Hamsters can safely eat many types of nuts, including pistachios, peanuts, walnuts, cashews, hazelnuts and pecans, according to Hamster Club. While most nuts are fine for hamsters, almonds contain cyanide and can cause death if too many are consumed, according to Small Animal Channel.
About.com recommends limiting the amount of nuts and treats to 10 percent of a hamster's diet. For example, a healthy pellet diet and one or two unshelled peanuts every other day is more than enough for the average hamster. Hamsters should never consume any nut butters, such as peanut butter or cashew butter. Nut butters are sticky and can stick to a hamster's cheek pouches.