Paper on the possible dangers of non-chewing


This paper, which was mentioned in the popular blog, discusses the possible correlation between chewing and cognitive deficiency.

A quick search has shown me that some users report deteoriation in their chewing abilities after using Soylent so I want to advise this community (and perhaps Rob) to look into this. The connection between cognitive defficits and lack of chewing might turn up non-existent but it might be an impoprtant thing to check.

Perhaps a simple advise such as telling people to chew gum while on Soylent might turn up to be a good idea or perhaps something else might be recommended if this is in fact an issue.



Correlation does not imply causation.


Older mammals lose their teeth as a process of aging, which also coincides with cognitive and other forms of physiological decline. This paper is ridiculous.



…but it does waggle its eyebrows suggestively and gesture furtively while mouthing “look over there.”


You clearly didn’t read the paper. The very first cited study at the start of the literature review focuses on molar extraction which is not aging related… The rest isn’t either.


Just chew some sugar-free gum. Xylitol gum is probably the best option for the dental & blood sugar benefits.


jrowe47 is dismissing this too fast. Sure, correlation does not imply causation. So how would you check if it’s correlation and not causation?

Well, you could randomly take animals, extract their molars, and then see what that does to cognitive function compared to the ones you didn’t extract molars from. If it declines, that increases the suggestion of causation a lot! Guess what they did with lab rats. ( The effect of the loss of molar teeth on spatial memory and acetylcholine release from the parietal cortex in aged rats.)

That’s just one of the studies referenced. Chewing gum, as SSSS suggests, is definitely not a bad idea, but may not be enough. “Other studies have suggested that decreased bite strength associated with tooth loss and reduced chewing is also a risk factor for dementia”

Personally I take part of my Soylent in the form of potato chips, but since they don’t offer much resistance, I may go out looking for something stronger. Nuts? Fruit? Not sure yet.


I’ll probably grab some (non-candyish) gum, as a few people have mentioned in the past. Worst-case, it’s generally irrelevant; best-case, it provides some amount of benefit.


That is actually a very interesting paper, thank you for sharing.

There are several ways in which their results could be interpreted. I found it very interesting that the act of chewing appears to increase blood flow in several key central nervous system areas. Part of me believes this could be the Pavlov effect due to the expectation of food. I wonder how well they isolated that from the act of chewing itself?

Good cautionary note, everyone should observe their masticatory health while consuming Soylent regardless based off prior observations of jaw soreness after prolonged avoidance of muggle meals.

Edit: I english well


I’m planning to include some extra food because I’m a believer in fiber for clearing out the system health. But I’m more likely to grab some celery or broccoli which will give my teeth something to do.

Regarding gum chewing, remember that it’s not normal to spend one’s entire day chewing. Most animals (and pre 21st century humans) chew for a relatively brief period about three times a day. It’s part of why I’m a little skeptical about this study. Lots of factors co-correlate with the absence of teeth including the backing off from social life.



Soylent already has quite a bit of fiber as of the last update, so there shouldn’t be much need for extra supplemental sources - it may not necessarily be bad, but it would be a good thing to keep an eye on to avoid overdoing it.


I decided against starting a new thread… But I hope everyone on a mostly-soylent diet takes a look.

I’ve had significant jaw bone loss between October (when I started my DIY) to now. I’m being referred to a specialist because of it. I’m 26-years-old, and other than shitty dental family history, I haven’t had any dental problems.

When I went in for my bi-annual cleaning two months ago, my dentist was not happy. I had some very deep periodontal pockets. No additional x-rays were done, but I was told to start chewing and flossing more. I bought gum and started eating more.

I went back today and had x-rays done. In comparison with the x-rays from just before I started my diet, I have significant bone loss in certain areas. I’ll be going to a periodontist next month to try to stop it.

All of my doctors have monitored my progress since I started my mostly-liquid diet, and this is the only bad news I’ve received from any of them. Of course, my dentist couldn’t say for sure that my lack of chewing caused the increased bone loss, but he was amazed of such a dramatic loss in such a short period of time. I don’t smoke, drink, or take any medication. I workout regularly.

I am super bummed about my jaw situation, but I wasn’t as proactive as some of you have been. I never chewed gum until my dentist pointed out a possible problem 2 months ago. I thought it was silly and couldn’t believe that it could have such a dramatic effect. From November until late February I rarely had solid foods.

Anyway, I’ve invested in some gum, and I’ll be dialing back the S/soylent until things stabilize. Perhaps to as little as once a day…I hope this bad news helps the community.


Wish we could see before and after pictures for reference :confused: also to give better idea of how bad it is


I could upload the x-rays I suppose, but I don’t think anyone other than a dentist could really make a good comparison. Doctor said that it’s not horrible (he has seen much worse), but it’s not good either. Work needs to be done. i just hope it’s just the deep cleaning kind of work, not the bone and tissue grafts kind… Fingers crossed. Made my appointment for tomorrow O:)


The idea that Soylent consumption has a causal link here sounds very much like a post hoc ergo propter hoc fallacy to me. I am 27 and have in the last two years had similar bone loss and deep periodontal pockets. The dentist told me that while my teeth themselves were in great health, if I did not take better care of my gums I would nonetheless end up losing most of them within the next decade. Those pockets have since decreased dramatically firstly from professional deep cleaning below the gum-line (root planing tartar removal) and secondly due to better and more frequent personal dental hygiene, specifically a water flosser, a Sonicare toothbrush, and a chlorhexidine gluconate mouthwash. All of this took place in the absence of a Soylent-esque diet. There is increasing evidence which suggests that the reason some people more than others experience periodontal disease has to do with the particular composition of their oral microbiome, and that periodontal disease is in fact communicable. The take-away is of course to keep one’s endemic oral bacterial population in check by properly cleaning the areas in which they reside. Many of them are obligate anaerobes which to be killed need nothing more than to be exposed to the oxygen in the air via mechanical agitation.


Thanks @SolveDSMV_ARFID. Your message makes me feel warm and fuzzy on the inside. I hope this means that I get to keep my teeth and still drink soylent!

My dentist never liked my diet choice, so I’m not surprised that he’s jumping to this conclusion (although he has hedged the connection pretty clearly).

I’ve just bought a water flosser and I’ll be picking up the chlorhexidine later today. Wish me luck.


I’m sure a few of us here on the forum would be able to analyze the before and after :slight_smile: can’t hurt. It’s very good for reference at least


Good point! I’ll make a new thread later today and throw them up!


I’ve been on 80% DIY for a year now. I went to the dentist a week ago, bone and gumline was perfect.


If soylent is doing anything (or not doing it), it’d be with the combination of not chewing and shitty genetics (and everything @SolveDSMV_ARFID mentioned).


Of course, I’m guessing. This is all a lot of guessing and FYI-ing


To elaborate on the point about communicability in my previous post, sharing food and drink is likely to be a transmission vector for the microbes that cause periodontal disease, so a family history of poor dental health (depending on the type of problems) is not necessarily about poor genetics. Other dental problems like relatively thin tooth enamel probably are genetic however.


Hey, @cheapskate88, just wanted to let you know since you are going in for a deep cleaning tomorrow, if the procedure is anything like mine was your jaw muscles are going to ache pretty bad for a few days from having your mouth braced open-wide for so long. Mine was done in two 1.5 hour sessions, one for each half of the mouth. Ice packs or bags of frozen peas helped a lot in relieving the muscle tension, but after the experience from the first session, for the recovery from the second session I insisted they give me a short prescription for opioid painkillers. Tense jaw muscles were leading to some pretty bad headaches. Other than the residual muscle tension though everything went completely smoothly and within about a week pain was no longer a problem.

In the months afterwards I was amazed at how much my general health improved, especially psychological. We tend to underestimate the insidious effects of chronic oral pain on our mood, and also the stress caused by elevated bacterial load in our bloodstream. (Oral bacteria can end up causing problems throughout the body due to how readily they cross into the capillaries of the oral mucosa, and the then short distance to the heart where they get distributed to the rest of the cardiovascular system. It is enough of a problem that if a medical patient who needs heart surgery has an oral bacterial infection, the surgery will often be postponed until the infection has been resolved.)

Good luck with the procedure!