There are two burning questions when it comes to exogenous ketones. Who has the best exogenous ketones? And do you need them? To answer this question I decided to do my own exogenous ketones review.
There continues to be a ton of discussion about exogenous ketones on Instagram, Reddit and elsewhere. Especially on Instagram, the topic is quite contentious.
In one camp we have those that use exogenous ketones and believe they help them with their health goals. Most of these people focus on the mental and health benefits of exogenous ketones. However, many of them are also promoters for Pruvit or other brands and make money when people purchase their products. That is a bone of contention with a lot of people who feel they can’t be sure of people’s intentions.
On the other hand, there are those that know the body makes endogenous ketones when a strict keto diet is followed, and thus there is no need to purchase a ketone supplement when your body makes ketones for free. They also believe that the body will burn the exogenous ketones first before burning the body’s endogenous ketones thus slowing weight loss.
This argument could have some validity but ignores that weight loss might not be the goal. It also doesn’t take into account that exogenous ketones have an appetite suppressant effect that could contribute to weight loss.
What Are Ketones?
If you found and clicked on this article, you probably already know what ketones are. Let’s just do a quick review to make sure we’re all on the same page. Ketones are an organic compound that can be used by the body for fuel. The ability of the body to produce ketones was a huge beneficial adaptation in evolution that allowed humans to go for days without food but still remain sharp and energetic do so they could eventually find or catch food.
Contrary to popular belief, NO amount of carbohydrate consumption is required for the human body and brain to function optimally. Your liver has the ability to create all of the glucose the body and brain needs through a process called gluconeogenesis.
Ketones can supply up to 70 percent of the brain’s energy1 and exciting research is finding damaged neurons that can no longer process glucose can still process ketones!
Endogenous vs Exogenous Ketones
Clarifying exogenous and endogenous ketones is pretty simple. Exogenous ketones are a supplement and come from outside the body. The type of ketone in these supplements is shortened as BHB for beta-hydroxybutyrate. Endogenous ketones are the ones your body makes itself when you practice a ketogenic diet or when fasting for an extended time.
Ketones in general have been a topic of interest of mine for a while. Way back in what seems like another lifetime, I was in graduate school for clinical neuropsychology. While I didn’t finish the program, the interest in brain function has always stuck with me.
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The Ketone Discussion
Click here to skip the research and go right to the exogenous ketones review. However, I highly recommend you read the entire article!
There are a few subtleties on both sides of the exogenous ketone argument that go mostly undiscussed. For example, what about people that have trouble getting into ketosis? What about people that may need a higher level of circulating ketones in order to combat disease? What about those that may lose more weight with exogenous ketones because their appetite is suppressed and hunger hormones are balanced by supplementing with the best exogenous ketones2? Is making money from a product that you believe in inherently wrong? What about people that may not want to eat very low carb all the time but would still like to experience the benefits of ketosis?
I’m all about the science and that is where we are about to dive in! Since I do personally practice a strict keto diet and am in ketosis all the time, I was skeptical about the need for exogenous ketones. However, I knew trying them was really the only way to know for sure whether they would help me.
The purpose of this article is three-fold, to give the scientific reasons you may want to experiment with supplemental ketones, to show what brands sell the best exogenous ketones and to give you my personal experience with taking them.
Why Would You Want to Try Exogenous Ketones?
If you’re looking for reasons to try exogenous ketones, there is a lot of research to back them up. Of course, adopting a ketogenic lifestyle is best but what if you’re unable or unwilling to do that? I’d rather see people improve their health by any means possible and if that can start with a drink rather than a big diet change, I’m ok with that.
That’s one of the reasons why I’m doing an exogenous ketones review to start with…to see whether this supplement has the ability to have people experience ketosis outside of diet.
There are so many people entrenched in eating the standard American diet. Many also still believe the government has their best interests at heart in regards to diet. You may not be able to convince them otherwise, but you might be able to get them to try a new drink (enter exogenous ketones). If people can experience ketosis, maybe it acts as a motivation to change their diet as well.
As always, consult your health or medical provider before deciding to take any supplements. The information contained here can not substitute for or be construed as medical advice. I am not a medical professional.
By the way, if you want to learn more about how our dietary guidelines (based on no good science) came to be, read The Big Fat Surprise.
There are several things that ketones can do for your health, whether your body makes them or whether you supplement with them.
Antedoctal reports from those in a state of ketosis include greater mental clarity and focus, weight loss, better sleep, decreased inflammation, appetite suppression, migraine management and increased sports performance among other benefits.
These benefits are backed by research either on ketosis through diet or fasting, exogenous ketones or both.
Like all research, some ketone studies have the common issues with extending research to the general population including confounding variables, small sample size and research generally being done on males or only animal models.
Purpose of Exogenous Ketones Review
This article is not meant to be a comprehensive review of the existing research. It’s all fascinating but that would bore you to tears if you’re not a researcher! However, that is what actually has to be done for real research. Did you know every time someone publishes a paper they have to try to dig up all previous related research first? One of the fabulous things I learned in grad school.
If there is a particular area in which you want to take a deep dive, all you need to do is search ketones, exogenous ketones, ketosis, keto diet, etc. on PubMed. That’s where you can find peer-reviewed, published research, not just someone’s opinion. You’ll come up with plenty.
The research on the role of ketones is in its infancy but there are a lot of promising results.
As more comes to light, there will likely be more companies that want to get involved in funding research and selling ketones. There is money to be made in telling people they can be helped by drinking a supplement rather than changing their diet.
While there are some companies such as Real Ketones funding consumer studies, there are others that just rely on the research already being produced by the scientific community.
For that reason, finding trusted resources for your exogenous ketones is important. As they get more popular, exogenous ketones will likely experience the same issues that exist in the rest of the supplementation market…poor quality, possibly contaminated, etc.
The answer to this question is a personal one, and of course, depends on a few factors. Ketones are approved for use in adults. If you don’t mind taking a supplement and you can afford them, then the short answer is why not try them and see for yourself?
There are certainly benefits to be gained and everyone’s response is individual. As in many things, what works for you may or may not work for someone else. The only real way to know is to try it.
Hopefully, this exogenous ketones review will help you make that decision.
Do you need exogenous ketones? If you’re relatively healthy, maybe not. However, if you want to OPTIMIZE brain function and performance beyond nutritional ketosis, or if you’re insulin resistant or fighting disease they may help you with your health goals.
Getting into Ketosis
A recent study looked at the metabolism of exogenous ketones in healthy subjects3. They found ketone drinks lowered blood glucose, free fatty acid and triglyceride concentrations and concluded exogenous ketones are an efficacious way to get into ketosis (remember, ketosis is a metabolic state, not what you eat).
This research concluded that drinking ketones were a viable alternative to diet in the ability to maintain ketosis4.
Although many of us are fine with modifying our diet to a point where we enter the metabolic state of ketosis, it’s not always possible for everyone. The inability to keep one’s diet low carb diet for any reason or severe insulin resistance, both make it difficult to get into ketosis.
Exogenous and Endogenous Ketone Research and Benefits
The ketogenic diet has been used to treat epilepsy for decades. Recent research is using exogenous ketones to see if they have the same anti seizure effect.
“As of now, the research is in its infancy; performed primarily in experimental animal models. However, the results from these studies are promising. In various epilepsy and seizure models, ketone ester, ketone salts, and MCTs have shown anti-seizure effects. Because exogenous ketones allow for a rapid induction and level of ketosis that mimics that achieved with KD treatments for epileptic seizures, it is possible that patients would benefit from these supplements in a variety of ways,” reported the Charlie Foundation.
This research specifically on exogenous ketones released in 20185 found that exogenous ketones decreased plasma insulin(fat storage and glucose modulating hormone), ghrelin(the hunger hormone), GLP-1, and PYY levels were significantly lower 2 to 4 hours after consumption. These decreased hormone levels could lead to appetite suppression.
Note that ketones levels during this experiment were around 3.3 millimoles (mm). This is not a level easily achieved by most people unless they’re fasting for an extended amount of time.
This is why people may experience fat loss when supplementing with exogenous ketones. They support internal hormonal changes that in turn make it easier to experience the hunger cues of a healthy metabolism rather than a damaged, insulin-resistant metabolism.
The best exogenous ketones for this purpose are ketone salts such as Pruvit, Real Ketones, Ketoned and Perfect Keto. Ketone esters (even more expensive and taste like jet fuel) seem to have a greater role in athletic performance but for appetite suppression and other benefits, drinking ketone salts works fine.
A group of healthy men experienced greater fat oxidation during exercise after ingestion of exogenous ketones but also some degradation of performance with high-intensity exercise6. This decrease in performance is consistent with anecdotal evidence that exercise performance generally suffers when first starting the keto diet.
Ketones may also help with fat loss through the mechanism of reducing glucose so that hormones stay balanced7. Since insulin signals the body to store fat, anything that helps keep blood glucose and insulin low is a potential help to fat loss/weight management.
The ability for ketone salts to lower blood glucose8 also has great implications for diabetes management.
Thought Leader and Top Researcher on Uses of Exogenous Ketones
From Dr. Ryan Lowery specifically on exogenous ketones only (this whole interview is worth a listen),
And I think it’s been refined since of understanding like, it’s not a magic supplement, it’s not going to magically melt body fat off of your body. If you’re talking about general health to your point of like inhibiting HDAC and somebody’s longevity, there’s a possibility that ketones themselves, there are studies, like in the C. elegans, they were utilizing just exogenous ketones.
They weren’t putting them on a certain diet, they were utilizing exogenous ketones. We’ve done studies in animals, utilizing both a combination of a ketogenic diet and exogenous ketones and saw a slightly better result for like things like increasing brown fat, decreasing food deficiency, which is the amount of weight you gain over the amount of food you consume. So, for general health that’s really the application.
This area has a lot of research and is showing the most promise with endurance exercise, mostly with ketone esters. Exogenous ketones and can increase performance9 In highly trained athletes10, exogenous ketones increased performance even in the presence of glucose.
What about the argument that ingesting exogenous ketones slows down fat loss?
“Given the saturation kinetics of KB oxidation by skeletal muscle and curvilinear relationship between oxidation and plasma concentrations, it is likely that there is an optimal range for performance benefits. At present, we speculate that this exists between 1 and 3 mm βHB11.
I’d love for someone else to interpret this one, but to me, this appears that the theoretical limit is 3mm for muscle utilization of ketones. This doesn’t even take into account how much ketone your brain is using for fuel. Since most people that aren’t fasting have blood ketone levels between .5 and 1.5 this seems to make the case that the body will not only use the ketones your body is naturally making but also have room to utilize exogenous ketones as well.
This argument also ignores the appetite suppression that comes with ingesting ketones. If a person is able to extend their fast or eat less by ingesting ketones, the net effect will be fat loss.
Effects of Ketones on an already Fat Adapted Person
This was an interesting observation by Dr. Peter Attia. He is keto/fat adapted and experimenting with exogenous ketones,
In addition, the body regulates ketone production via ketonuria (peeing out excess ketones) and ketone-induced insulin release, which shuts off hepatic ketogenesis (the liver making more ketones when you have enough). The insulin from this process could be increasing glucose disposal which, when coupled with PDH activation, could drive glucose levels quite low.
If that explains the hypoglycemia, it would seem the absence of symptoms can be explained by the work of George Cahill (back in the day; see bottom figure in this post)—when ketone levels are high enough they can dominate brain fuel, even ahead of glucose.
Finally, these compounds seemed to have a profound impact on my appetite (they produced a strong tendency towards appetite suppression). I think there are at least two good explanations for this…appetite regulation—is too interesting to warrant anything less.
So what all this means to me is that even when in nutritional ketosis, there is the ability for the body to utilize more ketones if they were available and any extra is excreted, similar to the way our body processes vitamins.
Because glucose metabolism is impaired after traumatic brain injury, ketones could be of great benefit in recovery12. Ketones are the only known alternative to glucose for cerebral metabolism.
There is also evidence that ketones can help an aging brain13. Both aging and diseased brains display impaired glucose metabolism to different degrees.
Dr. Lilianne R. Mujica-Parodi is finding that while the brain’s ability to utilize glucose continues to decline with age, the ability to metabolize ketones for fuel is unchanged14. I had the privilege of hearing her speak about this in October and the implications for using exogenous ketones to treat dementia as well as normal age-related brain function decline are huge.
The Aging Brain
She said that a huge decline in cognitive function occurs between the ages of 47 and 72 due to brain network destabilization. After just one week in ketosis, brain networks stabilize in part because ketones provide 22 percent more ATP (energy). One of the most exciting things I heard was that their lab showed this effect could be duplicated with exogenous ketones. This means someone with cognitive decline that can’t or doesn’t want to adhere to the ketogenic diet can still be helped!
Based on her research, aging brains naturally have an energy gap and ketones can help bridge that leading to better cognitive performance. If you’re over 40 and not willing to go keto, this could be one of the best arguments for trying exogenous ketones.
If you can wade through it, this article15 has a fascinating discussion on brain function, energy sources, normal aging brain and dementia. Alzheimer’s disease is now being thought of as type 3 diabetes. Sugar consumption and ketones have amazing implications in brain health.
I also heard Dr. Mary Newport speak which I was very excited about. I previously heard an interview with her on a podcast and it was absolutely amazing. She greatly impacted her husband’s Alzheimer’s disease through the use of MCT and coconut oil. Alone. You read that right. She has now helped hundreds of others do the same and believes exogenous ketones help as well.
The blend of MCT and coconut oil she used to fight Alzheimer’s disease in her husband is sold at this link.
All of her books are now on my reading list, but first up is The Complete Book of Ketones.
Promising results for ketones acting as an antidepressant16.
There is quite a bit of research in this area as well. Dominic D’Agostino and Thomas Seyfried are two of the most prominent researchers in this area. One of D’Agostino’s is recent papers concluded that ketone supplements may be useful as an adjunct or alternative to the ketogenic diet17.
Numerous podcasts have interviewed both doctors. If this is a topic you’d like to hear more about, I recommended listening to some of those interviews.
One of his recent studies in animals showed decreased tumor cell viability and prolonged survival [enf_note]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4235292/[/efn_note].
Seyfried uses the Glucose Ketone Index (GKI) as a tool for therapeutic ketosis in the management of cancer. The GKI is the ratio of blood glucose to ketones. Divide blood glucose in mg/dL by 18 (to convert to mm) then divide by the blood ketone level in mm. to get the GKI. For cancer therapy, the value they are looking for is around 118.
If you’d done any extended fasting, you’ll know this GKI is very difficult to hit…even in a very insulin sensitive person. This is where supplementing with exogenous ketones could be of real benefit.
There is plenty of anecdotal evidence and research19 that shows the ketogenic diet helps migraines. There is also a randomized clinical trial20 underway in 2019 to test exogenous ketones as a treatment for migraines.
The ketogenic diet is very anti-inflammatory and helps with blood glucose control. Some evidence is showing just drinking ketones to have an effect on blood glucose as well21. Ketones themselves are anti-inflammatory22 and promote decreased inflammation in the body. A very low carb keto diet outperformed a low carb diet in reducing inflammation markers23.
Too much inflammation is highly related to many diseases, including heart disease.
Who Sells the Best Exogenous Ketones?
In typical in Heal Nourish Grow fashion, I wanted to explore the research on this for myself and try a few of them for myself. As of this writing, I have been strict keto for almost three years and low carb for four. I had never tried exogenous ketones until September 2019 when I decided to do this exogenous ketones review and experiment.
However, I’ve known about them in a very personal way for a couple of years. My sister has been taking them for a while and swears by them. I don’t know about you, but I’m much more likely to believe the claims of a close friend or family member when recommending a product.
All exogenous ketones were purchased with my OWN money and this was an expensive undertaking. I tried Pruvit, Real Ketones, Ketoned and Perfect Keto, all of which are well-known brands. Pruvit has several patents on exogenous ketones as does Real Ketones.
Do Exogenous Ketones Work?
If you want to know whether the best exogenous ketones on the market “work”, you first need to define what “work” means. Since the point of exogenous ketones is to raise your blood ketone level in that sense they all worked. At least for me.
Blood ketone levels with all of the supplements were raised .5mm to 1.5 mm over my baseline reading. In my body, Pruvit ketones raised my levels the most. An hour after drinking, my blood ketone levels were generally at least 1mm higher than baseline. They also lasted the longest with elevated levels at the six-hour mark.
Pruvit ketones are bioidentical and naturally fermented. According to the company website, “with patent -pending KetoNAT™ BHB salts, facilitates quick absorption of ketones which allows a state of ketosis to be reached faster than ever for unrivaled results.” Perhaps this technology allows better absorption of its exogenous ketones than others. Real Ketones product is also bioidentical.
If you’re defining how ketones “work” in some other way then your conclusion my be different.
What Do Exogenous Ketones Do for Normal People?
Many of the studies mentioned above look at using ketones for various diseases and conditions. But how do ketones work for normal people? For that, you can look at the results from the athletic studies and research on normal volunteers. Companies selling ketones promote the following benefits.
- Supports healthy cell function
- Rapidly repairs DNA
- Boosts immune function
- Elevates essential amino acids necessary for optimizing body composition
- Manage weight
- Maximize cognition
- Feel more energetic in a low carbohydrate environment
- Acts as a “brain tonic”
- Offers glucose control support
- Enhances overall performance
- Improves general overall health
- Curb appetite during intermittent fasting
- Energize you through the afternoon slump
- Fuel body with ketones
- Ease transition to ketosis
- Combat keto flu symptoms
When attending a recent conference, I spoke with several people about exogenous ketones. Between those conversations and anecdotal evidence online, the most common effects of exogenous ketones include weight loss, better sleep, more focus, more energy, better workouts and appetite suppression.
My Personal Experience with Drinking Exogenous Ketones
Since deciding to write this exogenous ketones review, I’ve tried six different exogenous ketones.
What I have experienced personally while supplementing with the best exogenous ketones (leaving out the two that weren’t in the “best” category) is blood glucose reduction, appetite suppression and more focus.
I was really hoping for the more energy bonus but I have yet to experience that one! I’d describe what I experienced on that front more like non-jittery focus rather than any discernible energy.
For the record, I’m in ketosis all the time already through my strict diet so the benefits I experience may be more blunted than for those who eat more carbs or have been in ketosis for a shorter amount of time.
Which Brand Has the Best Exogenous Ketones?
This is obviously a subjective conclusion based on a number of factors. First, I am looking at how I felt after consuming, Next, I’m considering the taste (some exogenous ketones definitely taste WAY better than others) and price.
Exogenous Ketones Review: Price
In general, ketones are fairly expensive. However, when you put this cost in the context of taking other dietary supplements or in place of a daily Starbucks, exogenous ketones definitely seem more affordable.
As you can see, based on price alone, Real Ketones is the clear winner.
Exogenous Ketones Review: Taste
It’s fairly common for some people to dislike the taste of ketones. After all, it’s a lot of minerals and salt and can taste like that. Just be thankful we’re not experimenting with ketone esters here, just the salts. I’ve heard numerous people say ketone esters taste like rocket fuel and make them gag! I would like the taste of ketone salts to something more like an electrolyte drink.
Fortunately, ketone salts are much more palatable! So who has the best exogenous ketones based on taste? For me, this was extremely easy to judge. Of all of the ketones I reviewed, Pruvit won the taste category easily. The least expensive brand, Real Ketones was my runner up.
All of the ketones I tested taste fairly strong. With the recommended amount of water on all of them between 10 and 16 ounces, there is a somewhat salty taste. None of them were undrinkable, but some were not exactly pleasurable except for Pruvit ketones. I genuinely like the taste of its flavors although using the recommended amount of water it tastes way too sweet to me. Mixed in 26-30 ounces of water Pruvit ketones are very tasty to me. It comes out with new flavors and special editions quite often.
You can also mix ketones with other beverages. Try almond milk or use them as a zero carb cocktail mixer.
Exogenous Ketones Review: Effect
So what about the effects of the best exogenous ketones on the market? You’ve already read the research and some of the experiences I’ve read and heard personally from others. But this review is about my personal experience, so boiling it down again…for me:
- Reduced blood sugar
- Non-jittery alertness
- Increased focus
- Appetite suppression
All of these effects are on top of what I already experience from the ketogenic diet. I’m in ketosis all of the time. I suspect for someone who isn’t as strict with their diet they might notice more of an effect. Over time, the combination of increased blood sugar regulation and appetite suppression could lead to some additional fat loss. Fingers crossed!
For the way I felt after taking them, my favorite exogenous ketone was Pruvit. It was the most balanced and kept my ketones elevated for the longest. It was also the one that raised my ketones the most for the longest amount of time, up to 2.5mm more than baseline measurement for up to seven hours, depending on what I had eaten as well.
Ketond made me feel a bit more jittery. The other brands raised ketones for varying amounts of time up to about 1mm and 4 hours maximum.
Exogenous Ketones Review: Overall Winner
Since Pruvit ketones provided the most elevation of ketones in my body for the longest amount of time and tastes great, I give them the top position in this review despite the higher cost. It was also the only ketone supplement that reliably lowered by blood sugar and the one I felt best on.
Both Pruvit and Real Ketones claim to be bioidentical to endogenous ketones. While I wasn’t able to find anything in the research about whether bioidentical is critical, but it did seem like these two provided the most effect in my body.
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