Understanding Type 2 Diabetes in Horses: Insulin Dysregulation Explained

Horse owners sometimes ask whether horses can develop “type 2 diabetes.” While true, overt diabetes mellitus is rare in horses, they commonly develop a related condition called insulin dysregulation, often as part of Equine Metabolic Syndrome (EMS) (Durham et al., 2019).

Insulin dysregulation includes insulin resistance, excessive insulin responses to meals, and sometimes persistent hyperinsulinemia. Although the terminology differs from human medicine, the underlying issues—obesity-driven insulin resistance, pancreatic strain, and impaired glucose handling—are strikingly similar to type 2 diabetes in people.

When True Diabetes Does Occur

In rare cases, horses can develop persistent hyperglycemia and beta-cell exhaustion consistent with diabetes mellitus, particularly in older or chronically stressed individuals (Schott, 2002). However, most at-risk horses present earlier with insulin dysregulation and laminitis risk rather than full-blown diabetes.

Common Signs of Insulin Dysregulation

Frank et al. (2010) describe typical features such as:

• Regional fat deposits (cresty neck, fat pads over ribs and tailhead)
• Easy weight gain despite modest feeding
• Recurrent or unexplained laminitis

Management: Think Forage-First and Low-NSC

Dietary management is the cornerstone of care:

• Prioritize low-NSC, forage-based diets
• Soak hay when appropriate to reduce water-soluble carbohydrates
• Eliminate grains and high-sugar feeds
• Introduce consistent, low-impact exercise when laminitis is not active

Though horses don’t commonly develop type 2 diabetes in the exact way humans do, the parallels in insulin dysregulation and laminitis risk demand the same level of vigilance and early intervention from owners and veterinary teams.

References

Durham, A. E., et al. (2019). “Management of equine endocrine disorders.” Equine Veterinary Education.
Schott, H. C. (2002). “Diabetes mellitus in horses: A rare but serious condition.” Equine Veterinary Journal.
Frank, N., et al. (2010). “Equine metabolic syndrome.” Journal of Veterinary Internal Medicine.