Soylent vs The Master Cleanse


Years ago I had tried the Master Cleanse (aka The Lemonade Diet) where you eat nothing but a DIY drink made with rich maple syrup, lemons, Cayenne pepper, and pure water. Like Soylent, it was supposed to contain all the nutrients the body required, while it took you off solid foods, overcoming a psychological need to eat. Users would continue for months on this lemonade concoction, however this fasting/ detox program recommends 10-days. Once complete, the Master Cleanse required 3-days to slowly ease out and back into eating complex foods again with juices and soups. The body needed time to recall the digestive process, else your body would go into a state of shock. I think people who’ve been feed through an IV for long periods of time would require the same transition. That being said, how is Soylent any different? What are, if any, the potential dangers of being on an all liquid diet with Soylent?


Sure doesn’t sound complete.


The difference is that Soylent actually contains every nutrient your body needs to survive. For instance, I don’t think maple syrup, lemons, cayenne pepper, or water contain any appreciable amount of protein. You would (eventually) starve to death without consuming adequate protein.

Actual dangers? None that I am aware of, if you don’t have a preexisting medical condition or allergy of some kind. Most people only replace some meals with Soylent; a life without occasional solid food might be somewhat boring. I only average about 1000 calories of Soylent a day, for instance, and I fill the rest with regular food.

Edit: I plugged the three “Master Cleanse” ingredients into the DIY Soylent recipe editor and it was pretty bad (note: it’s actually lemon juice, not whole lemons). Even at 12 glasses a day (~2218 calories), you’d only be ingesting:

  • 3 g/day protein
  • 3 g/day fat
  • 0% of eight different vitamins and minerals

Plus a bunch of other less severe deficiencies. They could rename it the “Starvation Diet!”


There is exactly zero similarity between Soylent and any “cleanse” I’ve ever heard of. Well ok they’re both liquid so I suppose it’s slightly more than zero.


Soylent is different, because Soylent is food, with all the components food is known to need for the human diet. That it’s in liquid form is irrelevant.

Soylent is also different, in that its development is evidence-based. There’s no evidentiary reason for “detox” “cleanses” yet discovered, aside from any possible psychological or spiritual benefit in fasting.

Soylent’s not fasting.


I plugged the three “Master Cleanse” ingredients into the DIY Soylent recipe editor and it was pretty bad (note: it’s actually lemon juice, not whole lemons). Even at 12 glasses a day (~2218 calories), you’d only be ingesting:

3 g/day protein
3 g/day fat
0% of eight different vitamins and minerals
Plus a bunch of other less severe deficiencies. They could rename it the “Starvation Diet!”

In the cleanse the lemon and cayenne are used for cleaning out the pipes, but the suggested main ingredient is natural organic Grade B maple syrup which contains higher quantities of vitamins and nutrients, such as Manganese, Zinc, Calcium, Iron, Potassium, Cooper compared to others. The fact that it is very high in carbs and sugars is probably how many were able to survive for months off the cleanse. Also lemons should be a great source of Vitamin C. You are correct to say its a starvation diet as there are no proteins whatsoever. Perhaps one of the main reasons people sought it out to lose weight.

I remember a few years ago, the media was pushing the idea that using supplement pills were a waste of money because something like 10% was actually absorbed by the body. Could it be possible that 90% of all the good vitamins and nutrients in Soylent is just being flushed out of my system?


There is exactly zero similarity between Soylent and any “cleanse”

I was mainly comparing how both Soylent and the Master Cleanse promises to replace food, and give your body all the nutrition it needs in order to survive.


Soylent’s not fasting.

If you consider Soylent food, then by definition you would not be fasting. But other people fast using Liquid Modified Protein Diets, where there were reported dangers in using them to the point of death or starvation. Often I easily find myself using Soylent, going 12 hours without solid foods. My doctor also might refer to that as fasting.


I’d probably agree with you. Remember the food pyramid where bread, cereal, rice, and pasta was the main foundation? The Master Cleanse was designed in the 40s and renewed in the 70s where their idea of proper nutrition consisted mostly of carbs, outdated compared to today’s idea of proper nutrition. But in those days, that’s how people ate. That’s how all our families ate, and were all still alive.


I don’t think that is possible, no. People have taken blood tests that don’t indicate such irregularities. If it was true that all liquid diets wasted intakes of vitamins, we would have learned that before Soylent arrived.


The master clense diet is dangerous long term due to low vitamins and minerals, low protein and low fat… No fat can cause quite a few health problems, including mental problems. No proteins can cause your body to break down your own muscles and organs… Do this for a while and you will be in a critical condition. Sure you can survive on pure carbs… For some time.

Soylent is nothing like that… People have already thrived on Soylent for years, many being just as or more healthy than before. Soylent isn’t a “diet”, it is just food… It is easy to controle the calories you eat with it, and thus easy to use it for weight loss or gain. But it doesn’t contain dangerously low vitamin/mineral fat or protein levels.


I’m pretty sure in the 40’s and 70’s people ate actual solid foods not sugar water. I find it unbelievable that people survive on this cleanse for months on end. 10 days maybe but not months.

The media says a lot of stupid, misleading, or straight out untrue things. If 90% of the vitamins and minerals where passing through our system I and everyone else who uses Soylent for a large portion of their diet would be dead from deficiencies long ago.

For one Soylent is NOT a cleanse it is food. Master Cleanse has massive deficiencies in protein, fat, calories, vitamins and minerals and can’t sustain you long term.

Soylent is no more dangerous than any other complete diet. The fact that it contains a high amount of water is irrelevant.


Read the “criticisms” section:

WebMD article that is also critical (2nd page is more critical):


A cleanse is just that.

It is not supposed to replace anything. It just cleans you out short term.

Soylent can replace regular food, period.


I think the difference here is “survive” vs. “function optimally”. One can survive for a very, very, very long time and an extremely sub-optimal diet. Just ask a large number of Soylent users who have eaten quite poorly for decades and are still here. Soylent however does much more than just allow a human body to survive.

Also, though I haven’t done any significant amount of research on them, I’ve never heard anything purporting that any “cleanse” is actually good for you long term. As far as I’m aware they are always recommended for a fairly specific and short duration, and usually with the advice of medical supervision. Such “crash diets” are not to be taken lightly. They could kill you if used as directed. I do not believe the same could be said of Soylent.


The only thing “cleanse” diets are good for is “cleansing” your wallet because you just paid someone a whole bunch of money for a book that says “drink lemon juice” or whatever other random stuff from the supermarket.


It’s not so much that I “consider” Soylent to be food, it’s that it is food. It happens to be in liquid form, but so would your steak and potatoes be if you pureed them with water.


I’ve highlighted the differences between The Master Cleanse and Soylent below. Note the red parts.

Also, the manganese is a little high. This may trouble some people.
(But I wouldn’t worry about the Riboflavin; it’s water-soluble.)


I assure you, no doctor will consider 2000 kcals per day a fast.

If that logic is sound, then life should be a lot simpler… you see, all the water you take in every day is either peed out, perspired out, or exhaled out in your breath. This means that all the water you drink or eat is simply flushed through your system; that must mean it’s unnecessary, and serves no purpose, so you can safely stop drinking any water and be fine.

If that logic is sound.

Hmmm, if they’re right, nobody will ever have died of thirst. Can someone check on that? I’m dying to know.


The Master Cleanse was created as a FAST. It was meant to contain everything you need to FAST. Not everything you need in general. It is completely different. The Master Cleanse is a diet, at best, while Soylent is a nutrition plan.

Also, when you fast, MC style, your body doesn’t just digest fat. It digests muscle as well. It needs to get protein somewhere. The cleanse is about the worst weightloss solution there is outside of straight dehydration.

That is not to say there aren’t reasons to use it, but they are spiritual…