Hide table of contents


Help to find super donors for Fecal Microbiota Transplants (FMT)! By donating stool for FMT, exceptionally healthy people can earn $180,000/yr with little effort. Simultaneously they can help chronically ill people improve their health with a novel treatment. Apply here


More detailed summary

Fecal Microbiota Transplants (FMTs) is a procedure that transfers the stool of healthy people to the guts of sick people. The mechanism is to replace a dysbiotic gut microbiome with an eubiotic, disease-resistant gut microbiome. 

So far, FMT has only been proven to be very effective in curing patients of C. difficile infections. However, since the gut microbiome impacts and regulates virtually every aspect of human health, function, and development, FMT is a promising treatment for a very wide range of chronic and acute health conditions[1][2]

FMTs can easily & safely be done at home, both for the donor and the recipient - no doctor needed.

A super-donor is a person who yields outstanding positive effects as a stool donor. Only exceptionally healthy & fit people are super-donors. They are very rare and a few people within the FMT movement have been searching for them for years. Most donors, even reasonable healthy ones, only yield modest benefits.

Human Microbes, an organization specialized in finding super-donors and connecting them with recipients, is paying super-donors $500 per stool. This adds up to $180,000/yr if donating a daily stool!

Purpose of this post

  • Spread the news that this opportunity for super donors exists: With little effort, they can help lots of ill people (“make them more effective”) while earning $500/stool. You should check whether you are a super donor. If you know someone who might be, please share this post with them.
  • Give a rough introduction to FMTs & Human Microbes, with the aim to start a rational discussion about FMT’s benefits. FMTs look very promising, but there is by no means a clear scientific consensus. I’d love for more EAs to look into this, to get more certainty about its efficacy!
  • If your health is suboptimal, maybe you could consider using FMTs. Not just for obviously gut health-related issues, but much more broadly than you might think. Potentially even e.g. unspecified subclinical low energy, low mood, or mental sluggishness.
  • At the end, this post provides you with a long list of useful further links on FMTs, the microbiome and its connection to a vast amount of (mental-) health conditions. This is to help you do your own research, both as a potential super donor or as someone who might benefit from FMTs.
  • Finally, this post is also a shameless attempt to find FMT donors for me to treat my severely limiting gut issues. Please contact me at anton.rodenhauser[at]hotmail.com 


Who might be a super donor?

  • Donors must be in exceptional physical and mental health. Ideally, top young athletes. Though there are non-athletes who qualify as well.
  • Ideally, donors would be under 30 years old. Donors can be under 18 provided they have signed consent from their parents. Many children need FMT and are ideally matched with young donors.
  • Donors should have minimal antibiotic use.
  • Donors should have a "Type 3" Bristol Stool Type.

Check out the links at the end of this post for more information and sources. 

As you can imagine, super donors are very rare and thus very high in demand. In fact, Human Microbes has screened over 25,000 donor applicants so far, including hundreds of college and professional athletes, and still hasn’t found that one “perfect” super donor that fully satisfies all their donor criteria! So please reach out to Human Microbes about potential super donor candidates!!


How much good can you do by finding a super donor?

Know an EA whose gut-borne suboptimal health is holding them back from doing the most good they can do? Find them a super donor, or be a super donor for them!

In recent decades, chronic disease has been dramatically rising all over the world. Depending on what standard for “healthy” you choose, the vast majority of people are now significantly unhealthy – both physically and mentally – and the problem continues to worsen.

It is postulated that the gut microbiome plays a major role in this phenomenon – through widespread overuse of antibiotics, c-sections, lack of breastfeeding, and suboptimal diets. And the damage we’re doing accumulates over generations.

Our host-native gut microbiomes have been evolving alongside us for millions of years. If we lose them, we may never get them back. 

Since the gut microbiome has been shown to impact and regulate virtually every aspect of human health, development, and function, a super-donor may be able to cure numerous acute and chronic illnesses - including many with no obvious gut connection at all. 

Beyond that, FMTs from super donors are promising to make people more than “merely not sick”. They can plausibly/probably make many people more energetic and improve their mental health, sleep, and cognitive functioning. There might even be some longevity benefits to doing FMTs from young donors! You could arguably think of FMTs as a form of “biohacking” for optimal performance/health. Check out the “Links to do your own research” section at the end! 

I can picture a future where we identify one super donor among EAs, and then provide FMTs for all EAs who suffer from low mood, anxiety, low energy, some chronic health condition, etc. Imagine the impact of that super donor EA! 


About Human Microbes & Michael Harrop

Human Microbes was started up in 2020 by Michael Harrop in response to the lack of high-quality donors available at other sources – worldwide clinics, hospitals, stool banks, clinical trials, etc. Almost all of the latter ones focus mainly on acute safety, aka “the donor must not have any obvious diseases or illness so he can’t infect or otherwise harm you”. Instead, Human Microbes emphasizes “you don’t want a merely not sick donor - you want a maximally healthy, extraordinarily well-functioning donor - after all, that’s what YOU want to become yourself.”


Virtually all studies use “merely not sick” donors, resulting in poor clinical trial results and putting patients at risk. According to Michael Harrop, this is why FMTs have not yet been recognized by the scientific community as the miracle cure that they might well be. See “Links to do your own research” section.


Harrop still runs Human Microbes alone. From my heuristics and in my experience (ordering stools, having several calls with him, getting help for this article), he is trustworthy and focuses on the science part of things instead of the business part. He writes (and I’m inclined to believe him) that “While many other operations have a primary financial motivation, our motivation is fixing people and fixing society. We aim to find the fewer than 0.1% of people who qualify, and connect them with doctors, researchers, hospitals, clinical trials, and individuals.” I’m a bit less certain about his epistemic standards & humility. Reading his HumanMicrobiome.info (Maximilian Kohler is his alias), I get the feeling that he is extraordinarily knowledgeable on the topic and really cares for the science, but he may be a bit too excited about FMTs at times. There is an AMA with him in the comments!

Why aren’t scientists more excited about FMTs?

To be clear, many scientists are very excited about FMTs. It’s an active area of research. Still, one has to ask: Why are results in FMT studies often mixed? Why do many reports state FMTs don’t work? Why so much poor anecdotal evidence?

Answer (according to Michael Harrop): Virtually all FMT studies have one of the following major flaws:

  1. Poor donor quality. Donors should be under 30, have very limited lifetime antibiotic exposure (ideally none), athletic & low body fat, and good mental health. Firm stool consistency seems important too. Typical donor criteria you see are severely deficient. Stuff like "no antibiotics in the past 3 months, 18-50 yrs old, no pathogens in stool & blood test".
  2. Insufficient treatment length. Many studies only do a single infusion, but for many people/conditions you might need to do it daily for 2+ months (Eg: ASU autism study).
  3. Too much oxygen exposure. Blending is quite common and this oxygenates the stool sample, killing anaerobes, and thus very likely reducing efficacy.
  4. Colon-only procedures. The small intestine is very important, so completely ignoring it is a likely flaw for some conditions.

The above is mostly copied from here (link provides lots of evidence for above claims). 

Judging by donor criteria, some of the best FMT studies are coming from a Danish hospital. They made great efforts to find a super-donor. Out of 700 applicants, they only accepted the top 4 “healthiest” ones. They did get better results for C. difficile, i.e. a 100% cure rate, vs the usual 80-90%,  yet failed for IBS and UC. Here is a nice article about it. However, Human Microbes was in contact with the top donor mentioned in the article, and not even their donors passed Human Microbes’ criteria. Thus it is not surprising (according to Human Microbes) that their studies for IBS and UC failed. 

The hypothesis (yet to be tested, but strongly implied) is that FMTs with stools from exceptionally healthy donors, according to Human Microbes’ even stricter criteria, combined with using only “correct” procedures (see above), would show much better results than the above or any other existing study out there.


Effective Entrepreneurship opportunity

I believe that Human Microbes is a great effective entrepreneurship opportunity. Michael Harrop would be more than glad to have some savvy EA business people take over his Human Microbes, which is more like an “amateur project” at this point. He has written to me: “I have no knowledge, interest, or expertise in running a business. My own poor health is typically very limiting. I didn't start out with the intention to create a business. But I think it will need to go in that direction. And I would love it if I could find someone able to do a good job at it. My expertise is knowledge & understanding of human health, development, and function, and the gut microbiome & FMT, and thus screening & selecting stool donors.

He also told me he’d be passionate about people helping him do proper scientific studies with very high-quality super donors - something that has apparently not been done so far. At the very minimum, he’d like to do some citizen science with the help of some proper data scientists/study design experts. 

I’ll write a separate blog post about the “effective entrepreneurship” side of FMTs. 


I am an EA who has benefited from FMTs with stools ordered from Human Microbes. Now I’m writing this blog post to help the cause of FMTs. I strongly want to encourage anyone with super donor potential or who knows someone like that to contact Human Microbes. 

Also, my own health is still quite bad, so I would be extremely grateful for any potential super donors to reach out to me as well. 


Aella did FMT with (I think) Nate Soares as her donor. Nate certainly looks like a super donor to me - someone please tell him about this post!

Michael Harrop’s vision is to identify a 10/10 super donor and, via FMT, use their stool to help upgrade the stool of 'very good' donors to a 10/10 as well. This should help to scale and trickle down the superior health benefits to other people. He says it is plausible but not certain that this will work.


Questions? AMA with Michael Harrop in the comments! 

I’ve arranged for Human Microbes’ Michael Harrop to hang around in the comments. Feel free to ask him any questions! Even if your question feels dumb, or if you haven’t read this full post. Michael Harrop is extraordinarily knowledgeable about this topic! I’d be especially curious about your reasons for being skeptical, for “not buying into this”, or for not trusting Human Microbes/Michael Harrop. If your health is suboptimal, what stops you from trying FMTs as a treatment?

Links to do your own research


PubMed: “Fecal Microbiota Transplantation: Current Applications, Effectiveness, and Future Perspectives”:



PubMed: “Fecal microbiota transplantation broadening its application beyond intestinal disorders”:



Review article: ”The Super-Donor Phenomenon in Fecal Microbiota Transplantation”:



Scientific article on the “microbiome crisis & endemic suboptimal health”:



“Preserving microbial diversity: “the loss of our ancestral microbial heritage, to which we were exposed through millions of years of evolution, may be the driving force behind the dramatic increase of chronic disease”



Diet-induced extinction in the gut microbiota compounds over generations


On the same topic:



Article in “Frontiers in Microbiology”:

"It is now clear that the gut microbiota contributes significantly to the traits of humans as much as our genes, especially in the case of atherosclerosis, hypertension, obesity, diabetes, metabolic syndrome, inflammatory bowel disease (IBD), gastrointestinal tract malignancies, hepatic encephalopathy, allergies, behavior, intelligence, autism, neurological diseases, and psychological diseases. It has also been found that alteration of the composition of the gut microbiota in its host affects the behavior, intelligence, mood, autism, psychology, and migraines of its host through the gut-brain axis." (2018): https://www.frontiersin.org/articles/10.3389/fmicb.2018.01510/full

Keep in mind that a common theme is the lack of high quality donors being used in most studies, due to the difficulty of finding such people. So we should see dramatically better results once we do find people who meet the ideal criteria. 


Diet-induced extinction in the gut microbiota compounds over generations:



Nice informational website:


by Michael Harrop

Michael Harrop’s in-depth FMT explainer (Maximilian Kohler is his alias): procedure, benefits, science/epistemic status, donor screening, etc.:


Michael Harrop: scientific review on numerous health conditions that have a connection with the microbiome and can thus potentially/probably be cured with FMTs. Highly recommended!



How well do FMTs work? What evidence do we have?


One issue is that since C. Diff has proven relatively easy to treat with only 1-2 FMTs, that has been the most common approach for other conditions as well. But for harder-to-treat conditions (most of them) we’ll likely need many more FMTs, as well as higher quality donors. 

Michael Harrop explains “Where are Human Microbes super donor criteria coming from”:


Harrop also writes a lot about gut health and other FMT adjacent topics on his  http://HumanMicrobiome.info.  

FMTs for anti-aging, mood, sleep, brain function, and other “hot” topics 

FMTs, Microbiome & (Anti-) Aging: Forget young blood, you want young poop!


Microbiome and depression & anxiety: Is a suboptimal microbiome making you unhappy and could FMTs change that?


Microbiome & sleep: 


Microbiome & brain function:


about Human Microbes 

Human Microbes’ website:


Here is the $500/stool offer & procedure:


FMT super donor criteria & screening questionnaire:



  1. ^


  2. ^






More posts like this

Sorted by Click to highlight new comments since:

Great post!

I think I would separate out two parts of this post

  • FMT and being an FMT donor as an effective way to do good
  • Being an FMT donor as a means of earning money, hopefully to give

On the first, I would be a lot more hesitant about some of the claims that are being made. The evidence for FMT is young, and relatively weak. I think it is far from being a potential treatment of a broad range of chronic diseases; FMT is currently approved for recurrent C. difficile infection in the UK. Things we do not know:

  • Is it helpful for other chronic diseases? If so, how much and is it cost-effective?
  • Can it be safely administered at home? You make the claim that donation and use of FMT can happen outside of the hospital setting; this is currently not recommended.
  •  Do we need super donors? There is a growing literature around the effectivneess of autologous FMT (use of your own stool for transplantation) may be as effective as a donation from someone else (one paper I am aware of, but I am sure there are many more). I would be hesitant in putting too much stock in one apprpoach early on in the R&D of this area.

On the second, I don't have strong opinions. I think it is worth more explicitly flagging that a super donor is quite a rare statistical occurrence, and that the activation energy and cost to be accepted and donate stool for the first time might not make net positive from a cost-effectiveness perspective ( I have not modelled this, but I wouldnt be surprised if this was the case

Why am I not discouraged by poor outcomes in FMT studies.

FMTs look very promising, but there is by no means a clear scientific consensus on their efficacy. It’s an active area of research with many studies currently under way.

And while many scientists are very excited about FMTs, many studies actually yield very mixed results - with poor or no results being common. Anecdotal evidence on FMTs is also often not very convincing - with many recipients reporting no benefits. 

However, I'm personally not discouraged by this, and indeed still excited about FMTs with good donors. The reason is that in my impression the vast majority of FMT studies and FMT self-experiments are flawed. Here's why I believe this:

1. Poor donor quality. 

Typical donor criteria you see in most FMT studies are severely deficient. The focus seems to be on choosing merely not sick donors, when it really should be about choosing exceptionally healthy donors with fantastic microbiomes. Most studies donor criteria’ are along the lines of "no antibiotics in the past 3 months, 18-50 yrs old, no viruses, infections, parasites, etc. in stool & blood test". In short, if you are an overweight, depressed smoker who regularly eats fast food, you often still qualify as a donor in these studies. And even those studies who do actually try to find good donors that are actually healthy and fit, often don't go nearly far enough - not least just because it is just extremely hard to find exceptionally good donors.

Find me a well-done study that uses donor criteria as described here and takes into account the points below - and if that study still shows only underwhelming results, then I’ll change my mind on this.

2. Oxygen exposure.

Your colon is an anaerobic environment, i.e. very low in oxygen. Thus, most bacteria and even more of the bacteriophages (which might be especially important for FMT efficacy) in stool are anaerobes. However, the vast majority of FMT studies does various processing like filtering, blending, etc. - all of which heavily oxygenates the stool sample, killing anaerobes, and thus very likely reducing efficacy. No wonder these studies show underwhelming results! What you want to do is to immediately vacuum seal the donated stools and suck the air out, and then do all the processing in an oxygen-free environment.

3. No fresh stool, but frozen

Freezing likely kills many of the bacteria and bacteriophages in the stool - very likely greatly reducing its efficacy. Ideally you'd use fresh stool that has been kArticlesept in a de-oxygenated vacuum bag. This is hard to do on a bigger commercial scale, but totally possible if you have your own donor living in the same city like you for DIY FMTs. 

4. Inadequate treatment protocols 

For example:

a) Insufficient treatment length. Many studies only do a single infusion, but for many people/conditions you might need to do it daily for 2+ months (Eg: ASU autism study).

b) Colon-only procedures. The small intestine is very important, so completely ignoring it is a likely flaw for some conditions. When doing FMTs, I'd always combine both the rectal and oral route for FMTs.

c) FMTs done in isolation, instead of synergistically with other treatments. It might well be that for some diseases, even well done FMTs from great donors might not be sufficient on their own, but when combined synergistically with many other positive microbiome interventions, they turn out to be the key ingredient to push the needle over the edge. Yet most studies don't test for this.


Is it helpful for other chronic diseases? If so, how much and is it cost-effective?

I agree that there's lots of unanswered questions, and plenty of theories to test. But we do have lots of data suggesting that FMT would be very helpful for other chronic diseases (http://HumanMicrobiome.info/Intro, http://HumanMicrobiome.info/FMT, etc.). I’m trying to get us to the next stage of demonstrating that it can be highly effective in humans for numerous conditions. 

Regarding costs, I think cost-effectiveness is one area where FMT should shine. Stool is free, and currently has no value. The value derives from what the few extremely healthy people are willing to sell it for. The costs around FMT are mostly associated with finding donors, donor screening, storage, and shipping. I believe there have been a few papers looking at cost-effectiveness of FMT for C. diff, and finding it to be a good choice. https://www.ajmc.com/view/fmt-is-cost-effective-for-any-recurrent-clostridioides-difficile-infections-study-says 

I believe that costs can be lowered even further by switching from a stool bank model to a “direct from donor” model. Yes, there are some cons, but I believe they are outweighed by the pros. 

We started off selling a whole stool (10+ doses) for as little as $150. The only limitation was that we were unable to find the tiny percentage of “ideal donors”, for that price, and thus had to raise prices. We’re currently selling for $100 per dose, and doing means testing for low income people. I think this is plenty affordable, and most other sources of FMT are selling for 2-10x the price. Ultimately, it’s up to recipients/patients to determine if the costs are worth it. But so far, there are certainly many people willing to pay thousands of dollars (much more than we’re charging) merely for the potential to help their conditions. If FMT is demonstrated to be highly effective for many conditions, I have no doubt that people would be willing to pay tens of thousands for a high quality donor. 

Can it be safely administered at home? You make the claim that donation and use of FMT can happen outside of the hospital setting; this is currently not recommended.

Naturally the medical community would not recommend people to perform a medical procedure on their own without supervision. There is certainly some merit to that, and we do recommend that patients get medical oversight from their doctor. 

However, the actual procedure is extremely trivial (swallowing capsules, or performing an enema), and there is no need to have a doctor perform it. There are even downsides (delays, costs, colonoscopy risks, limited dosing, etc.) to having it performed as a medical procedure. 

The primary difficulties with FMT are finding & screening a donor. It would be nice if doctors were able and willing to order the testing, but there are some restrictions with that, and most/all of the testing can typically be ordered online. 

There is a growing literature around the effectivneess of autologous FMT (use of your own stool for transplantation) may be as effective as a donation from someone else (one paper I am aware of, but I am sure there are many more).

I would strongly disagree that autologous FMT has been shown to be similarly effective as FMT from a high quality donor. We have reports of 50% improvement for autism, and 90% of IBS patients improving. 

I do not think aFMT is logically or scientifically supported by the current gut microbiome and FMT science (including much of what was referenced in the OP). I have an FAQ page here that provides some commentary and citations on aFMT: http://HumanMicrobiome.info/FAQ

This quote from the aFMT paper you linked actually supports my donor-quality hypothesis:

the microbiome of a healthy individual can deviate from an ``anti-inflammatory” (healthy) state to that of ``inflammatory” state of dysbiosis

In so far as what they’re considering “healthy” donors are actually not healthy. And they actually have dysbiotic, unstable gut microbiomes. 

One of their other main arguments seems to be that an unhealthy gut microbiome (of the patient being treated) can sometimes be less dysbiotic. Yes, that’s certainly true. But I don’t think that supports using aFMT over FMT. An ideal donor should be much safer and more effective than using a “merely not sick”, or even a sick patient. 

Another one of their main arguments is the lack of difference some studies show between aFMT and FMT. Again, my opinion is that they are merely demonstrating that their “healthy” donors are actually non-ideal donors. 

I would say that FMTs are very safe to do at home. After all, you are just swallowing some pills or do an enema. The tricky part is donor screening for anything infectious. But it is easy to find out what to screen for and order the tests online or get a doctor to do them for you. 


But yeah, doing these tests for the donor is absolutely necessary, and it can be  dangerous if the donor isn't thoroughly screened! 

>Is it helpful for other chronic diseases? If so, how much and is it cost-effective?

I totally agree that the science isn't settled yet at all! But please see the “Why aren’t scientists more excited…” section. 

Also keep in mind that for many chronic diseases alternative effective treatments simply don’t exist yet, e.g. chronic fatigue syndrome, IBS, etc. Sure, the evidence on FMTs may not be conclusive. But it is at least suggestive. And that’s much better than nothing for many chronically ill. You don't need "definite proof" to make it worth a try, given that it is fairly easy, safe, and cheap (if you know the donor and he just gives his stool to you) to do FMTs yourself!


High Impact Athletes might have more potential super donors than the general population:


That's a great point! In fact, my next step was contacting them. Anyone knows them and might be able to introduce me?

Does anyone have any direct contact for the program? I filled out the google doc for my son as I think he has the potential to be a great donor, but I haven't heard anything.

fightaging.org on "Towards the Use of Fecal Microbiota Transplantation to Rejuvenate the Gut Microbiome":   https://www.fightaging.org/archives/2022/07/towards-the-use-of-fecal-microbiota-transplantation-to-rejuvenate-the-gut-microbiome/

I think you are missing out on the more important healthy population. There is a plethora of older “very healthy” individuals that didn’t get that way and stay that way by accident.

Our microbiomes age with us and gets worse over time. You can actually predict a person's age just by looking at their microbiome.

That's why you want as young as possible donors. And that's why FMT might even be a longevity intervention. You can rejuvenate old mice with FMTs from young ones! 

rmative. i’ve learned a lot, and realized how thankful i am for my health/lifestyle, and the efforts i do for my family to be healthy .

question would you accept poop from a toddler? i’m still nursing her and she’s 18M+, i had no epidural, ideal birth, no induction, i did delayed cord blood clamping, i barely took birth control pills and i’ve had limited exposure to meds/antibiotics/steroids, i’ve always healthy and clean, alkaline since 10+ years, healthy stool type 3, super slim, little to no body fat, high metabolism, athletic, under 30 y/o, my daughter also has had little to no exposure to meds, my daughter is not vax to anything (yet) [were waiting for a few reasons] although i was vax’d… anyways my son has a very clean and healthy body. i think i do too.. i grew up i a culture where we would cure ourselves with plants and herbs, passed from generations , we had little access to the western meds and zero exposure to emf, and grew up eating my mom’s home grown vegetables and ate home 90% of my life. not sure if any of these “things” helped keep us healthy and thankfully we had no diseases or problems in my family aside from some cousins who lived near a power plant and used too much fluoride and had BPAs all around her so developed some health issues sadly.

i’ll be happy to connect and am curious if me or my daughter or husband would be good candidates or that one “super” example.


Curated and popular this week
Relevant opportunities