Can Cats Eat Walnuts? 2026 Safety Guide
❌ Quick Answer: No — Walnuts is not recommended (or is toxic) for cats. Avoid feeding this food.
Read on for the full breakdown — including how much is safe, preparation tips, and when to call your vet.
Is Walnuts Safe for Cats?
The short answer is no — walnuts carries real risks for cats that make it not worth offering, regardless of how much your pet wants it.
If your cat has already eaten walnuts, see the FAQ section below for guidance on what to do.
Nutritional Benefits (If Any)
While Walnuts may have some nutritional properties, they do not outweigh the risks for cats:
- Some omega-3 fatty acids (ALA)
Risks and Concerns
- Black walnuts contain juglone — toxic to cats
- English walnuts prone to mold producing tremorgenic mycotoxins
- Very high fat — pancreatitis risk
- Hard texture can injure mouth and GI tract
How to Serve Walnuts to Your Cat
Not recommended. The risk of mold toxicity, juglone, and pancreatitis makes walnuts a poor treat choice when safer foods exist.
Key preparation rules:
- Always introduce new foods slowly — start with the smallest amount listed below
- Watch for vomiting, diarrhea, lethargy, or other changes over 24 hours after first introduction
- Consult your vet before introducing new foods if your cat has health conditions
Safe Serving Sizes
| Cat Size | Safe Serving Amount |
|---|---|
| All cats | Not recommended — avoid |
*Treats and supplementary foods should make up no more than 10% of your cat’s daily caloric intake. Consult your veterinarian for personalized guidance.*
When to Call Your Vet
Contact your veterinarian if your cat experiences:
- Persistent vomiting or diarrhea (more than 2–3 episodes or lasting longer than 12 hours)
- Lethargy or unusual behavior after eating Walnuts
- Signs of an allergic reaction (facial swelling, hives, difficulty breathing)
- Seizures, tremors, or loss of coordination — these require immediate emergency care
Emergency resources:
- ASPCA Animal Poison Control Center: 888-426-4435 (24/7)
- Pet Poison Helpline: 855-764-7661 (24/7)
Frequently Asked Questions
Are walnuts from my tree dangerous for my cat?
Yes — if you have a black walnut tree, even contact with fallen nuts and hulls can cause toxicity in cats. Black walnut juglone is toxic to cats, dogs, and horses. Keep cats away from black walnut trees.
What about English walnuts from the grocery store?
English walnuts (the common grocery store variety) are not directly toxic in the same way as black walnuts, but they’re frequently contaminated with Aspergillus mold that produces aflatoxin and tremorgenic mycotoxins. Not safe for cats.
Can a small piece of walnut hurt my cat?
A single piece of fresh English walnut flesh is unlikely to cause acute toxicity, but the risk of mold contamination makes even occasional feeding inadvisable. Choose safer treat options.
Are walnuts toxic to cats like macadamia nuts are to dogs?
Walnuts don’t have the same established toxicity mechanism as macadamia nuts do for dogs. The primary concerns for cats are juglone (black walnuts), mold contamination, and high fat content rather than a breed-specific toxin.
*Affiliate disclosure: GetPetPros.com participates in affiliate programs. We may earn a commission if you purchase through links on this page, at no extra cost to you. All content is based on independent research and is not a substitute for professional veterinary advice.*