They are one of the best sources of omega-3 fatty acids in nature. For those who do not eat fish is the best source of supplement. Help improve vision and sleep quality. Mono-polyunsaturated fatty acids help lower "bad" cholesterol and are good for the heart. They contain copper which is essential for bone health, phosphorus, manganese, vitamin E, vitamin B6 and help the proper functioning of the nerves. Walnuts are rich in antioxidants and healthy fats and can improve brain function and help memory.