The short answer: It is not recommended.
The long answer: There are a few nut varieties that your dog can enjoy (peanuts and cashews, to name a few), but there are more types that are dangerous for his well-being. Macadamias, for one, contain an undetermined toxin that may cause your dog to display any of the following symptoms within 12 hours of consumption: weakness, tremors, loss of muscle control, vomiting, hyperthermia, fever, and/or depression. Just six pieces of these can make your dog unwell. Walnuts, on the other hand, are large nuts that can block your dog’s airway or intestine. If they have been out for a long time, they may also contain molds that can trigger epileptic seizures.
Nuts are good sources of omega-3 fatty acids and protein, so it’s best to consult with your vet if your dog really needs it. If your doctor recommends that you include it in your dog’s diet, be sure to regulate how much he eats. You don’t want your pooch to become too fond of its taste and texture. A dog with a sensitive stomach or pancreatitis might vomit or have diarrhea if you feed him too much nuts.
What to do if your dog accidentally eats nuts: If you suspect that your dog ate some nuts, call your veterinarian or bring him to the clinic immediately. The treatment will depend on what kind of nut he has eaten, how much he has consumed, and other ingredients present with the nut he ate such as salt, sugar coating, or chocolate.
In summary: It’s best not to feed nuts to your dog, especially if you’re not sure they’re safe for him. Be careful how you store your nuts and where you eat them (i.e. on the couch), so that your dog doesn’t have easy access to them. Also, dispose of the hard shells properly. The sharp edges might accidentally tear your dog’s soft throat or stomach lining if he consumes them the wrong way.