Oat Soylent vs. Old Soylent analysis


This is going to be somewhat of a long post, but I think this is a discussion we need to be having, so bear with me and give us your thoughts as well.

So, I’ve noticed that some people have switched their recipes to reflect Rob’s three month post, while some have been sticking with the original. I thought perhaps we could discuss the pros and cons of the new major change in formulation, the addition of Oat Powder/flour, which totally or partially replaces many of the other ingredients and greatly increases the amount of fiber in the drink. Here are some initial thoughts on the pros and cons of switching to oat soylent:


  • Lower glycemic index. This is a real good thing, providing both “fast” energy, and “long” energy, and is easier on the pancreas.

  • Cheaper. Considering the Oat powder itself is inexpensive, yet it replaces many of the other more expensive ingredients, this formula is likely to be substantially cheaper. By using oat powder, one uses less protein, maltodextrin, and olive oil, but can potentially also save on micronutrients such as potassium, magnesium, and iron.

  • Taste. It seems easier to make oat soylent taste good, or maybe it is just because I had gotten kind of “sick of” the taste of old soylent, so the change is nice. Less oil is always good for taste, and the drink is also less sweet (the sweetness really begins to bother you the longer you stay on soylent, in the beginning it helps it be more palatable).

  • Possibly better for gut flora. I would hypothesize that having more fiber, a greater variety of carbohydrates and fiber types may help prevent a long term loss in the biodiversity of the gut. I’m not really an expert on this subject, perhaps someone more knowledgeable could comment on this point, but I do know that different species preferentially metabolize different chemicals and so there is some concern that the lack of variety in soylent may provide a competitive advantage to some species or the other, which could in turn cause a change in the gut flora with an unknown effect. It may be worthwhile to do have someone do a gut flora culture study for people who have been on a soylent-only diet, and it would especially be helpful to be able to compare this for different forms of soylent and the general population, but that would be some serious science/medicine and is probably not going to happen for some time.

  • More fiber, and avoids possible issue with some forms of soluble fiber blocking absorption of maltodextrin. From what I can tell, this was the primary motivation for Rob’s switch. I’ve been trying to find more information about this, but can’t seem to find any. I assume that the fiber Rob was using before was wheat dextrin, as that is the most commonly sold soluble fiber powder (benefiber and its generics use this form), but I can’t find any sources that say that wheat dextrin blocks the absorption of maltodextrin, or to what extent that should be a problem with the levels of fiber we were using. @rob I would welcome any comment or additional information on this issue. I’m trying to find any publications attesting these claims.

  • Includes something “natural”, which may or may not mean anything. I’m not a big fan of this bias people have toward “natural” vs. “artificial” ingredients, as these are loaded terms and are often used for marketing reasons and are not necessarily reflective of any differences that have been established by science. However, soylent being almost entirely “unnatural” could be a source of unforeseen long-term problems, though most of these we are likely to discover as we go and much of people’s paranoia about this seems overblown in comparison with our lack of concern over people eating known unhealthy diets (like the American diet) and apparently being able to live that way for quite a while. If there is some sort of trace essential nutrient that is unknown to science, there is at least some greater chance that we can get some of it by including some actual “food” in our food. Most of the benefit I imagine may come from including something “natural” like oats is encapsulated in my speculative hypothesis that oat soylent may have greater longterm sustainability specifically for cultivating proper gut flora, but the “risk” to gut flora with old soylent may be entirely mitigated by the use of probiotics, which it appears most people are doing.


  • Somewhat of a departure from what I have perceived to be the “philosophy” of soylent, the experiment of creating a diet custom tailored with everything the body needs in the purest possible form and almost nothing else. There are plenty of meal replacement products out there, and people have been making “health shakes” for a while. Many have responded to soylent with the criticism of “Why not just make a smoothy with spinach, berries, etc., etc., etc”. While I’m not necessarily opposed to someone creating an optimized diet out of existing foods and doing so with some amount of scientific rigor, the soylent concept was different from such approaches in that it started with what we know the body needs and aimed to combine those things as efficiently as possible, as opposed to starting with existing foods and combining them to cover everything the body needs. Having total control over everything that goes into the drink seems useful, and this is the main argument that people have put forward for acquiring every nutrient as separately as possible instead of relying on multivitamins and the like. There is no real reason not to put “food” in our “food”, but the experiment began with conjecture that we don’t actually need food, just the chemicals that it contains, and oat powder seems to be closer to “food” than any of the ingredients we have used thus far, though someone could apply a similar criticism to oil, but whatever. I’m not sure how much this point matters, but it is something that occurred to me.

  • Mouthfeel. Oat powder doesn’t really dissolve, so the drink kinda sticks to your mouth and throat as it goes down, this make me cough and feels kinda gross. Maybe other people have ideas on remedying this and creating something closer to the smooth, somewhat frothy, mixture I have gotten used to.

  • Harder to digest. Again, this may not be a significant difference, but it is necessarily true because oat powder has to be “digested”, while most of soylents traditional ingredients need only be “absorbed”. There seems to be quite some concern about the phytic acid thing and the potential for decreased bio-availability. I’m not sure how much of a concern that should be. I know that the oats themselves can release an enzyme to break down the phytic acid, and many have said that cooking or soaking are ways to release this. Part of the problem I’m having in determining the importance of this issue has to do with the fact that a lot of “healthfood people” who write about his kind of thing online seem to be pretty soft on the science. I never know how much stock to put in the claims of the “whole food vegan types”, although I’m sure there are plenty that do good science, a lot of them seem to overstate the case and cite information that seems to originate from within their own community and there is certainly an ideology that guides their selection and interpretation of the data. Nevertheless, they are clearly eating healthier than the average American, but there seems to be a lot of conflicting and dubious nutrition information floating around out there. For those who are concerned about reducing the phytic acid in oat powder, I have an idea that I will make another thread about.

  • Less compatible with multivitamins and potential to get too much of certain nutrients, especially manganese or iron. It become very difficult to find multivitamins that leave out the things that oat powder contains but cover everything else. To make a proper oat soylent, one would probably need to do everything separately. This may cut down on the convenience factor.

  • Potentially reduced shelf-life.

  • Lack of uniformity in the nutritional content of oat flour especially between vendors.

  • Possibly less beneficial to those with gastrointestinal disease, people who benefit from the gut rest and low waste condition of the soylent-only diet.

  • Not as compatible with ketogenic variants of soylent.

What do you guys think? Are you making the switch, or holding back? What has your experience been, and can you offer us any information that would shed light on the questions of fiber intake and bio-availability?


Hey thanks for this. I’m not sure why no one has replied but this is a great post. I am planning on using Oat Powder from myprotein.com but their nutrition information only lists this:

Per 100g:
Energy: 388.0cal
Protein (dry basis): 8.5g
Carbohydrates: 70.7g
of which sugars: 0.8g
Fat: 7.9g
of which saturates: 1.3g
of which mono unsaturates: 3.3g
of which poly unsaturates: 3.3g
Dietary Fibre: 8.8g
Sodium: 30.0mg

Do you think this is accurate? Why wouldn’t they list other nutrients such as manganese? If there is truly not anything else but what’s listed there, then this would essentially solve the issue of Oat Powder + multi vitamins.

As far as the consistency of oat powder vs the original formula, I personally think it’d be a lot more safe to have something in that required digestion.


Check Wikipedia http://en.wikipedia.org/wiki/Oats, oats contain lots of iron and magnesium. You might also want to try looking up a particular product here http://ndb.nal.usda.gov/ndb/search/list.


I have found White Bean Flour to be a good alternative to Oat Powder: http://discourse.soylent.me/t/an-oat-alternative/2776


Myprotein responce to me.
Thank you for getting in touch about the Instant Oats.

The information that we have is:

ENERGY 1639 kJ 388 kcal
Of which SUGARS 0.8 g
FAT 7.9 g
of which SATURATES 1.3 g
of which MONO UNSATURATES 3.3 g
of which POLY UNSATURATES 3.3 g
SODIUM 0.03 g
IRON 0.002 g
ASH 0.8 g

Im asking them about the ashes and am expecting an answer in a few days
it’s important you ask the suppliers of instant oats specific content. because it’s seams not containing any phosphorus


I can assure you oats have both phosphorous and manganese in them. Companies have to pay to provide nutritional information about their product. Just like Soylent they have to have it sent to a lab, and tested for nutrition. Most companies will not be bothered to pay for and provide information that exceeds the minimum required by law.

Therefore the best option we have is the USDA database which even then does not test for and provide every micro nutrient and mineral we would like.

If Soylent wants to benefit the world, themselves, and the DIY comunity, perhaps they could take a small percentage of their profits and put it towards filling the gaps in humans nutritional knowledge about food. They could start a complimentary database to the USDAs and provide information about foods USDA does not have. Or correct errors or provide more complete information than the USDA.


yes but then the question is how much in the instant oats, and do you get all that you need.

It would be really good if the Soylent Team could do that