Ketones and the metabolic horse.  A topic that appears to have become popular with many, creating some contradictions in their own current understanding, and stirring up some debates in other areas. I am writing this article today in response to a press release put out by a well known equine insulin resistance group, finding problems with my past articles regarding ketosis, the ketogenic diet and the horse.  My goal here is not to create commotion, but more to relay my understanding, how our approaches came to be, and therefore open the door for understanding of what could be and the possibilities at hand. 

The ketogenic diet is well-known in the human side of weight loss and metabolic support.  While this approach does not apply to the horse, for various reasons, some pieces or components of the ketogenic philosophy do warrant investigation for the EMS patient. Never dismiss a piece of information just because there is not research to back it up, for all thoughts have to start somewhere, and that piece of information that you may have dismissed could be the missing link.

I have written 4 articles on another website outlining the problems present with the typical equine metabolic syndrome patient, which can be viewed here in the respective links:

  1. EMS Horse Part One
  2. EMS Horse Part Two
  3. EMS Horse Part Three
  4. EMS Horse Part Four

While these four articles outline my thoughts and approaches, there is need for clarification, as some are dismissing the potential that these therapies offer for these and many other equine patients. So, for clarification purposes, let me outline from beginning to end as to how I have come to the conclusions that I have.

Let me first state that many are seeking research data to back up or justify any approach in the horse or other species.  While research data is nice and helpful, in most instances of the horse, there is not much research data specifically pertaining to the horse regarding many issues.  However, there usually is research data pertaining to other species, which can be applied to the horse, and then assess the end result and impact.

As a veterinary clinician myself, much of what I have applied to my patients does not have research data.  This applies to medications utilized and even surgical approaches.  In most of those cases, I used what has worked in past cases, or has worked for another colleague, applying that in faith to my patients. Some would show response, while others did not.  These results are true even when we do apply research data specific to the horse.  Whether the research is on a medication, a diet, or a supplement, often the real-world results are not the same as those found in the research study.  That is a fact of life and the reasons for these results should be obvious.  Real life and the real world differ tremendously from controlled research studies.

20 years ago the impact of the diet on the incidence of colic was not recognized and to most clinicians, mentioning a connection was seen as pure insanity.  Move forward to today, and diet is clearly a connector in the incidence of colic and the horse.  Going back to 2006, I was told that there was no way that an herb, such as Curcumin, could impact osteoarthritis and lameness in the horse.  I was told there was no research data and that absorption was very poor.  Well, in that same year, we did our pilot study with the assistance of MD Anderson Cancer Research Facility, demonstrating a marked reduction in synovial fluid inflammatory proteins, a marked improvement in clinical lameness, and all with a barely detectable level of curcuminoids in the blood stream.

For most of my equine and companion animal patients, I rely on diet and herbal therapies to obtain results.  The reason for this is that for most, medical approaches have not worked or provided results, so I choose to get to the root of the issue at hand.  I do apply research, but most of that research is not in the equine species, but extrapolated from others.  One can argue that a horse is different from man, and while this is true on some levels, for the most part, we function pretty similar.  Thus, it is common to see the same end results with herb usage, when utilized properly.

When it comes to the state of nutritional ketosis in the horse and the ketogenic diet, I have experienced some interesting clinical research findings.  My data is not published, but is no different than a doctor making observations over a period of time with patients and their therapies.  I am noting what appears to work in some horses, providing benefits, and thus, to me, it is something that should be explored.  I am not advocating that a state of nutritional ketosis or a ketogenic approach is the answer to equine metabolic syndrome.  To provide the cure or solution to any medical condition would be to discover the cause, and then correct it.  The cause of equine metabolic syndrome,  in my opinion based on my 25 years of clinical experience, is man-made.  This implies that we, as man, are the creators of this condition.  This is no different than metabolic challenges in humans, or diabetic states in companion pets.  We are to blame.  There are cellular changes that have occurred, which create the health challenges, but we are the creators of those changes through our choices of diet, lack of exercise, and other lifestyle changes.  So to truly cure the condition of equine metabolic syndrome, we would have to address us, as the human factor.

A state of nutritional ketosis or a ketogenic approach is just one tool in the chest that could be utilized and proven beneficial for some horses with EMS.  It should be used as a last resort type of measure, when all other factors have been addressed from diet, to exercise, proper foot care, and lifestyle.  These are the most important and one cannot override their effects with any medication or supplement.  In regards to the insulin support group for horses, we do agree on the basic philosophies of managing an EMS patient, so there should be no argument there.  The usage of exogenous ketones and MCT oils is just one option that I am posing for those horses in which measures have been applied, but have failed to produce adequate results.

Here is how the whole investigation on ketones got started.

Several months ago, in chatting with a colleague and friend, who is well known in the world of equine internal medicine, we were discussing butyrate and impact on metabolism in general.  Butyrate is a short chain fatty acid produced within the digestive tract, generally as a result of a balanced microbiome.  This is just one of three important short chain fatty acids produced, but appears to be one of the more important, as far as human and rodent research is concerned.  In discussing butyrate, I mentioned to him that this coincided with my work and concerns regarding the digestive microbiome in the metabolic horse, noting how our research indicated an imbalance on fecal studies.  Considering there is often an imbalance present in the digestive microbiome in the EMS horse, it makes sense that likely butyrate levels would be low and that there could be a negative impact on metabolism.

My colleague agreed that likely a dysbiosis of the digestive tract in the horse strongly contributed to EMS, but he commented that it may be worthwhile taking a short cut, if you will, and supplement ketones (beta-hydroxybutyrate) or use MCT oils, to help boost the process along.  Beta-hydroxybutyrate is a ketone produced by the body as a result of the ketosis process, and is used in many energy and other pathways on a cellular level.  What my colleague was getting at was that in his exploration of metabolic syndrome, the generation of ketone bodies appears to be beneficial in human medicine on various levels, and thus he wondered what the impact was for the horse.  So, it is to him that I have to thank for pushing me in this area of exploration.

There is not a ton of research done in the horse regarding ketone production nor impact on metabolic conditions.  There is more data in human and rodent research.  We do know that the horse is capable of producing ketones, but the direct impact on metabolism and insulin function is unknown.  In one article, it is noted that with MCT oil administration in the horse, there is a reduction in insulin, but that is not much to work with. (Hallebeek, 2001) So, when I see this data on the human side, and the positive findings, I tend to explore it.  The reason that I do this is not to sell a product, but to do what I was trained to do, as a doctor, and that is to find solutions.

Let’s be honest, equine metabolic syndrome is becoming an epidemic of sorts and current therapy options are not working, at least for most.  While I am 100% behind the well-known insulin resistance horse group and their recommendations, the fact is that this approach is not working for a high percentage of those participants.  That is not saying the approach is not worthwhile, but that there is likely another problem.  I am all behind nutrition and exercise, and in the world of human metabolic problems, these two factors can actually solve the problem and cure the patient, if applied properly.

Is the reason for failure in the horse a result of improperly applying the nutrition and exercise recommendations?  For some, yes, to be honest.  For others, I personally believe that the cellular damage is much more extensive than what we’d like to believe.  In those cases, the owners may apply the recommendations and not get a response in the first 1-6 months, or maybe the response is not optimal in their eyes.  So, they quit, they abandon ship and the problems worsen.  It is possible if they just kept up the effort for another 6 months that the cells would respond and the horse would have gotten better.  Maybe the cellular damage was significant enough to require a longer period of time on the new diet and exercise.  We will never know in some of those cases.

On my end, most of the cases that I consult with or personally see have been down the diet road and exercise, while many have not.  Proper diet and exercise is always my first recommendation and with that recommendation, there is one or two supplements that I have always used to support that horse.  Most respond well, if the owner is on board and makes the appropriate changes.  Others fail to respond either because the approach was not applied properly or consistently, or there is something else going on in the horse, on a cellular level.

Now, back to the issue at hand.

In the most recent press release put out, there were a few concerns noted.

It was mentioned that ketones and their generation are not important in the horse and research was noted to document this fact.  While there was this research, there are a few points to keep in mind.  The main issue with the project that was noted is that the horses evaluated were conditioned equine athletes, endurance athletes.  To me this is noteworthy, as there is likely a big difference in metabolism between a conditioned equine athlete and an equine metabolic syndrome patient.  It was noted in the study that there was a small but significant rise in ketone generation in those horses, but it was deemed unimportant.  Okay, point taken, but let’s keep in mind the group we are looking at and assessing.

When I was given the challenge to explore ketone generation in the horse, I took it on and evaluated many different breeds, genders, and levels of conditioning.  Although my data is not published, nor never will be, what I can say is that there are some horses that are capable of producing ketones post meal or post-fasting, while there are some that cannot.  A state of ketosis is defined as being greater than a level of  0.5 mmol.  On the human side, using the ketogenic diet, most individuals seeking clinical results strive for a state of nutritional ketosis in the range of 1.0-1.5 mmol.  Is this a level we should seek in the horse??  Good question.

When comparing my data, it is noted that many more overweight horses generate ketones both post-prandial and post-fasting around 0.5-o.7 mmol, with some actually registering on the device as ‘too low to measure’.  In this group fell several horses that were indeed diagnosed as metabolic syndrome patients, with insulin levels well above normal,  being > 40 uIU/ml.  Now, compare that to fit OTTB’s that are not metabolic with insulin levels in the range of 12-25 uIU/ml.  Those horses generated ketones both post-prandial and fasting around 0.9-1.2 mmol.  This was with no intervention other than a good, whole-food diet.

So, if ketones are not important, then why is there a difference between the two groups of horses, at least in my clinical research??  Why did the conditioned OTTB’s generate higher ketone levels post-prandial and after a night’s fasting?

Through my eyes, I see a problem.  Research may tell us that ketone generation is not important in the horse, but what horse are we referring to??  Is it safe to say that just because ketone utilization is not important for a fit and conditioned endurance horse that it is likewise not important for a metabolic syndrome equine patient?  Isn’t this like comparing a fasting blood sugar of an overweight person to a fasting blood sugar of a conditioned human athlete? The two may be the same species, but one is conditioned, and with that conditioning, there is likely a more efficient state of metabolism. 

To go one step further, trying to unravel the big picture, I tend to dig deeper and look at cellular function on the only level I can, which is through evaluation of internal antioxidant defenses and free radical generation in the body, through a given blood sample.  The normal values for the horse have been determined, using the device I have in my facility, based on research out of Europe.  This information can be made available for those that are seeking.

In evaluating several EMS horses, both in my facility and from areas outside of my area, it is noted that a high percentage of these EMS horses have both a deficiency in internal antioxidant reserves and also a lower than normal free radical level.  This does not apply to all EMS horses, but many that I tested.  In comparison, the fit OTTB horse in our facility generally had a normal range for both free radicals and internal antioxidant reserves.  So, again, we have to raise a finger and point out there may be a problem.

What this tells me, and researchers that I communicated with in the field of oxidative stress, is that likely there is a cellular hyporeactivity response, meaning, the cells are not functioning correctly at a mitochondrial level.  The body requires and desires a certain level of both free radicals and antioxidants in order to maintain balance.  We do not wish for lower than normal levels in either category, as this can then equate to a state of ill-health, at least on a cellular level.  This lack of cellular response, lack of cellular health, could be a sign of improper energy utilization or a reflection there of.  In the EMS horse, we do have insulin dysfunction, which then implies improper glucose utilization.  Considering this, it is very plausible that the EMS horse is simply not functioning well at a cellular level due to this improper glucose utilization, leading to an energy deficit by nature.

Now, let’s fast forward.

In seeing this preliminary data and being the person that I am, I have to explore options.  I don’t dismiss things easily.  So, the next step was to approach the ketosis situation in the horse, but seeing the nature of the horse and their diet, a true ketogenic diet is not possible nor desirable.  Considering that many of the horses that I evaluated were already on recommendations made by the insulin resistant horse group, yet still showing low ketone levels compared to the normal OTTB, I decided to do what is done on the human side and that was to try to encourage the horse’s body to generate those ketones.   This is when we started to experiment with both exogenous ketone administration and MCT oil usage in the horse.

What did we find in our studies?

In the average pre-metabolic and metabolic horse, the use of either exogenous ketones (BHB) or MCT oils raised their post-prandial ketone levels by an average of 0.5 mmol, raising their levels up to an average of 1.1 mmol.  In addition, the horses that were on either the exogenous ketones or MCT oils also tended to have the lowest post-prandial glucose levels, with an average of 69-72 mg/ml, compared to others that tended to be in the range of 80-94 mg/ml.  Some of these horses were dosed in the mornings, and then tested 8-10 hours later after consuming pasture, and still demonstrated higher ketone and lower blood glucose levels compared to the control groups.  Some of these horses demonstrated glucose levels in the range of 69-72 mg/dl after 8 hours of consuming pasture with ketone levels in the range of 0.7 mmol, compared to non-supplement horses with glucose levels as high as 96 mg/dl and ketone levels registering as ‘low’ or non-detectable.

In some horses, insulin levels were re-evaluated after 14 days of therapy, depending on funds available to cover testing, and it was noted that most had a reduced insulin level by 10-15% or more.  Even in the conditioned OTTB, it was interesting to note that a normal insulin level of 20 uIU was reduced to a level of 12 uIU/ml after 14 days of therapy.

Upon re-evaluation of free radical and antioxidant levels, many of the horses improved, but still remained on the ‘low’ levels in both categories.  Clinically, though, the horses seemed to be improved. This improvement, albeit small, may be attributed to an altered cellular pathway for cellular energy production, through the ketones generated or provided to the body exogenously.

In speaking with a well known researcher in the world of oxidative stress and mitochondrial damage, the potential solution was offered to consider specific antioxidants, which may help to protect the cells, build antioxidant reserves, and improve cellular function.  These were specific antioxidant compounds that would not likely pose a problem in regards to antioxidant recharging.  There are a few of these antioxidants, which include astanxanthin, melatonin, acetyl-carnitine, and alpha lipoic acid.

These recommendations were pursued on my end, in a small group of patients, and the antioxidant blend was administered once daily.  After 7 days of administration, blood levels were re-evaluated and it was noted that both free radical and antioxidant reserves had increased back towards baseline normal.

What’s the bottom line?

I’m not trying to defend our research or articles.  I have no reason to do this as I know what I have seen in our clinical patients.  I am not in a research lab, away from equine patients, but am actively seeing, consulting with and applying therapies in horses almost every day.  I take theories, plausible theories, and explore them and let the answers unfold.

Are ketones important to the average horse?  Not likely, but then again, to the average human, they are not generated on a very high level either.  However, in a state of disease, the conditions change and likely the ketones do play a much greater role.  One may say ketones do not play a role in equine metabolic syndrome, which this may or may not be true.  However, this was noted in the condition of Alzheimer’s as well, several years ago, and only recently are they now noting that this cognitive condition is actually a reflection of insulin resistance at the level of the brain, noting moderate responses to both exogenous ketones and MCT oils.  In the case of Alzheimer’s, ketones usage and generation is not a cure, but appears to offer cells a new source of energy, which can prove useful for re-establishing a state of health. This is what I am implying with ketone usage and generation in the horse.

Do ketones and MCT oils play a role in equine metabolic syndrome?  To me, the answer is ‘yes’, but how deeply is unknown.  They are not a cure, but may provide an alternate pathway for jump starting cellular function in the horse.  I know there are many out there that want hard data and in response to that, I would say, provide the funding and I will get you the data.  Otherwise, I have to go with clinical research and experience.

Lastly, I think there were some criticisms posed by the insulin support group for horses regarding the dosage that I utilize and associated cost.

The dose was arrived at not based on human data or doses, but more by trial and error.  The dose of MCT oils that we arrived at was the dose that raised most horses’ ketone levels up to a level of 1.0-1.5 mmol, which is the nutritional ketosis state desired in human medicine.  It is very possible that a lower dose could also be effective, but we did not explore.  This lower than human dose, in comparison, may be reflective of the ease in which the equine body is capable of generating ketone bodies given the correct substrate.  Every horse is different, as every dog is different and every person.  Just because we prescribe insulin to a person or a dog for type I diabetes does not mean every one will have the same dose.  One dog may respond to 2 units, while another requires 30 units.  We should think no different regarding exogenous ketones or MCT oils.

Second, regarding cost, let’s look at some human supplement comparisons.

Human MCT oil supplements average around $25 for 30 ounces.  The MCT oil supplement that we utilized averages $134 for 128 ounces.  Considering the different blends offered, we are not far off course from human pricing.

Human exogenous ketone supplements, a 240 gram product runs on average $20, while the exogenous BHB-Mg that we utilize provides 630 grams for a price of $77.  So, again, pricing is very close to what is offered on the human side.

I think the biggest issue that we forget is that we are supplementing a horse, 500 kg, and not a human at 75 kg.

I don’t have all of the answers, trust me, but my goal here is to let you know what I have seen and witnessed clinically.  If we dismiss something, then it is very possible we could be missing a major piece to the puzzle.  I am not implying that ketones are the sole answer, but am more so implying that some of these EMS horses may be more clinically compromised than we’d like to believe.  In seeing this, the use of ketones, either exogenously or generating them through the use of MCT oils may provide clinical benefits to that patient.

I’m not here to start an argument with anyone or any of my colleagues.  As mentioned, I respect the insulin support group for horses and implement their strategies with many of my patients, as we do agree on a few things.  However, many horses simply do not respond clinically.  While this is often the fault of the owner in applying those measures, in other instances, it is not.  It is my responsibility as a veterinarian to seek options for those horses, and this is what I am simply doing.

As a summation, I will state that the use of exogenous ketones and MCT oils do pose possibilities in the equine metabolic syndrome patient.  While there is research to the contrary, I do not feel this research applies to the deranged state of metabolism which the EMS patient is demonstrating.  I do not feel that these therapies are cures for the condition of EMS or insulin resistance, but more so may pose as a tool or instrument which can be used to better improve the state of well-being and cellular health in the horse.

One thing to keep in mind is that just as with insulin, these therapies should not be arbitrarily utilized in any EMS horse.  A proper diet, lifestyle, exercise and foot care are paramount and should be addressed first and foremost.  If exogenous ketones or MCT oils are utilized, I feel that best results are obtained when the horse is monitored for blood glucose, ketone levels, and periodic evaluations of insulin.  The blood glucose and ketone levels can be monitored by any owner willing to purchase the hand held devices and draw blood as needed.  In addition, I do feel it is helpful to assess for cellular function, which in our laboratory is through free radical and antioxidant reserve testing.  This further testing allows us to see deeper into the horse and evaluate their current ketone generation status, glucose levels, and cellular function.  Having this information at hand can then better guide us, as veterinarians, regarding therapy options.


Author:  Tom Schell, D.V.M., CVCH, CHN



Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.