around the forum before but it bears repeating - there is absolutely no soy in Soylent. There is soy protein isolate. Not soy.

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I think there’s some confusion here. Older versions of Soylent used rice protein and had soy lecithin (as an emulsifier I believe). Soy lecithin does not contain soy proteins, so many/most people with a soy allergy can safely consume soy lecithin (iirc). However, all the current Soylent products use soy protein isolate (as you say), which is most definitely soy protein and unsuitable for anyone with a soy allergy.


Right, soy or not, the product isn’t safe for anyone with a soy allergy

That combined with the duration of the high levels. The effects weren’t instant after all.

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This guy isn’t complaining about allergy symptoms he is complaining about gynecomastia. The fact that Soylent now contains Soy protein isolate is irrelevant to this case. It’s not the protein that would cause this it’s the estrogenic isoflavones in soy that may be causing the problem.


anybody else experience this going 100% 2.0? I know this guy was only consuming 36 bottles, but seriously he has a weird body if this little soy caused all of these problems. Something else has got to be wrong here.

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First let me say I’m sorry to hear about all of your problems supposedly caused by The Lent. I was just wondering what inspired you to write this post about The Lent if you have such a high soy sensitivity compared to other men and a number of other soy-based foods would have likely caused the same issue? could you post your lab results for us? did you ever see an endocrinologist?

For customers interested in the isoflavone levels of the soy in Soylent, one serving of Soylent Drink has approximately 52 mg of isoflavones and one serving of Soylent Powder has 53 mg. Soylent Bar and Coffiest have not yet been tested, but will be shortly.


Which is significantly less than the iso content in actual soy. Isoflavone being blamed at this point is just frivolous.

so apparently the Texas man that consumed 3 quarts of soy milk per day and started to grow man boobs similar to OP was consuming around 360mg of isoflavones. If somebody is drinking 100% soylent 2.0 for a 2000 calorie diet, they are getting about 100mg less than this at 260mg of isoflavones per day. Is anybody else concerned about this? the idea of having liposuction to remove man tits does not sound like a euphoric time.

I agree that the isoflavones are low in Soylent products and we are assuming that it is the soy and not something else that is causing the problem because as we all know soy is evil. But really protein is just a collection of amino acids it’s irrelevant where they come from. Alanine from soy is the same as Alanine from whey.

I will say one thing for Soyelnt it does seem to be great at helping some people find out they have rare conditions that need to be looked at.


I’ve read that article too. I have my doubts as to whether or not it is real but it does seem to have some rather striking parallels to the OP’s problem.

Whether are not it’s true, there are plenty of isolated incidents submitted as research, but they are on individuals and there are maybe 3 cases a year. In science that’s not good enough to implicate a food/chemical itself. No cause and effect is established in any of these cases; they are merely doctors observing their patients and symptoms.

Soy being blamed for gynecomastia is tabloid science. There’s nothing deeper to dig because there’s no actual evidence.


Yea, das true. I just wanna stop worrying about food and drink my Lent and whenever this comes up I get massively worried about no longer having to go to google images to look at big boobies

What would you consider a high daily dose of isoflavones?

When it’s more than my body can handle.

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Why don’t you make it an official diagnosis and consume the rest of your soylent 2.0 and see what happens

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