Here is a list of human foods that are bad for dogs.
Onions, garlic, avocado, coffee, nuts, raisins, grapes, salt, bread and chocolate.
There is some evidence that garlic is beneficial to dogs. It’s lumped in because it’s an onion relative, and onions are bad for dogs. But, I’ve given mine foods with garlic, even garlic tabs before. Good for natural flea repellent, helps their immune function. They’ve all lived long lives.
I came downstairs to find our dog had gotten two avocados off the table, but didn’t eat them in the kitchen, no, she took them in the family room and left the shredded peel all over the carpet, licked clean.
Internet searches showed the only serious problem would be if she ate the pits and they caused an obstruction, but she left those. Some dogs might vomit or have loose stools, but she didn’t. There are lots of people with avocado trees who let their dogs forage the windfall with no harmful effects.
It does cause heart failure in birds, though, so no avocado for the parakeets.