Low hemoglobin means your blood has fewer red blood cells or less hemoglobin protein than normal, which reduces its ability to carry oxygen to your body's tissues. This condition is most commonly associated with anemia
. When hemoglobin is low, your organs and tissues receive less oxygen, which can cause symptoms such as fatigue, weakness, shortness of breath, dizziness, pale skin, headache, and a fast heartbeat
. The severity of symptoms often depends on how low the hemoglobin level is. Common causes of low hemoglobin include:
- Iron deficiency, which is the most common cause since iron is essential for making hemoglobin
- Blood loss from heavy menstrual bleeding, gastrointestinal bleeding (ulcers, cancers), or frequent blood donation
- Vitamin deficiencies, particularly vitamin B12 or folate, which affect red blood cell production
- Bone marrow or stem cell problems that impair red blood cell production, such as aplastic anemia or cancers
- Genetic conditions like thalassemia or sickle cell anemia that affect hemoglobin structure or production
- Chronic diseases or inflammation that interfere with red blood cell production or lifespan
Low hemoglobin levels can range from mild to life-threatening. Levels below about 6.5 g/dL are considered serious and may require urgent treatment like blood transfusions
. In summary, low hemoglobin means your blood cannot deliver enough oxygen efficiently, often due to anemia caused by nutritional deficiencies, blood loss, bone marrow problems, or chronic conditions. Treatment depends on the underlying cause and may include supplements, managing bleeding, or other medical interventions
