Walnuts are rich in various nutrients and fats, making them prone to spoilage. If dried walnuts have been stored for three years without proper care, it is not recommended to eat them, as they may have become stale, moldy, developed an off-odor, or even lost their beneficial nutrients.
Furthermore, three years can also lead to the loss of trace elements such as copper and iron, negating the health benefits that dried walnuts should provide. It is advisable to check the appearance of dried walnuts before consumption. If any changes are found, such as mold, off-odor, or discoloration, they should be discarded immediately.
