🔥 High-Starch Feeds Cause Inflammation in Horses: What to Know in 2025 🐴🥣

By Dr Duncan Houston BVSc

In 2025, the connection between nutrition and inflammation in horses is clearer than ever. New research confirms that high-starch diets can increase systemic inflammation, especially in overweight and older horses. This article explains what starch does in the equine body and why you should reconsider high-carb feed choices. 🧠🔥🐎

🧪 New Research on Starch and Inflammation

A study from Sam Houston State University found that diets high in starch increased levels of a potent inflammatory marker called interleukin-1 beta (IL-1β) in horses. Here’s what they discovered:

• 📊 Both overweight and senior horses had elevated IL-1β after eating high-starch meals
• ⚠️ Overweight horses showed this increase immediately
• 🧓 Even fit, middle-aged horses developed inflammation after 14 days of high starch intake

This confirms what veterinarians have long suspected: high-starch diets are pro-inflammatory and unsafe for certain horses. 🧬🔥

💥 Why IL-1β Matters: The Inflammation Cascade

Interleukin-1β is a cytokine that plays a major role in:

• 🔥 Triggering whole-body inflammation
• 🧠 Fueling neuroinflammation (linked to cognitive decline and Alzheimer's in humans)
• 🐴 Potentially contributing to colic, laminitis, insulin resistance, and Cushing’s

Horses experiencing chronic inflammation are more likely to have joint stiffness, metabolic dysregulation, and behavioral changes. 🚫

👴 Older Horses Are Especially at Risk

In the second phase of the study, two age groups were evaluated:

• 🟢 Younger horses (12–14 years)
• 🔴 Older horses (20–23 years)

Both groups received the same diet of steam-rolled barley, hay, and concentrate. After 36 days:

• 📈 Older horses had significantly higher inflammation markers

This suggests that age amplifies the inflammatory effect of starch—even when the diet is controlled. 📉🧠

🍞 What Are High-Starch Feeds?

Feeds that are high in non-structural carbohydrates (NSCs) typically include:

• 🌽 Corn, oats, barley
• 🍬 Sweet feed or molasses-based pellets
• 📦 Many traditional grain concentrates

Even if a feed is labeled as “senior” or “maintenance,” always check for starch and sugar content. Inflammation can occur even at moderate intake levels. ⚠️

🌿 What Should You Feed Instead?

For older or overweight horses, ideal feed plans include:

• 🌿 Low-starch, high-fiber hay (tested for NSCs)
• 🥄 Soaked beet pulp without molasses
• 💧 Senior complete feeds designed with low starch and added fat
• 🧴 High-fat calorie sources like flaxseed oil or stabilized rice bran

Always introduce feed changes slowly and monitor for signs of improved energy, coat quality, and GI health. ✅

📱 Ask A Vet for Feed Recommendations

Need help evaluating your horse’s diet? Visit AskAVet.com or use the Ask A Vet App to:

• 📊 Check NSC content of common feeds
• 🧠 Assess inflammation risk by age and condition
• 🥗 Build custom feeding plans for metabolic horses

Dr Duncan Houston and the Ask A Vet team can help you feed with science, not guesswork. 📲🐴

🏁 Final Thoughts

In 2025, we know that high-starch diets cause inflammation in horses—especially those who are older or overweight. Chronic inflammation isn’t just about gut health; it affects joints, the brain, and long-term vitality. By choosing low-starch feeds and individualized nutrition plans, you can protect your horse’s health and longevity. 🐴🔥🧬

Need a printable “Low-Starch Feed Guide”? Visit AskAVet.com to download yours today 📄📱