What Is the Best Diet for a Horse With EMS? A Complete Feeding Guide
- Dr Silver
- Aug 9
- 16 min read
If your horse has Equine Metabolic Syndrome (EMS), one of the most important questions is:
What is the best diet for a horse with EMS?
The answer is more complicated than simply choosing a “low-sugar” feed.
EMS is closely associated with insulin dysregulation, and insulin dysregulation is a major risk factor for endocrinopathic laminitis. Dietary management is therefore a central part of managing an affected horse, but the right diet needs to be based on the individual horse rather than a single percentage printed on a feed or hay analysis.
For some horses, reducing excess calories and body fat is a major priority. For others, particularly lean horses with insulin dysregulation, carbohydrate control may be more important than further calorie restriction.
And importantly, there is no single sugar or starch level that can be guaranteed to be safe for every horse.
A forage that appears “low sugar” on paper may still produce a significant insulin response in a particularly insulin-dysregulated horse, depending on how much is consumed and how the individual horse responds.
This guide explains the science behind feeding horses with EMS, including forage, NSC, sugar and starch, grazing, weight management, exercise and the role of nutritional supplementation.
Important: This article is educational information, not a diagnosis or veterinary treatment plan. EMS and insulin dysregulation should be assessed with appropriate veterinary input. If your horse is showing signs of laminitis or acute lameness, contact your veterinary surgeon promptly.
What Is Equine Metabolic Syndrome?
Equine Metabolic Syndrome is a metabolic disorder in which insulin dysregulation is a central feature, often accompanied by obesity or abnormal regional fat deposition and an increased risk of endocrinopathic laminitis.
However, EMS is not simply a condition of being overweight.
Some horses with insulin dysregulation may be overweight, while others can have insulin dysregulation despite appearing relatively lean.
This is why body condition alone cannot diagnose EMS.
Veterinary assessment may include the horse's history, body condition, clinical findings and appropriate laboratory testing.
The ECEIM consensus statement identifies insulin dysregulation as the most important risk factor for endocrinopathic laminitis and states that EMS management is based mainly on dietary strategies and exercise, with the aim of improving insulin regulation and reducing obesity where it is present.
What Is the Best Diet for a Horse With EMS?
There is no single “EMS diet” that is correct for every horse.
However, the most important principles are generally:
Control excessive calorie intake where weight loss is required.
Control dietary non-structural carbohydrates (NSC).
Use forage as the foundation of the ration.
Avoid unnecessary high-sugar or high-starch concentrate feeds.
Manage pasture access carefully.
Maintain nutritional adequacy while controlling calories and carbohydrates.
Introduce dietary changes gradually.
Use exercise where the horse is physically able to exercise safely.
Monitor body condition and, where appropriate, insulin dysregulation over time.
The most important point is that the diet should be designed around the individual horse.
An overweight horse with EMS may need significant calorie restriction.
A lean horse with insulin dysregulation may need carbohydrate control without further weight loss.
A horse with previous endocrinopathic laminitis may require more conservative management than a horse with metabolic risk but no history of laminitis.
Why Is Forage So Important?
Forage should normally remain the foundation of an equine diet.
Horses are adapted to consuming forage for much of the day, and fibre supports normal digestive function and natural feeding behaviour.
However, forage is not nutritionally identical.
Hay, haylage and pasture can vary substantially in:
Sugar
Starch
Water-soluble carbohydrates
Energy
Protein
Fibre
Mineral content
For a horse with insulin dysregulation, the carbohydrate and calorie content of forage therefore matters.
This is why forage analysis can be useful.
Rather than relying on whether hay looks mature, stemmy, green or soft, laboratory analysis can provide more objective information about its nutritional composition.
But there is an important limitation:
A forage analysis does not predict exactly how an individual insulin-dysregulated horse will respond to that forage.
Is 10–12% NSC Always Safe for a Horse With EMS?
No.
This is one of the most important points to understand.
A commonly used recommendation is to select forage with relatively low NSC, often around 10–12% or below on a dry-matter basis.
The British Horse Society currently describes forage below 10–12% sugar and starch as generally safer for overweight horses, horses with EMS and horses prone to laminitis.
However, this should not be interpreted as:
“12% NSC is safe for every horse with EMS.”
It is not that simple.
Recent research has highlighted substantial variation in insulin responses between insulin-dysregulated horses and suggests that the amount of NSC consumed per meal relative to bodyweight may be highly relevant.
One 2025 study found that insulin-dysregulated horses had increased insulin responses when meal NSC intake reached approximately 0.11–0.12 g/kg bodyweight, with individual variation between horses.
Other recent research has also discussed a much lower target of approximately 0.1 g NSC/kg bodyweight per meal when the objective is to minimise insulin responses in insulin-dysregulated horses.
This means that NSC percentage and NSC dose are not the same thing.
Why NSC percentage alone can be misleading
Imagine two horses eating forage containing exactly the same 5% NSC.
Horse A eats a relatively small amount.
Horse B consumes a much larger amount.
The percentage of NSC in the forage has not changed, but the total amount of NSC consumed has.
This is why the horse's:
Bodyweight
Amount of forage consumed
NSC concentration
Meal size
Feeding frequency
Individual insulin response
all matter.
For some horses with significant insulin dysregulation, even apparently low-NSC forage may need to be carefully managed.
This is one reason why a simple statement such as “feed anything below 10%” can be misleading when presented without context.
Can a Horse With EMS React to Very Low-Sugar Forage?
Potentially, yes.
Individual insulin responses vary.
Research has demonstrated that insulin-dysregulated horses can respond differently to the same feed, and newer studies are investigating the relationship between forage NSC concentration, meal size and insulin response more closely.
A 2024 study involving insulin-dysregulated horses found considerable individual variation in metabolic responses even when horses were offered low-NSC forage pellets.
This does not mean that all low-NSC forage is dangerous.
Quite the opposite: lowering dietary NSC remains an important part of metabolic management.
It means that “low NSC” should be regarded as a management tool rather than a guarantee of a normal insulin response.
For a horse with marked insulin dysregulation or previous endocrinopathic laminitis, veterinary guidance is particularly important.
What Is NSC?
NSC stands for non-structural carbohydrates.
In practical equine nutrition, NSC is generally used to describe carbohydrates such as:
Sugars
Starch
Depending on the laboratory and calculation method, terminology and reporting can vary.
This is important when comparing forage analyses.
For example, one laboratory may report water-soluble carbohydrates separately, while another may provide a combined figure.
Always check exactly what the reported number represents.
Sugar and Starch Are Not the Whole Diet
It is tempting to focus entirely on sugar.
But metabolic management is broader than that.
A horse's overall metabolic response can be influenced by:
Total calorie intake
Body condition
NSC concentration
NSC intake per meal
Pasture exposure
Exercise
Insulin sensitivity
Individual metabolic status
Other dietary components
This is why a horse can remain metabolically challenged despite apparently eating a “low-sugar” diet if the overall calorie intake, pasture exposure or feeding strategy is inappropriate.
What Is the Best Hay for a Horse With EMS?
There is no single type of hay that is automatically best.
The ideal forage depends on the individual horse and its nutritional requirements.
Rather than choosing hay based only on its type or appearance, consider:
NSC concentration
Energy density
Fibre content
Protein
Mineral profile
Dry matter
Palatability
How much the horse needs to consume
Whether the horse needs to gain, maintain or lose weight
For an overweight horse with insulin dysregulation, a mature, lower-energy forage may be useful if its carbohydrate profile is appropriate.
For a lean horse with insulin dysregulation, however, simply choosing the lowest-calorie forage available may not be appropriate.
The goal is not to make every EMS horse thin.
The goal is to provide an appropriate and nutritionally complete diet while managing metabolic risk.
Should You Soak Hay for a Horse With EMS?
Soaking hay can reduce water-soluble carbohydrates in some forage.
However, the amount removed is not guaranteed.
It can depend on:
The original sugar content
The type of forage
Soaking time
Water temperature
Water volume
Environmental conditions
Soaking should therefore not be treated as a precise method for achieving a particular NSC percentage unless the resulting forage has been analysed.
The British Horse Society currently recommends soaking hay as one option for reducing sugar where appropriate and provides guidance on soaking times.
Soaking can also alter the mineral contribution of the forage.
For horses requiring tightly controlled nutrition, consider the entire ration rather than focusing only on the sugar removed by soaking.
How Much Forage Should an EMS Horse Eat?
This depends on the horse.
An overweight horse may need controlled forage intake to create an appropriate calorie deficit.
But restricting forage too aggressively can create other welfare and health problems.
Horses need sufficient fibre, and long periods without forage are undesirable.
A structured weight-loss programme should therefore consider:
Current bodyweight
Target bodyweight
Body condition score
Forage dry matter
Forage energy density
NSC concentration
Total daily intake
Feeding frequency
Exercise
Pasture intake
Forage should ideally be weighed rather than estimated by the size of a haynet.
Your veterinary surgeon or qualified equine nutritionist can help calculate an appropriate ration.
Why Does Weight Matter in EMS?
Obesity and abnormal fat deposition are strongly associated with insulin dysregulation and metabolic risk.
However, body condition is only part of the picture.
A horse can have insulin dysregulation without being obviously obese.
Conversely, not every overweight horse will necessarily have the same degree of insulin dysregulation.
This is why weight management should be combined with appropriate veterinary assessment where EMS is suspected.
Useful monitoring methods include:
Body condition scoring
Regular weight measurements
Weight tapes
Consistent photographs
Monitoring the neck crest
Monitoring regional fat deposits
Veterinary testing where appropriate
Look at the trend rather than one measurement.
Can an Overweight Horse With EMS Lose Weight Safely?
Yes.
For an overweight horse with EMS, gradual weight loss can be an important part of reducing metabolic risk.
The aim should be controlled weight loss rather than rapid starvation.
A weight-management programme may include:
Lower-energy forage
Appropriate NSC control
Measured forage intake
Restricted pasture
A suitable grazing muzzle where appropriate
Removal of unnecessary calorie-dense feeds
Appropriate exercise
Regular monitoring
If your horse has a history of laminitis, significant insulin dysregulation or current lameness, veterinary advice should be obtained before implementing a major weight-loss programme.
What If My EMS Horse Is Already Lean?
T
his is where generic EMS advice can become problematic.
A lean horse with insulin dysregulation does not necessarily need aggressive calorie restriction.
The priority may instead be to manage carbohydrate exposure while maintaining appropriate calorie, protein, vitamin and mineral intake.
Trying to make a lean horse thinner simply because it has insulin dysregulation is not the goal.
The correct question is:
How can we control metabolic risk while maintaining appropriate body condition and nutritional status?
This is why EMS management should be individualised.
What Hard Feed Is Best for a Horse With EMS?
Many horses with EMS do not require traditional high-energy conditioning feeds.
If additional feed is needed, consider a product that provides nutritional value without unnecessarily increasing calorie, sugar or starch intake.
A low-calorie vitamin and mineral balancer may be appropriate for some horses.
However, “low sugar” on the front of a bag does not automatically mean that a feed is appropriate.
Look at:
Sugar
Starch
NSC
Calories
Feeding rate
Protein
Vitamins and minerals
The rest of the ration
A feed containing a relatively low percentage of NSC can still provide a meaningful NSC dose if it is fed in a large meal.
This is another reason why feeding rate matters as well as percentage.
Should an EMS Horse Eat Grass?
Pasture can be one of the most challenging aspects of EMS management.
Grass carbohydrate concentration can vary with:
Season
Weather
Plant maturity
Time of day
Growing conditions
Grazing pressure
Species and pasture composition
Therefore, unrestricted pasture access may not be appropriate for every insulin-dysregulated horse.
Management options may include:
Restricted turnout
Track systems
Strip grazing
Grazing muzzles
Dry lots
Alternative turnout areas
Controlled forage provision
The appropriate strategy depends on the individual horse.
A grazing muzzle can reduce grass intake in suitable horses, but it must be correctly fitted and monitored.
Is Grass Always Bad for a Horse With EMS?
No.
Grass is not inherently “bad”.
The issue is the amount of carbohydrate and energy consumed and how the individual horse responds.
Some horses with EMS may tolerate carefully controlled pasture access.
Others, particularly horses with significant insulin dysregulation or a history of endocrinopathic laminitis, may require much stricter pasture management.
This is why simply saying “EMS horses must never eat grass” is also an oversimplification.
Can Exercise Help a Horse With EMS?
Exercise can be an important component of EMS management in horses that are physically able to exercise.
Appropriate exercise can help with:
Energy expenditure
Weight management
Fitness
Insulin sensitivity
However, exercise should never be prescribed blindly.
A horse with active laminitis, significant lameness or unexplained foot pain should not simply be exercised in an attempt to improve insulin sensitivity.
Veterinary assessment should come first.
For a sound horse, exercise should be introduced progressively and appropriate to its age, fitness, workload and other health considerations.
The ECEIM consensus statement identifies exercise alongside dietary management as a key part of EMS management.
Do EMS Horses Need Vitamins and Minerals?
Yes, an appropriate diet still needs to meet the horse's nutritional requirements.
Reducing calories does not mean that vitamins and minerals should be neglected.
This is particularly important when forage intake is restricted or when a horse receives little or no concentrate feed.
Depending on the forage analysis and the rest of the ration, a low-calorie vitamin and mineral balancer may be useful.
The exact requirements should be considered as part of the whole ration.
Adding multiple supplements without understanding the underlying diet does not automatically make the diet more balanced.
Do EMS Horses Need Supplements?
Not necessarily.
The foundation of EMS management is:
Diet + body condition + pasture management + appropriate exercise + veterinary monitoring where required.
A supplement cannot compensate for excessive calorie intake, uncontrolled grazing or inappropriate carbohydrate intake.
However, nutritional supplementation may have a place when it provides nutrients or ingredients that are appropriate for the individual horse and fit within the overall ration.
The evidence for individual supplements varies considerably, and not every ingredient marketed for “metabolic support” has strong clinical evidence in horses.
This distinction matters.
A supplement should be considered supportive nutrition, not a replacement for evidence-based EMS management.
What About Dr Silver EMS & Insulin Support PRO?
Dr Silver EMS & Insulin Support PRO is a complementary feed formulated for horses and ponies requiring nutritional support alongside a controlled, low-sugar diet.
The current formulation contains:
Magnesium oxide
Agnus castus
Triphala
Milk thistle
Spirulina
Mycorsob A+
White willow bark
Rosehip
Dr Silver's product information describes the formula as supporting normal insulin metabolism, gut function, liver function, antioxidant support and healthy metabolic and hoof function.
The current feeding guide is:
Horses: 30 g daily
Ponies: 20 g daily
It is designed to be fed alongside forage and a balanced, low-sugar diet.
It is important to be precise about what a product can and cannot do.
Dr Silver EMS & Insulin Support PRO is a complementary feed, not a veterinary medicine.
It is not intended to diagnose, treat, cure or prevent EMS, laminitis or other disease.
It should therefore be considered as part of a wider nutritional and management programme rather than as a substitute for dietary control or veterinary care.
Can a Supplement Replace an EMS Diet?
No.
This is one of the most important points in this article.
A supplement cannot compensate for:
Excessive calorie intake
Uncontrolled grazing
High-NSC forage
Excessive concentrate feeding
Inappropriate weight management
The foundations of EMS management remain diet, weight management where appropriate, pasture control, exercise where safe and veterinary oversight.
Nutritional supplementation should sit alongside those fundamentals, not replace them.
What Should I Avoid Feeding a Horse With EMS?
There is no universal list of foods that every horse with EMS must never eat.
However, it is sensible to review sources of unnecessary sugar, starch and calories.
These can include:
High-starch cereal-based feeds
High-calorie conditioning feeds
Molasses-rich feeds
Large concentrate meals
Uncontrolled access to lush pasture
Excessive treats
Calorie-dense supplements
The important question is not simply:
“Is this feed low sugar?”
It is:
“How much sugar, starch, NSC and energy is this horse actually consuming each day and in each meal?”
That is a much more useful way to assess the diet.
What Treats Can You Give a Horse With EMS?
Treats count as part of the diet.
For a horse requiring strict calorie and carbohydrate control, treats may need to be limited.
Some owners choose small quantities of suitable low-calorie vegetables or use a portion of the horse's normal forage as a reward.
There is no universal treat that is appropriate for every metabolically sensitive horse.
If your horse has significant insulin dysregulation or previous laminitis, discuss treats with your veterinary surgeon or equine nutrition professional.
How Do You Manage EMS Long Term?
EMS management is a long-term process rather than a short-term “diet”.
The aim is to establish a routine that is practical, nutritionally appropriate and sustainable.
Long-term management may include:
Monitoring body condition regularly.
Analysing forage where appropriate.
Controlling NSC intake.
Controlling total calorie intake where weight loss is required.
Managing pasture access.
Providing appropriate vitamins and minerals.
Using suitable exercise when the horse is sound.
Monitoring for signs of laminitis.
Reviewing insulin dysregulation with your veterinary surgeon where appropriate.
Adjusting the diet as the horse's condition changes.
Metabolic status can change over time, so a feeding plan that was appropriate six months ago may not necessarily remain appropriate forever.
What Are the Warning Signs of Laminitis?
Because insulin dysregulation is associated with endocrinopathic laminitis, owners should know the warning signs.
Possible signs include:
Reluctance to move
Short or pottery steps
Difficulty turning
Increased digital pulses
Heat in the feet
Shifting weight between limbs
A changed stance
Lameness or altered gait
Increased hoof sensitivity
Laminitis can be a serious veterinary emergency.
If you suspect laminitis, contact your veterinary surgeon promptly.
Do not attempt to manage suspected acute laminitis with supplements alone.
When Should an EMS Horse See a Vet?
Veterinary involvement is particularly important when:
EMS is suspected but has not been diagnosed.
Your horse has previously suffered laminitis.
Your horse is currently lame.
Your horse shows signs that could indicate laminitis.
Your horse is significantly overweight.
Your horse is unexpectedly losing weight.
You are considering substantial dietary restriction.
Your horse is receiving medication.
You are unsure whether your horse is insulin dysregulated.
EMS diagnosis should not be based solely on a cresty neck, body condition or the horse's breed.
Veterinary assessment and appropriate testing can help establish whether insulin dysregulation is present and guide management.
A Practical EMS Feeding Checklist
Before changing your horse's diet, ask:
☐ Has EMS or insulin dysregulation been diagnosed?
☐ What is my horse's current body condition?
☐ Does my horse actually need to lose weight?
☐ What is the NSC content of my forage?
☐ How much forage is my horse consuming each day?
☐ What is the estimated NSC dose per meal?
☐ Is pasture contributing significant carbohydrate or calories?
☐ Does my horse need concentrate feed?
☐ Is the ration nutritionally complete?
☐ Are treats adding unnecessary calories or carbohydrate?
☐ Can my horse exercise safely?
☐ Should forage be analysed?
☐ Does my horse need veterinary insulin testing or monitoring?
☐ Am I monitoring body condition over time?
The Bottom Line: What Is the Best Diet for a Horse With EMS?
The best diet for a horse with EMS is not a particular brand of feed, a single supplement or one magic sugar percentage.
It is an individualised feeding and management programme designed around the horse's metabolic status, body condition, forage, pasture access, exercise and nutritional requirements.
For many horses with EMS, the priorities are:
Appropriate forage
Careful control of NSC intake
Appropriate calorie control where weight loss is needed
Careful pasture management
Nutritionally complete feeding
Appropriate exercise where the horse is sound
Regular monitoring
Veterinary guidance where required
A forage analysis is useful, but a number on a hay report should not be treated as a guarantee that a particular forage will produce a safe insulin response in every horse.
This is especially important because newer research is showing that the amount of NSC consumed per meal, the horse's bodyweight and the individual metabolic response all matter.
A horse with severe insulin dysregulation may require much more careful management than a horse with milder metabolic risk.
Equally, an already lean horse should not automatically be subjected to aggressive calorie restriction simply because it has insulin dysregulation.
The goal is not to feed the lowest possible amount of food.
The goal is to provide the lowest practical metabolic risk while maintaining adequate nutrition, fibre, body condition and welfare.
At Dr Silver, we believe nutritional support should form part of a wider, horse-first approach.
Dr Silver EMS & Insulin Support PRO is designed as complementary nutritional support to be fed alongside a controlled, low-sugar diet. It is not a replacement for appropriate forage management, calorie control, pasture management, exercise or veterinary care.
The horse comes first. Always.
Frequently Asked Questions
What Is the Best Diet for a Horse With EMS?
The best diet depends on the individual horse. Management commonly focuses on appropriate forage, controlled NSC intake, calorie control where weight loss is required, pasture management and appropriate exercise.
What Is the Safest NSC Level for a Horse With EMS?
There is no single NSC percentage that is guaranteed to be safe for every insulin-dysregulated horse. Low-NSC forage is commonly recommended, but the amount consumed, meal size, bodyweight and individual insulin response also matter.
Can a Horse With EMS React to 5% NSC?
A very low NSC percentage does not guarantee that every horse will have the same insulin response. The amount consumed and the individual horse's metabolic response are important. Horses with significant insulin dysregulation may require particularly careful management under veterinary guidance.
What Hay Is Best for a Horse With EMS?
There is no single hay type that is best for every EMS horse. The nutritional composition of the actual forage is more useful than relying on its name or appearance. Forage analysis can help assess NSC and other nutritional characteristics.
Should I Soak Hay for a Horse With EMS?
Soaking can reduce water-soluble carbohydrates from hay, but the amount removed varies. If precise carbohydrate control is important, forage analysis can help determine the resulting nutritional profile.
Can a Horse With EMS Eat Grass?
Some horses with EMS may have carefully controlled pasture access, while others may require much stricter restriction. The appropriate strategy depends on the horse's metabolic status, body condition and laminitis history.
Is Grass Always Bad for Horses With EMS?
No. Grass is not inherently bad, but unrestricted pasture can provide substantial amounts of carbohydrate and calories. Individual pasture management is therefore important.
Can Exercise Help a Horse With EMS?
Appropriate exercise can support weight management and insulin sensitivity in horses that are physically able to exercise. Horses with active laminitis, lameness or foot pain should receive veterinary advice before exercise.
Do EMS Horses Need Supplements?
Not necessarily. Diet and management are the foundation of EMS management. A nutritional supplement may be appropriate where it fits the horse's overall ration, but it should not replace appropriate forage, calorie control, pasture management or veterinary care.
Can a Lean Horse Have EMS?
Yes. Insulin dysregulation can occur in horses that are not obviously overweight. Body condition alone cannot confirm or exclude insulin dysregulation.
Can a Horse Recover From EMS?
The metabolic abnormalities and risk factors associated with EMS can often be improved with appropriate management. However, metabolic risk can persist or return, so long-term monitoring and management are important.
What Should I Do If My EMS Horse Shows Signs of Laminitis?
Contact your veterinary surgeon promptly. Suspected laminitis requires appropriate veterinary assessment and should not be managed with a supplement alone.
Scientific References and Further Reading
Durham AE, Frank N, McGowan CM, Menzies-Gow NJ, Roelfsema I, Vervuert I, Feige K, Fey K. (2019). ECEIM consensus statement on equine metabolic syndrome. Journal of Veterinary Internal Medicine, 33(2), 335–349. DOI: 10.1111/jvim.15423.
Loos CMM, Urschel KL. (2025). Current understanding of insulin dysregulation and its relationship with carbohydrate and protein metabolism in horses. Domestic Animal Endocrinology. DOI: 10.1016/j.domaniend.2025.106940.
Macon EL, Harris P, McClendon M, Perron B, Adams AA. (2024). Insulin dysregulated horses metabolic responses to forage pellets. Journal of Equine Veterinary Science, 133, 104991. DOI: 10.1016/j.jevs.2023.104991.
Kerley BS, Harris P, Jacquay E, Askins M, McClendon M, Adams AA. (2025). Identifying insulinemic responses of ID horses offered varying levels of NSC and meal-sizes. Journal of Equine Veterinary Science, 151, 105638. DOI: 10.1016/j.jevs.2025.105638.
British Horse Society. Feeding Horses. Reviewed April 2026.
British Horse Society. Equine Metabolic Syndrome. Reviewed April 2026.
British Horse Society. Laminitis in Horses. Reviewed 2026.
About Dr Silver
Dr Silver is a UK-based equine supplement brand focused on functional nutritional support for horses and ponies.
Our approach considers the interconnected nature of equine digestive, metabolic, immune and musculoskeletal systems.
For horses requiring metabolic nutritional support, Dr Silver EMS & Insulin Support PRO is formulated to complement a controlled, low-sugar diet and wider management programme.
We believe good supplementation starts with good nutrition.
The horse comes first. Always.
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