Peanuts are rich in protein and vitamin E, they even have some “healthy” fats. Although birds can eat peanuts (cooked/roasted and no-salt), it is not recommended to feed too much to birds because peanuts contain aflatoxin. Eating too much aflatoxin can increase the incidence of liver cancer.
Care For Your Birds - Beginners' Guide【新手飼養雀鳥指南】 