Cats can have some nuts, but generally, nuts are not safe or recommended for cats. Most nuts are not toxic, but they pose several risks: they can be a choking hazard due to their hard texture, may cause gastrointestinal upset, and their high fat content can lead to weight gain, pancreatitis, or other health problems. Some nuts are particularly dangerous for cats—macadamia nuts are toxic and should be completely avoided; walnuts and pecans can be harmful due to mold, which might cause severe symptoms. If a cat eats nuts, monitor them for choking or digestive issues, and avoid giving any nuts regularly or in large quantities to prevent health risks. It's safest to avoid feeding nuts to cats entirely because they do not provide valuable nutrition and can cause harm.