Anemia is a blood disorder that can occur when hemoglobin is unable to carry oxygen to the tissues. One cause of anemia is a deficiency in

Iron is needed to make hemoglobin, the protein in red blood cells that carries oxygen. If the body lacks enough iron, it may produce too little hemoglobin, causing iron-deficiency anemia. Calcium, potassium, and carbon are not the nutrient deficiency typically responsible for this form of anemia.

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