Cashews are a close relative of mangos and pistachios and are nutritionally dense, with 5 grams of protein per ounce and high levels of the minerals iron, magnesium, phosphorus, zinc, copper and manganese. They have a relatively high fat content but it is considered good fat due to the combination of saturated, monounsaturated, and polyunsaturated, respectively, which scientists agree is good for optimal health. Even with the relatively high fat content, cashew nuts are considered to be low-fat. They also have a high energy density and dietary fiber, a positive element in weight management when eaten in moderation.