The true issue with avocados? The skin and leaves, which contain persin, an oil-soluble toxin that can be dangerous to non-human mammals. The ASPCA says that pets sensitive to persin may experience “respiratory distress, congestion, fluid accumulation around the heart, and even death.”
Avocado is safe if you avoid the skin and leaves—so it’s ok as an ingredient in dog foods, for example. In general, dogs are not as susceptible to persin poisoning as animals like horses, but it’s better to be safe than sorry.
3. Macadamia Nuts
Nobody’s sure exactly what about macadamia nuts is toxic to dogs, only that they can cause vomiting, ataxia (the loss of control of body movements), weakness, and depression. In other words, macadamia nuts can make dogs very, very ill.
Thankfully, most dogs recover without any specific treatment. So if your pup accidentally eats a macadamia nut, a full recovery is expected.