As a hematologist, I can tell you that there are several factors that can lead to low hemoglobin levels. Hemoglobin is a protein in red blood cells that carries oxygen throughout the body. When levels are low, it can be due to various conditions that affect the body's ability to produce sufficient red blood cells or hemoglobin itself. Here are some of the key causes: 1. Aplastic anemia: This is a condition where the bone marrow does not produce enough new blood cells, including red blood cells. 2. Cancer: Certain types of cancer, especially those that affect the bone marrow, can reduce the production of red blood cells. 3. Medications: Some drugs can suppress the bone marrow's ability to produce blood cells. This includes certain anti-retroviral drugs for HIV and chemotherapy drugs for various types of cancer. Other causes can include: 4. Nutritional deficiencies: Lack of essential nutrients like iron, vitamin B12, or folic acid can lead to anemia. 5. Chronic diseases: Long-term illnesses such as kidney disease or rheumatoid arthritis can affect hemoglobin levels. 6. Hemolysis: The premature breakdown of red blood cells can result in low hemoglobin. 7. Blood loss: Acute or chronic blood loss, due to injury, surgery, or conditions like ulcers or heavy menstrual periods, can lead to low hemoglobin. It's important to diagnose and treat the underlying cause of low hemoglobin to address the issue effectively. read more >>

Diseases and conditions that cause your body to produce fewer red blood cells than normal include: Aplastic anemia. Cancer. Certain medications, such as anti-retroviral drugs for HIV infection and chemotherapy drugs for cancer and other conditions.read more >>