Alopecia Areata is an autoimmune condition that causes both men and women to lose their hair. This is because Alopecia Areata causes a person immune system to infiltrate and attack their hair follicles. Although, 6.6 million people will have this condition within their lifetime, scientists still do not know what causes a person to have it. The people who normally get it are individuals who are destined genetically or individuals who live extremely stressful lifestyles.