Updated May 17, 2019.
Published Dec 22, 2016.
Dr. Krystal Crawford, ND, MS
Medically reviewed by Dr. Krystal Crawford, ND, MS, written by Rachel Butler.

Pruvit KETO//OS is an exogenous ketone supplement that promises better mood, strength, energy, sleep, focus, and fat loss. Below we take an in-depth look to see how Keto//OS can benefit the consumer, and whether it will aid weight loss.


  • Money-back guarantee offered


  • Incredibly expensive
  • Poor reviews online
  • Not very effective
The manufacturers of Keto//OS claim that their product causes the body to go into Ketosis without the need for a carb-free diet. Ketosis is a metabolic state where the body’s energy supply comes from ketones in the blood, rather than from glucose (from carbohydrates).

Keto//OS Overview

What you need to know about Keto//OS

The product primarily consists of Medium Chain Triglycerides, which are essentially a type of fat. When they are metabolised by the body, they create ketones, which cause the body to start using stored fat as an energy source.

Ketones that are naturally occurring in the body are not the same as Raspberry Ketones.

We are slightly concerned by the high sodium content of this product. Taking two servings per day would provide 80% of a person’s daily recommended sodium intake before the consumer has actually eaten anything. The manufacturers state that the sodium is present to counteract some of the loss of electrolytes caused due to the diuretic properties of the product.

What are the side effects of Keto//OS?

Ketosis can cause fatigue, brain fog, and even dehydration. It is also often associated with bad breath.

How much does Keto//OS cost?

Fifteen servings of the individual sachets costs $85 plus delivery. Thirty servings of the individual sachets costs $160 plus delivery. A single tub of the product, containing 30 servings, costs $144 plus delivery charges.

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Keto//OS Key Features

KETO//OS (Ketone Operating System) is described by the manufacturers as,

a revolutionary drink mix that is based on a proprietary ketone energy technology that delivers advanced macro nutritionals and promotes optimized cellular regeneration, energy and longevity.

Keto//OS Key Points

  • Manufactured by Pruvit, a Multi-level Marketing company
  • Choice of sizes
  • Auto-ship program offered

It primarily provides medium chain triglycerides but also contains a few other ingredients, such as caffeine.

It is a powder that you mix with 8-10 oz. of water. Within 15-30 minutes it puts your body into Ketosis.

How to Take Keto//OS

Dissolve one heaping scoop or OTG pack in 12-16oz. of cold water and shake/stir vigorously. Can be taken with or without food.
Therapeutic dose = 1 daily serving
Optimal performance = 2 servings AM/PM

Ketones are formed by one of two processes – when liver glycogen stores are depleted, or from metabolising medium-chain triglycerides, which is the main ingredient in Keto//OS. When the body is in a ketogenic state (from having higher than normal ketone levels in the blood), the body begins to break down body fat as a source of energy, therefore increasing the rate of fat burning in the body. Ketones may also help to suppress the appetite.

Keto//OS Concerns

  • Incredibly expensive
  • Poor reviews online
  • Not very effective

What does Keto//OS claim to do?

The manufacturers of Keto//OS provide a huge list of the benefits of their weight loss supplement.

They claim that it will cause:

  • Weight loss
  • Blood sugar balance and enhanced insulin sensitivity
  • Increase satiety, and decreased food cravings
  • Improved energy levels, oxygen capacity, motor performance & athletic performance
  • Mostly due to the impact of ketones on enhanced blood flow, through vasodilation
  • Migraine treatment
  • Neuro-protective benefits in seizure disorders; ADHD; Alzheimer’s disease, memory and cognitive function; Parkinson’s Disease and Multiple Sclerosis
  • Autism and improved behaviour and social impacts
  • Mood stabilization in bipolar disorder (type II)
  • Stroke prevention; cardiovascular disease; metabolic syndrome management; improved cholesterol levels
  • Inflammation management
  • Endurance enhancement

The manufacturers go on to add another description of the product:

  • Is Nutrient and Energy Dense
  • Increases TCA Cycle Efficiency and ATP Production
  • Does Not Contain Insulinogenic Compounds
  • Will Not Promote Lipogenesis
  • Promotes High Nitrogen Retention Protein Synthesis
  • Provides Elevated and Sustained High Energy Ketones
  • Promotes Sustained Energetics
  • Increases Lipolysis for Energy Substrate Utilization
  • Promotes Thermogenesis
  • Provides Neuroprotection & Increase brain activity
  • Promotes Triglyceride Reduction
  • Promotes Enhanced Neurological Efficiency
  • Helps Reduce Blood pressure
  • Promotes Re-balancing of Yeast in Gut (candida)

Does Keto//OS work?

Customers have mixed feelings about the product; they overwhelmingly state that the product tastes awful and so is difficult to drink. Some people did find that their body entered ketosis, but that results did not last for long.

The semi-professional athlete who reviewed the product has confirmed our suspicions about the product; it will not aid weight loss through causing ketosis on its own, as the ketosis is short lived. However, it could be used by consumers who are already following a keto diet to ‘bump’ up their ketone levels slightly.

Although the manufacturers claim that you do not have to change your diet to see any benefit from this supplement, we believe that without adopting a keto diet in combination with this product, consumers will not lose any weight whilst using Keto//OS.

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Keto//OS Ingredients

The ingredients used in Keto//OS are listed below. The manufacturers do not provide any individual ingredient quantities. The product is also available in a caffeine free version. Each serving contains 110 calories, 970 mg of sodium (40% RDA), 50 mg of potassium (1% RDA), calcium (85% RDA), and 7 grams of saturated fat, as well as some other vitamins and minerals in small quantities. The product contains milk ingredients.

  • MCT Powder (medium chain triglycerides powder): The process of metabolising Medium Chain Triglycerides releases ketones into the bloodstream, which can promote fat burning in the body, to use the fat as an energy source – this is called ketogenesis. Ketogenesis can also be achieved by consuming a carbohydrate-free or low-carb diet, as this depletes glucose levels in the body’s cells, forcing the body to turn to its stored fat as an energy source. Source
  • Beta Hydroxybutyrate
  • Malic Acid
  • Stevia
  • Caffeine: Numerous studies have shown that caffeine boosts energy levels and alertness, as well as mildly boosting the metabolism. The effects shown in studies are small, and some studies are inconclusive. Source

Keto//OS Side Effects

Ketosis can cause fatigue, brain fog, and even dehydration. It is also often associated with bad breath.

The manufacturers of Keto//OS have provided the following description of potential side effects in an FAQ document:

Supplementing with Keto-OS or following a ketogenic diet can cause a slightly diuretic effect, and can deplete magnesium, potassium and sodium stores. This problem can be rectified by supplementing with a good electrolyte or increasing the sodium in your diet. However, Keto-OS adds additional sodium to the formulation to counter-act this sodium depletion. Keto-OS is formulated with medium chain triglycerides, which can often cause digestive distress. Gastrointestinal complaints may occur because your body has not yet adapted to the increased fats in your diet, and is less efficient at utilizing ketones as its fuel source. Once the body has adapted to this increased fat in the diet, the digestive distress should resolve. We recommend to start slowly and build up to a full serving twice a day, but it is totally up to the individual.

Caution: As with any new supplement, consult with your physician before using. If you are using any prescription or over-the-counter medicines, are unaware of your current medical condition, have any pre-existing medical condition(s), have hypersensitivity to salt or have any risk of kidney stones, consult with your physician before using this product. Build up to a full serving slowly to avoid gastrointestinal discomfort. Not suitable for those under the age of 18. May not be suitable for pregnant or breastfeeding women.

Keto//OS Customer Feedback

The product is currently being resold on Amazon, where numerous customers have left reviews. These are generally negative reviews, with 68% of reviews being rated three stars or less. The majority of customer reviews are not verified purchases, and one commenter claims that they are fake negative reviews written by competing companies.

Overpriced and unnecessary. You can eat ketogenic for free. This product is very new and unregulated. Not to mention a MLM pyramid scheme company with little ethics.

This product was absolutely awful! Taste was good but I took 1/2 a packet and 15 hours later I was still wired and jittery from it. My heart was racing and I truly was concerned for my health. NEVER AGAIN!

This Keto product tastes a lot better than the KetoCaNa or KetoForce. It is so much easier to get down. Don’t get me wrong, it is not wonderfully yummy. It is effective and WILL get you in Ketosis in an Hour…it did for me in 30 min.

I so bad want to like this, but it’s so hard for me to swallow. I’m going to try mixing in it with some other drink soloution to see if I can drink it

I used this to help me achieve ketosis. I measured my ketones and they came up, but the results did not last at all. Also, to me the taste was too strong: too sweet and too much flavor. Very expensive too.

Tastes like 1000 baby aspirins crushed up into a powder. It made me sick to the stomach trying to get down just half of it.

Terrible taste. Made me feel ill for hours until eating something

I am a semi professional athlete and have been in ketosis for a couple years. Although, I have never been overweight, I use for ketosis for its health and mental and physical performance benefits while under stress from competition. ..I find Keto-OS bumps my ketone levels up and extra 1-2 mm as measured by blood. I see it as an assist to the ketogenic diet, not something to use while eating a crappy diet and hope this helps you get into ketosis. I think the taste is fine . The caffeine version is not too much caffeine for my body. During a competition weekend I use 2 per day..The caffeine version in the afternoon. Its also easy on my stomach, unlike MCT and coconut oil.

Keto//OS Money-Back Guarantee

Keto//OS is covered by a 100% 90-day money-back guarantee.

Pruvit offers a one hundred percent (100%) ninety-day money-back guarantee for all Customers.

If within the first 30 days you are not satisfied with the product they may contact [email protected] to return the unused portion of the product for a refund. If within days 60 to 90 you may contact [email protected] to return the product for a refund if the products are in resalable condition.

If a Customer purchased the product through a Pruvers website and is not satisfied with the product they may contact [email protected] to return the items for a refund if the products are unopened and in resalable condition. If the Customer purchased the product directly from a Pruver the Customer may request a refund directly from their Pruver.

Where To Buy Keto//OS

Keto//OS is available from the Pruvit official website, Privitnow. There are two forms of the product, a tub containing a month supply, which comes with a scoop. These products are sold under the code KAN.

There is also the ‘On-the-go’ packets of KETO//OS, described as ‘Easy to carry with you and drink anywhere.’ This option is sold under the code OTG.

Fifteen servings of the individual sachets costs $85 plus delivery. Thirty servings of the individual sachets costs $160 plus delivery. A single tub of the product, containing 30 servings, costs $144 plus delivery charges.

An order of 60 servings, which consists of a tub of the product (30 servings) and 30 on the go sachets, costs $300 plus delivery charges.

The largest option is called the Go pack. This contains 75 servings, made up of one tub of Keto//OS, and 45 on the go sachets. This option costs $389 plus delivery charges.

A ‘Smartship’ program, (essentially an auto-ship program) is also offered, with savings on each delivery. Customers will then receive the product every 30 days. Despite the discounts offered, this option could work out as much more expensive, and although the company claims that consumers can opt out at any time, auto-ship programs are often difficult to cancel.

Keto//OS is also available on Amazon. Here three servings are offered for $21.97 plus delivery charges.

Watchdog Verdict

Keto//OS is, in our opinion, an overrated product that does not aid significant weight loss. It could help dieters following a keto diet plan to boost their ketone levels, but in combination with a regular diet, it is unlikely to have much, if any, effect upon fat burning and weight loss.

This product is incredibly overpriced for what is essentially a medium-chain triglyceride supplement. It is covered by a 90-day money-back guarantee, but a closer inspection of the terms and conditions shows that really there is only a 30-day money-back guarantee, with returns on unopened products being available for 90 days after purchase.

Customers interested in this product should instead consider following a calorie restricted low carb or carb-free diet plan that is designed to induce ketosis, rather than rely upon an overpriced supplement.

Overall, we do not recommend Keto//OS to our readers.

How does Keto//OS compare to Phentaslim?

Criteria Keto//OS Comparison Phentaslim comparison
Clinically Proven Ingredients
Side Effect Free
Positive Customer Reviews
24/7 Support
Money-back Guarantee

Disclaimer: Our reviews and investigations are based on extensive research from the information publicly available to us and consumers at the time of first publishing the post. Information is based on our personal opinion and whilst we endeavour to ensure information is up-to-date, manufacturers do from time to time change their products and future research may disagree with our findings. If you feel any of the information is inaccurate, please contact us and we will review the information provided.

Have Your Say

12 comments on 'Keto//OS'

  1. I disagree with your review of Keto/OS. I have been using the chocolate swirl powder for about 6 weeks and have lost almost 30 pounds. I haven’t really increased my physical activity. I am trying to restrict my carb intake to <50g/day. I think Keto/OS is a big part of my weight loss. Yes, it is expensive. Yes, it's hard to obtain because you need a referral to buy the product. For me it has been worth it. I think what it comes down to is everyone is unique. What works for one person may not work for another. You need to try different products until you find one that works for you as an individual. I was lucky and Keto/OS was the first product I tried and it worked for me. Good luck to all of you with your weight loss!

  2. Keto//os has been hugely impactful in changing my life. I have tons of energy, more focus, losing weight, my anxiety is all but gone.
    While being a bit pricy, is not unreasonable in terms of health products, and it’s not claiming to be a “magic weight loss solution” that is simply a side affect you may experience.
    They do suggest you stay hydrated while using it, but no more than you ought to anyway. And I love the flavor, all of them. This product is delicious, if a particular flavor doesn’t suit you, try a different one, the chocolate swirl in milk is my favorite.
    This product is amazing and worth every penny.

  3. Keto / OS has changed my life! I no longer have migraines, my dr took me off of lipitor, my bp is a non issue, I don’t have night sweats any more! Did I mention that I am finally losing weight as a side benefit? Keto/OS is not a weight loss product. It is a Ketone fuel source. If you go to the Pruvit website, you will find videos from the Science and Medical Researchers, Doctors, Athletes, and the like explaining why and how Keto/OS WORKS! ON Wednesdays, there is a LIVE Q&A online with a Doctor. If you’re on the fence, go to their website and watch all of the videos. It will enlighten your knowledge, then you can make an informed decision.

  4. These companies prey on desperate people. I know I used to be one of them. I tried everything! And then, when I had enough, I tried the one thing I hadn’t; Properly portioned meals that met my nutritional needs and regular exercise that included weight training and cardio. It’s been just over 8 years and I’ve been able to maintain the same weight and size-130lbs down from 250. It was very difficult at first and I wanted to give up, I cried during the workouts and I was sore. But, it worked, and continues to work. It can work for you too. There is no magic pill or “diet” that does what sensible eating and exercise can do. Just try it consistently for 6 months. You will see, it works and pills don’t and “magic” drinks just don’t.

  5. This product has dramatically changed my life. It’s given me the energy and mental focus to take my life back. I have two young children so energy is a must that I’ve been lacking. I already drink plenty of water, and even more now, so I never experienced any dehydration although I can see how it could cause it. But as far as any “side effects” I have better mental clarity and more energy than I’ve had since before high school. I’m slowly adapting a Keto diet to aid in my weight loss and so far, my clothes are starting to fit me again. Not to mention that with the extra energy I have, I’ve been able to workout again.

    I’ve read some comments on this at those who have had a negative experience and most could have been avoided with proper research first. If you have a medical condition that causes you to have to avoid certain foods…talk to your doctor first. If you start feeling dehydrated…drink more water.

  6. Keto OS has made profound changes to my muscles and pain. Increased my brain capacity and energy and allowed me to start being active Again instead of debilitated.
    It’s an all round winner

  7. It does taste nasty. Like gagable nasty. I’m only doing one a day and I knew lots of water was needed. Haven’t experienced any of the above. Is way over priced

  8. I just came from the emergency room because I had a migraine so debilatating that I could not open my eyes without vomiting. I did a five day trial of Keto OS and have been off of it for two days. My blood pressure was very elavated. I have ALWAYS had low blood pressure. My electrolytes are so out of balance that I required iv hydration despite drinking nearly four liters of water a day while taking this product. I can not recommend this product to anyone. The most alarming thing to me was that, despite the trip to emergency and my health issues, the rep kept trying to convince me that it was normal and safe to continue!

  9. This stuff is NASTY! I tried it and threw up. They don’t have a phone number to call to get my money back. What reputable company doesn’t have a phone? I wish I’d researched this before I bought it, lesson learned. Didn’t realize drinking this could kill my kidneys! It’s not worth it. Was telling my coworkers not to order this and one told me about Saba ACE, a weight management and energy supplement. Reviews are awesome, it’s had clinical studies and is even sold in Canada, which is very hard to get into. Best part is a month supply is only 40 a month.

    1. There is more bad reviews on Saba products then Keto//os. Most of the time people are dehydrated from drinking Keto os because it makes you drop a lot of salt until body adjusted to change. I personally had massive dehydration headaches-i thought it was the worse thing I ever experienced. However, I did my research and was prepared, I was drinking salt (3g-5g), electrolytes and taken magnesium tablets. I only had one bad day, and another one, but after that I feel great. I also, kept-adapted so I don’t actually require to take KETO//OS to elevate my ketones, but I do when I go to the gym for ultimate fat burning and muscle recover. The product works, however people who are selling the product do not understand it/ and do not explain the DO’s or DONT’s – because they just don’t do research. Information should be provided to customers so they know exactly what they getting into!

    2. Hi Ron, you say that the people selling the product don’t tell potential customers how to take the product – are you able to shed some light on this for me please.

      I see you say something about electrolite and magnesium – does this help with the adaption? I’d like to try the product, but would like to do it properly.

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