Are Walnuts Safe for Dogs to Eat?
If you're wondering whether your dog can snack on walnuts, the answer is complicated—and mostly negative. While some nuts are less dangerous than others, walnuts carry several risks that make them a poor choice for canine treats.
Types of Walnuts and Their Risks
There are two main types of walnuts you might come across: English walnuts (the common store-bought kind) and black walnuts. Each poses different dangers:
- English Walnuts: These aren't toxic to dogs when fresh, but they're high in fat, hard to digest, and pose choking or blockage hazards—especially for small breeds.
- Black Walnuts: Highly toxic to dogs. They contain juglone, a compound that can cause vomiting, tremors, seizures, or even death.
The Dangers of Moldy Walnuts
Moldy walnuts—whether found outside or left too long in the pantry—are especially hazardous. They may contain mycotoxins like aflatoxins and penitrem A. Ingesting these toxins can lead to muscle tremors, seizures, liver damage, or fatal outcomes. Never let your dog eat old or fallen walnuts from the ground.
Physical Hazards: Choking and Blockage
Walnut shells are tough and indigestible. If swallowed by a dog (especially smaller breeds), they can cause intestinal obstructions—a potentially life-threatening emergency. Even shelled walnuts are large and difficult for dogs to chew thoroughly.
Symptoms of Walnut Toxicity or Blockage
- Vomiting
- Diarrhea
- Lethargy or weakness
- Loss of appetite
- Tremors or seizures
- Abdominal pain
If your dog shows any of these signs after eating a walnut (or any nut), seek veterinary attention right away.
The Problem with High-Fat Foods Like Walnuts
Nuts are fatty foods. Too much fat can trigger pancreatitis in dogs—a painful condition that causes inflammation of the pancreas. Dogs with a history of pancreatitis or sensitive stomachs should never be given nuts.
Puppies Are Especially at Risk
Puppies have developing digestive and immune systems. They're even more vulnerable to the hazards posed by nuts—including walnuts—and shouldn't be given any at all.
If Your Dog Eats a Walnut: What Should You Do?
- If it was just one English walnut and your dog is healthy, monitor closely for symptoms listed above.
- If it was a black walnut, moldy walnut, or included the shell—or if your dog is small or has pre-existing health issues—call your veterinarian immediately.
If you're unsure what type of walnut was eaten or if any symptoms develop, err on the side of caution and contact your vet.
Nuts in General: Not Great for Dogs
- Macadamia nuts: Very toxic; never feed them to dogs.
- Pecans, almonds, Brazil nuts, hazelnuts: Not toxic but still risky due to fat content and potential for blockage or mold contamination.
If you ever give your dog nut-based treats (not recommended), they should be plain, unsalted, free from additives like xylitol (which is highly toxic), and offered only in tiny amounts—but it's safer to skip them altogether.
The Bottom Line: Safer Treat Options Exist
The safest route is simply not feeding your dog walnuts—or nuts in general. There are plenty of healthier treats specifically designed for canine nutrition that don't carry these risks. If you're considering new foods for your pet's diet, talk with your veterinarian first.
