Equine metabolic syndrome and insulin resistance have been a common problem but seem to be potentialy increasing in frequency or incidence over the past decade. As the number of cases of EMS or insulin resistance increases, we are ultimately left with determining the best means of controlling these horses for the long term. There have been proposed many theories of management, but not every approach works in every patient, often leaving us much to be desired.
EMS and insulin resistance often go hand in hand, but are not always present together. In many horses, it is a progressive stage of development, starting with signs of metabolic syndrome, then progressing to insulin resistance. The classic EMS or insulin resistant horse is perceived as an ‘easy keeper’, generally overweight with fat pockets over the hips, neck, sides and a deep valley or depression due to fat accumulation along the back. In addition to obvious clinical signs of being overweight, often these horses suffer from poor stamina, behavioral problems, lameness issues, low thyroid levels and even laminitis.
Contributors to EMS and IR include:
- Genetic predisposition (breed)
- Diet high in excess carbs and fats
- Decreased levels of exercise
- Increased stress levels
- Cushing’s Disease
Impact of EMS and IR on the horse include:
- Poor performance and stamina
- Increased lameness and prevalence of soft tissue injury
- Decreased immune function
- Low thyroid
Some more recent research has indicated that those horses with EMS are actually more prone over time to develop insulin resistance and even progress to Cushing’s disease. What is the connection? Likely, it is poor cellular function, oxidative stress and overall health deterioration.
How do we determine if our horse is impacted by metabolic syndrome and insulin resistance? True determination often comes with laboratory testing, which includes insulin and glucose level determination. This can be accomplished with a fasting blood sample but can also be determined through a glucose challenge test. In many instances, laboratory testing is inconclusive leaving us debating the status of our horse or patient. We have to also remember that insulin itself, is often viewed as an acute phase protein, which means that in time of injury or ongoing inflammation, the levels can rise, which doesn’t necessarily mean we have an insulin resistant patient for the long term.
In many cases, metabolic syndrome is hard to diagnose based on blood work, but more so we rely on clinical findings which include an overweight horse with fat pockets. This accumulation of excess fat can contribute not only to obesity, but also to the development of inflammation, cellular changes and activation of negative cellular pathways. As the condition progresses and more cellular damage occurs, then often we move from a state of metabolic syndrome to insulin resistance, in which cellular receptor and even DNA changes have occured.
So, how do we best manage these patients?
Traditional approaches include increase in exercise, reduction of sugars and fats from the diet. Many horses are placed on dry lots, fed lower quality hays, no grains or placed on low starch feeds. The ultimate question comes as to if this is the best approach? Are we just starving the body of the fuels needed to propel the condition or are we actually making changes for the better? It is in my opinion that this approach is more or less just stifling the problem more so than remedying it. In many of these cases, the horse may be controlled to an extent in regards to clinical signs but the patient continues to deteriorate in regards to hoof health, hair condition and even mentation. Insulin values may improve when retested, but at what cost to the horse? I have often wondered if in fact, in some cases, we are actually depriving many of these patients of vital nutrition needed for cellular repair and overall tissue health.
When research is evaluated, we come to understand that overweight or obese individuals, and animals, are more predisposed to a higher level of internal inflammation and oxidative stress. This is a result of negative pathways that are triggered post high fat meals in addition to a lower level of antioxidant intake as a result of a poor diet. When we have a higher state of inflammation and oxidative stress, then often the condition becomes progressive leading to the development of further health problems. Stress and subsequent increase in cortisol levels are also tied in with weight gain, poor sugar metabolism, insulin dysregulation and tissue degneration. So, again, we have to evaluate what is truly the best approach to these patients.
The increased chronic inflammatory state is evident in metabolic horses as compared to normal horses. In one study, metabolic and normal horses were exposed to an inflammatory trigger (LPS), which resulted in a more profound inflammation response in the metabolic patients as compared to the normal horses. This implies in theory that metabolic horses are actually a smoldering fire, waiting for a trigger to be applied, which then quickly results in disease manifestation or clinical worsening. This is evident in some cases when metabolic horses develop clinical signs of laminitis within a few days post vaccination.
Alternative approaches to EMS and insulin resistance take into consideration the cellular pathways that are activated, including the presence of unregulated inflammation which is contributing to cellular changes. Instead of just ‘starving’ the body of excess sugars, fats and potentially valuable nutrients, what happens if we try to modify those negative pathways?
Human research data has indicated that the increased consumption of flavonoids in the diet can impact glucose metabolism, impact insulin production and sensitivity, modify levels of inflammation in addition to providing antioxidant protection. Flavonoids are abundantly rich in many fruits and vegetables including blueberry, bilberry, noni fruit, green tea, parsley, pomegranate, tomatoes and even some legumes. It was originally thought that flavonoids impacted their benefits through antioxidant capabilities, but is now discovered that they can impact cellular signaling pathways which can have far reaching effects. Other herbs that have proven efficacy at down regulating pro-inflammatory pathways and improving insulin sensitivity including Curcumin, Boswellia and Ashwaghanda amongst many others. Dandelion root extract has demonstrated the ability to improve lipid levels and fat metabolism through regulation of gene translation and pancreatic lipase inhibition. Dandelion has also been shown to be a good source of Inulin, which acts as a pre-biotic and beneficial to the development and support of Bifidobacteria within the gut, which are known for regulating cholesterol and mineral absoprtion.
One of the main formulas that we have found beneficial in our equine patients is our Cur-OST® EQ Total Support, which combines many herbs including Curcumin and Dandelion to promote a healthy inflammation response, especially at a ‘gut’ level, in addition to providing many nutritive herbs and antioxidants. For added support, we will add in our Cur-OST® EQ Meta-Support® formula to provide various fruit flavonoids to aid in cellular health, a healthy insulin response and even support a healthy bodyweight.
Increasing exercise in metabolic patients is also a vital part of recovery. This is not always possible in laminitic patients, due to pain and discomfort, but any increase in exercise can be beneficial for calorie burning and weight loss. In many research papers, exercise has also been shown to improve insulin sensitivity.
What happens when we take this ‘alternative’ approach? In our clinical experience, the results can be very positive, helping to make the management of these patients much easier, often with very little changes to the diet. Instead of depriving the body of the fuel that accelerates degeneration, we are actually supporting overall health and impacting cellular pathways. In theory, if we control or manage those negative cellular pathways, then consumption of sugars and even fats may not play as big of a role in management. In research studies, when candidates were fed high fat meals concurrently with high flavonoid levels, dandelion, and curcumin, blood lipid levels were actually improved compared to controls, likely due to improved cellular function, inflammation modulation and antioxidant support, despite the high fat meal. In cases where high stress is a contributing factor, the supplemental use of Ashwaghanda (Cur-OST® EQ Adapt) has demonstrated benefit in controlling cortisol levels and subsequent negative health impacts.
What I have observed in clinical patients is that not only are secondary problems including laminitis more easily managed, but we experience weight loss, improved hair and hoof condition, patients feel better overall and in many instances insulin levels are reduced. I believe that many of the benefits are due not only to cellular pathway regulation, but also nutrient provision that actually enhances cellular health on many levels. I also believe that many of these patients have underlying ‘gut’ problems which may contribute not only to systemic inflammation, but may also impair nutrient absoprtion. If we can restore health and support a healthy inflammatory response, then often nutrients are more readily absorbed due to improved gut health.
Equine metabolic is a complicated syndrome, but becoming increasingly present in the industry. We have several approaches we can take in regards to managing these cases, but ideally, we need to look at a cellular level, realize what is occuring and how to best use dietary supplements to gain better control. If we take this approach, management of these conditions can be more complete and longer lasting with fewer flares, creating a more healthy patient in the end.
At Nouvelle Research, Inc., we are here to help!
All our best,
Tom Schell, D.V.M.
Nouvelle Research, Inc.