They are high in monounsaturated and polyunsaturated fats and omega-3 fatty acids. They are also a good source of protein. Nuts have a reputation for being a high-calorie and high-fat food. However, they are dense in nutrients and provide heart-healthy fats. The combination of healthy fats, protein, and fiber in walnuts helps to increase satisfaction and fullness. Walnuts are primarily made up of protein and polyunsaturated fat. They contain a relatively high percentage of omega-3 fat, which has been linked to various health benefits.

Vitamins and minerals.
Walnuts are an excellent source of several vitamins and minerals, including:

Copper. This mineral promotes heart health. It also helps maintain bone, nerve, and immune system function (11, 12Trusted Source).
Folic acid. Also known as folate or vitamin B9, folic acid has many important biological functions. Folic acid deficiency during pregnancy may cause birth defects.
Phosphorus. About 1% of your body is made up of phosphorus, a mineral that is mainly present in bones. It has numerous functions.
Vitamin B6. This vitamin may strengthen your immune system and support nerve health. Vitamin B6 deficiency may cause anemia.
Manganese. This trace mineral is found in the highest amounts in nuts, whole grains, fruits, and vegetables.
Vitamin E. Compared to other nuts, walnuts contain high levels of a special form of vitamin E called gamma-tocopherol (17Trusted Source, 18Trusted Source).