Pistachios are rich in copper, magnesium and all kinds of vitamins in group B, which strengthen the immune system and prevent many diseases. Vitamin B6 is essential for maintaining the immune system. Vitamin B6 deficiency leads to ineffectiveness of the immune system to fight infection. The use of pistachios helps to make red blood cells properly. Pistachio is one of the best sources of potassium, with its potassium content, with a small amount equal to orange potassium.