The peanut (Arachis hypogaea) is botanically considered a pea and belongs to the legume family. However, it has all the characteristics of a nut and is an oil seed. It also has more protein than any other nut.

Peanuts are an excellent source of antioxidants such as resveratrol, phenolic acids and flavonoids. They also have coenzyme Q10. They contain all 20 amino acids, and in higher amounts arginine. These bioactive compounds have disease-preventing properties and are believed to promote longevity. Diets high in monounsaturated fats, such as those found in peanuts - but also in other nuts and olive oil - reduce triglycerides, total cholesterol by 11% and (bad) LDL cholesterol by 14%, while maintaining (good) HDL cholesterol. The benefits of a peanut diet on cholesterol are comparable to an olive oil diet. Strong evidence supports the association between monounsaturated fat from nuts and a reduced risk of coronary heart disease. Peanuts have the highest level of arginine of any food. Arginine (or L-arginine) is an amino acid needed for the maintenance of healthy liver, skin, joints, and muscles. It helps boost the immune system, regulate hormones and blood sugar, and promote male fertility.