What Horses Should Never Eat: Dangerous Foods & Plants Every Owner Must Avoid

What Horses Should Never Eat: Dangerous Foods & Plants Every Owner Must Avoid

Horses have incredibly sensitive digestive systems, and even small amounts of the wrong food can cause colic, toxicity, or life‑threatening reactions. Whether you’re a new owner or just need a refresher, this guide covers the foods, plants, and household items horses should never eat — and why.


1. Human Foods That Are Dangerous for Horses

1. Chocolate

Contains theobromine, which is toxic to horses and can cause:

  • Colic

  • Seizures

  • Heart issues

2. Avocado

Every part of the plant is toxic. Can cause:

  • Breathing difficulties

  • Colic

  • Irregular heartbeat

3. Onions & Garlic (in large amounts)

Small amounts in supplements are fine, but large quantities can cause:

  • Anaemia

  • Weakness

  • Lethargy

4. Tomatoes & Potatoes

Members of the nightshade family. Can cause:

  • Gastrointestinal upset

  • Neurological issues

5. Bread & Bakery Products

They expand in the gut and disrupt digestion. Risk of:

  • Colic

  • Choke

6. Caffeine (tea, coffee, energy drinks)

Can cause:

  • Heart irregularities

  • Excitability

  • Toxicity


2. Toxic Plants Horses Must Avoid

1. Ragwort

One of the most dangerous plants for horses. Causes irreversible liver damage.

2. Yew

Extremely toxic — even a few mouthfuls can be fatal.

3. Foxglove

Contains digitalis, which affects the heart.

4. Bracken Fern

Long‑term ingestion causes vitamin B1 deficiency.

5. Sycamore Seeds & Seedlings

Cause Atypical Myopathy — often fatal.

6. Buttercups

Mildly toxic when fresh; can cause mouth irritation.

7. Oak Leaves & Acorns

Large amounts cause kidney and digestive issues.


3. Garden & Household Items to Keep Away From Horses

1. Lawn Clippings

Never feed grass cuttings. They ferment quickly and can cause:

  • Colic

  • Laminitis

  • Choke

2. Compost

Often contains moulds and toxic plants.

3. Mouldy Hay or Feed

Can cause respiratory issues and poisoning.

4. Decorative Plants

Common garden plants like:

  • Rhododendron

  • Privet

  • Laurel

  • Lilies

Many are toxic if eaten.


4. Stable Snacks That Are Safe (and Loved!)

If you want to treat your horse, stick to:

  • Carrots

  • Apples

  • Bananas

  • Peppermint treats

  • Horse‑safe biscuits

  • Fibre‑based treats

Always feed in moderation.


5. What To Do If Your Horse Eats Something Dangerous

Call your vet immediately if you suspect ingestion of:

  • Toxic plants

  • Mouldy feed

  • Human foods

  • Unknown substances

Do not wait for symptoms — early action saves lives.