The Real Issue with Sugar and Molasses for Horses: A Science-Backed Look at Sweetness in the Equine Diet

Sugar in horse diets has been a hot topic for decades. Like many areas of equine nutrition, the science can be nuanced — even conflicting. One study may suggest certain hay varieties are completely safe, while another warns that high sugar content can be detrimental, especially for metabolically challenged horses. So what’s the real deal? The short answer: it all comes down to your horse’s individual health status and how much sugar they’re really consuming.

In this article, we’ll break down what sugar does to horses, where it hides in their diets, and how to make informed, science-backed feeding decisions to support equine wellness.

Why Sugar Isn’t the Enemy (Until It Is)

Let’s set the record straight: sugar is not inherently harmful. Glucose, a simple sugar, is the body’s primary source of fuel — not just for humans, but also for horses. It's essential for muscle contractions, brain function, and even cellular repair. Horses have evolved to eat forage, which naturally contains non-structural carbohydrates (NSCs), including simple sugars, starches, and fructans. Under normal circumstances, their digestive system is well-equipped to process these in moderate amounts.

However, trouble arises when horses consume excessive amounts of sugar or when they suffer from metabolic conditions that impair their ability to manage blood sugar and insulin levels effectively.

The Role of Molasses: Tasty but Tricky

Molasses, a byproduct of sugar production, is commonly used in horse feeds to enhance palatability and reduce dust. It typically contains about 50% sugar and is often included in pelleted feeds, sweet feeds, and even some supplements.

While molasses is generally safe for healthy horses, it poses a real risk to horses with:

• Equine Metabolic Syndrome (EMS)

• Insulin Dysregulation (ID)

• Cushing’s Disease/PPID

• A history or predisposition to laminitis

  
  

In these horses, even small amounts of added sugar can tip the scales toward metabolic instability or trigger a painful laminitic episode.

How Sugar Affects Metabolic Health

Research published in the Journal of Veterinary Internal Medicine (Frank et al., 2010) found that horses with EMS experience an exaggerated insulin response when consuming diets high in NSCs. This means that even a relatively normal amount of sugar or starch can cause prolonged elevations in insulin levels, which has been directly linked to the onset of laminitis.

Chronic insulin dysregulation results in:

• Impaired glucose uptake in muscle tissue

• Increased fat deposition (especially in the crest of the neck and rump)

• Hormonal imbalances

• Reduced immune function

  
  

Long-term, this creates a metabolic "perfect storm" that can severely affect your horse’s quality of life and longevity.

Sugar, Gut Health, and Colic

Another concern is the impact of high sugar intake on gut microbiota. Excessive sugars and starches can lead to microbial imbalances in the hindgut — a condition called hindgut acidosis. When large quantities of undigested sugars enter the cecum and colon, they ferment rapidly, producing lactic acid. This drop in pH can kill off beneficial bacteria and promote the growth of pathogenic species, increasing the risk of:

• Colic

• Diarrhea

• Poor nutrient absorption

• Behavior changes linked to gut discomfort

  
  

According to research from the University of Kentucky, high-starch diets are strongly associated with digestive upset in horses, particularly when fed in large, infrequent meals rather than small, regular feedings.

Where Sugar Hides in the Equine Diet

Sugar isn’t always in the most obvious places. Aside from molasses-laced sweet feeds, sugar can be lurking in:

• Commercial pellets labeled “complete” or “performance”

• Supplements, especially those with flavorings

• Horse treats, even those marketed as “natural”

• Hay and pasture, particularly in early spring and late fall

  
  

Even forage — the backbone of the equine diet — can be surprisingly high in NSCs. Certain grasses like ryegrass, early-cut orchardgrass, and fescue can test over 20% NSCs, a dangerous level for sugar-sensitive horses.

The Truth About Hay and Sugars

While hay is often considered a "safe" food, its sugar content can vary wildly. Factors that influence NSC levels in hay include:

• Grass species

• Stage of maturity at cutting

• Time of day harvested (afternoon = higher sugars)

• Environmental conditions (drought, frost, etc.)

• Storage methods

  
  

The only way to know your hay’s sugar content is through forage testing. Labs like Dairy One and Equi-Analytical offer comprehensive hay analysis services. For sugar-sensitive horses, aim for hay under 10% NSC. Good options include:

• Teff hay (5–10% NSC)

• Timothy hay (often <12% if mature and late-cut)

• Mature Bermuda grass hay

  
  

Soaking hay in cold water for 30–60 minutes can reduce NSC content by up to 30%, though this also leaches important minerals and should be done strategically.

Smarter Feeding Strategies

If you're looking to reduce sugar in your horse’s diet, try these evidence-based swaps:

Instead of...	Try This...
Sweet feed	Low-NSC ration balancer
Molasses-rich beet pulp	Beet pulp without molasses
High-starch grains	Soaked hay cubes, hay pellets
Processed treats	Homemade or low-sugar commercial options
Calorie boosters like corn or oats	Healthy omega-3 supplements

Fats and oils provide calorie-dense energy without the insulin-spiking effects of sugar. Studies from Colorado State University have shown that adding fat to the diet does not elevate insulin levels and is a safe energy source for horses with metabolic issues.

Responsible Treating

Treats are part of the joy of horse ownership. However, it’s wise to limit sugary options like apples, molasses-based cookies, and commercial “bites” that often contain corn syrup or wheat middlings. Instead, look for:

• Dehydrated vegetables (like beet or celery pieces)

• Low-NSC horse cookies

• Treats made with chia, flax, or alfalfa as the base

  
  

Products like Twenty Four Carrots Super Food Horse Treats are third-party tested and formulated specifically for sugar-sensitive horses — a smart way to spoil your horse safely.

Final Thoughts On Molasses For Horses: Nutrition Is Preventative Medicine

Sugar and molasses aren't evil — but they do need to be respected, especially in horses with metabolic sensitivities. Excess sugar can disrupt the microbiome, trigger inflammatory responses, and lead to chronic conditions that are difficult (and expensive) to manage.

Luckily, modern science has armed horse owners with the tools to prevent these issues before they begin. Regular forage testing, label-reading vigilance, and thoughtful feed selection can go a long way in protecting your horse’s health and performance.

Because at the end of the day, your horse deserves to feel their best. And that starts with what’s in the feed bucket.

References:

• Frank, N. et al. (2010). Equine Metabolic Syndrome. Journal of Veterinary Internal Medicine, 24(3), 467-475.

• Pagan, J. D. et al. (2006). The effect of starch intake on the incidence of colic and laminitis in horses. Kentucky Equine Research.

• Longland, A. C., & Byrd, B. M. (2006). Pasture nonstructural carbohydrates and equine laminitis. Journal of Nutrition, 136(7), 2099S–2102S.

• Harlow, B. E. et al. (2015). Influence of soaked hay on nutrient intake, behavior, and digestibility in horses. Journal of Animal Science, 93(1), 399–406.