CAN DOGS EAT WALNUTS?
Walnuts themselves have mild toxicity for dogs, but moldy walnuts are far more dangerous — they contain tremorgenic mycotoxins that cause severe neurological symptoms.
Can Dogs Eat Walnuts?
Why?
Plain, fresh English walnuts carry some risk: they are high in fat (pancreatitis risk) and contain juglone, a phenolic compound that can cause GI irritation. In large amounts, juglone may cause mild neurological effects. However, the greater danger comes from black walnuts and from mold.
Moldy walnuts — including those that have fallen from trees and sat on wet ground — can harbor Penicillium and Aspergillus species that produce tremorgenic mycotoxins. These toxins cause severe muscle tremors, seizures, and hyperthermia that require emergency veterinary care. The mold is not always visible.
Dogs who scavenge fallen walnuts from walnut trees in autumn are at risk. The combination of juglone (the nut itself), mold toxins (from decay), and high fat content makes walnuts a food to avoid entirely.
How much is dangerous?
Moldy walnuts: even small quantities of highly moldy nuts can cause serious tremors. Fresh walnuts: moderate amounts can cause GI upset; pancreatitis risk from fat at any amount.
What are the symptoms?
- muscle tremors
- ataxia (staggering)
- seizures
- hyperthermia
- vomiting
- lethargy
- weakness
What should I do?
If your dog ate walnuts from the ground or walnuts that appear moldy, contact your vet immediately. Fresh, non-moldy walnuts in small amounts — call your vet for guidance on the quantity consumed.
Frequently asked questions.
Can dogs eat a couple of fresh walnuts?
A small amount of fresh, non-moldy English walnut is unlikely to cause serious toxicity, but the high fat content risks pancreatitis. There are better treats available.
Are black walnuts more toxic than English walnuts?
Yes. Black walnuts contain higher concentrations of juglone and are more likely to cause neurological symptoms even without mold.
Disclaimer: This information is for educational purposes only and does not constitute veterinary advice. Every dog is different. Always consult your veterinarian before making changes to your dog's diet or in the event of a potential poisoning emergency.