Prüvit’s KETO//OS stands for “Ketone Operating System.” It’s a drink meant to help rev up your metabolism to burn fat, improve concentration, and energy. The idea is to send your body into a constant state of ketosis, defined by Google’s dictionary as such:
A metabolic state characterized by raised levels of ketone bodies in the body tissues, which is typically pathological in conditions such as diabetes, or may be the consequence of a diet that is very low in carbohydrates. 
WebMD simplifies the definition further:
Ketosis is a normal metabolic process, something your body does to keep working. When it doesn’t have enough carbohydrates from food for your cells to burn for energy, it burns fat instead. As part of this process, it makes ketones. 
Low-carb, paleo, and keto diet programs all aim for this state to one degree or another. You measure your ketone levels with a little paper strip held in your urine stream, rather like checking the pH of your water or soil.
But just because KETO//OS drink mixes claim to put your body into a state of ketosis, doesn’t mean they follow through.
How Does KETO//OS Work?
Using KETO//OS is fairly simple:
Dissolve 1 heaping scoop or [On-The-Go] pack in 12-16oz. of cold water and shake/stir vigorously.
Therapeutic dose = 1 daily serving
Optimal performance = 2 servings AM/PM 
So what exactly does it do?
Or better yet, a question asked right on the Prüvit website:
Why would I take KETO//OS®?
Supplementing with exogenous ketones allows you to experience ketosis – the benefits of elevated blood ketone levels, without having to follow such a restrictive ketogenic diet, or super low carb diet, which is often difficult for some people to adhere to. Optimize your human potential.  (emphasis added)
So something about this formula drops you into ketosis while still being able to enjoy all the carbs you want—seriously, the very next answered question claims you don’t have to change your diet at all. Where have we heard this before?
The Magic Ingredients
The magic ingredients are apparently beta hydroxybutyrate (BHB) salts and MCTs. So let’s see what sort of magic we’re dealing with.
The definition of BHBs on the website is a tad technical, but the gist seems to be that they’re a chemical “salt”—a combination of an acid and a base (neutral)—found in foods like milk and eggs. Sodium, potassium, and the ketone body beta hydroxybutyrate exist in combination until you ingest it; then it breaks up, the sodium and potassium get absorbed just like they do from other foods, and the BHB is left to do its thing by putting ketones directly into your blood system. Ketones act as a diuretic (urine producer), therefore tend to drain sodium, calcium, potassium, and magnesium from your body, so it’s recommended you increase your sodium intake while on this.
MCTs are medium-chain triglycerides—information that was not on the Prüvit website; I had to go back to WebMD for a definition:
Medium chain triglycerides (MCTs) are partially man-made fats. The name refers to the way the carbon atoms are arranged in their chemical structure. MCTs are generally made by processing coconut and palm kernel oils in the laboratory. Usual dietary fats, by comparison, are long-chain triglycerides. People use MCTs as medicine. …
Athletes sometimes use MCTs for nutritional support during training, to increase exercise performance, for decreasing body fat and increasing lean muscle mass, and for weight loss. …
MCTs are a fat source for patients who cannot tolerate other types of fats. Researchers also think that these fats produce chemicals in the body that might help fight Alzheimer’s disease. These fats might also result in weight loss because the body uses them in a different way to other types of fats. 
KETO//OS also contains caffeine—the anhydrous (lab-created) version—which is probably where all that concentration and energy comes from. They do offer a caffeine-free version.
The mix comes in several flavors, in both the regular and caffeine-free versions: Raspberry Lemonade, Swiss Cacao, Maui Punch, Chocolate Swirl, and Orange Dream. You can buy it in a tub and scoop your servings, or buy handy On-The-Go single packets. A thirty-day supply costs a whopping $160 (tub) plus shipping and handling.
There’s no diet plan, no exercise plan, just a powder that apparently can set your body into ketosis even after you’ve had the Big Mac, fries, and chocolate shake (that’s 194 carbohydrate grams in one meal). 
Is KETO//OS Dangerous?
BHBs are a natural substance and MCTs are used as medications. However, if you’re caffeine-sensitive, the anhydrous stuff is just about the worst thing you’re going to ingest. You can choose the caffeine-free version if you want to alleviate that issue.
Reviews have mentioned KETO//OS causing digestive distress, which is never any fun to deal with.
Some of the drink mix flavors do contain taurine. Back to WebMD:
Taurine is an amino sulfonic acid, but it is often referred to as an amino acid, a chemical that is a required building block of protein. Taurine is found in large amounts in the brain, retina, heart, and blood cells called platelets. The best food sources are meat and fish. …
Insufficient Evidence for: …
Fatigue. Early research suggests that taking an energy drink containing taurine prior to driving may reduce driver fatigue. …
Exercise performance. Research suggests that taking 1-1.66 grams of taurine before exercise does not improve overall exercise performance. Using products containing taurine combined with other ingredients might improve cycling performance but not strength training or sprint performance. …
Mental performance. Early clinical research suggests that taurine, in combination with caffeine and B vitamins (Red Bull Energy Drink), can improve attention and reasoning in adolescents, but does not improve memory. …
Taurine is POSSIBLY SAFE for adults and children when taken by mouth in appropriate amounts. Taurine has been used safely in adults in studies lasting up to one year. It has been given safely to children for up to 4 months. …
[But] Not enough is known about the safety of taurine in pregnancy and during breast-feeding. Avoid using it. … There is some concern that taking too much taurine might make bipolar disorder worse. …  (emphasis added)
The same article warns of taurine interactions with lithium, often prescribed for depression and bipolar disorder.
While KETO//OS is likely not dangerous, there are several conditions under which caution should be exercised.
KETO//OS Pros and Cons
Aside from the digestive issues, a lot of folks simply don’t like the taste of KETO//OS. Add in the extortionate price tag and Prüvit’s multi-level marketing (MLM) platform—yep, here we go again—and the cons of this product really start to pile on. And it doesn’t work, or not the way Prüvit claims it does. Users reported headaches as well. The diuretic effects have users in the bathroom a lot. We’re getting neck-deep in cons, now.
Unfortunately, this very expensive product simply does nothing at all. Perhaps it works on selected individuals, but not for me, 58 year old male, 80 pounds over weight. Used in conjunction with better diet and more exercise. I GAINED WEIGHT over 1 month of use. Too expensive for those kind of results. 
The one thing KETO//OS does seem to have in its favor is that it can help folks who are already on a low-carb, paleo, or keto diet to offset the utter misery of “keto flu”—a period of lethargy, often dizziness, brain fog, and a severe craving for carbs—in the early stage of starting such a diet or recovering from a weekend of having fallen off the low-carb wagon.
From a reviewer of a 3-pack of the On-the-Gos (more or less a sample pack, $16.29 at Amazon):
This product is great. I Used this to ward off the keto flu and after a weekend of some bad eating to help get back into ketosis. I like the fact that this product came in a three pack because I know canisters of ketones go for about hundred dollars and this is a great way to try them out before dropping a mint on something you might hate. The orange cream flavor wasn’t bad either. 
NOTE: Often folks who bought from a rep will leave reviews on Amazon, so we use those because Amazon reviews tend to be brutally honest.
The Bottom Line
Overall, what seems to be a really great idea and a cool product is nothing more than a waste of time and money. Marketed as a magic pill and then sucking customers into an expensive, pushy MLM sales pitch, KETO//OS doesn’t do what it claims. It maybe works as a recovery tool for keto-flu sufferers, but even then it’s terribly expensive for any sort of regular use. Cross this one off your list.
Top 5 Diets in 2018*
6 Month MBG
|#1 PS1000 Plan||$$|
|#2 Trim Down Club||$||–|
|#3 Ketogenic Diet||$$$||–||–||–||–|
|#4 Weight Watchers||$$$$||–|
*Individual results will vary.
Articles, reviews and investigations are our own opinion, and written based on the information publicly available or simply contacting the companies. We try our best to stay up to date with constantly changing information. If you find any information inaccurate, please email us, we’ll verify for accuracy and update it.
Disclosure: some of the links on this website are affiliate links. This means that if you purchase an item following one of the links, we will receive a commission. Regardless of that, we only recommend the products or services, that we strongly believe will benefit our readers. Read full disclosure here.”