Anemia is a common blood disorder characterized by a deficiency in the number or quality of red blood cells (RBCs) or in the concentration of hemoglobin, a protein in red blood cells that carries oxygen from the lungs to the rest of the body. This deficiency leads to reduced oxygen flow to the body's organs and tissues, resulting in symptoms such as fatigue, weakness, shortness of breath, and pale or yellowish skin. Anemia can be caused by a variety of factors, including iron deficiency, vitamin B12 deficiency, chronic diseases, genetic disorders, and loss of blood. Treatment for anemia varies according to the underlying cause and may include dietary supplements, medications, procedures to control bleeding, or in severe cases, blood transfusions. Iron deficiency anemia is the most common type and is particularly prevalent among women of childbearing age due to menstruation and the increased iron demands of pregnancy. Testosterone plays a role in erythropoiesis (the production of red blood cells), and testosterone replacement therapy (TRT) has been shown to improve anemia in men with low testosterone levels. Monitoring and managing anemia is essential for individuals with chronic conditions or those undergoing treatments that may affect blood cell production, such as chemotherapy for cancer.