what makes hemoglobin low
Another term frequently used in place of low hemoglobin is anemia, or the person is described as being anemic. Some of the more common causes of anemia are as follows: 1  Nutritional (iron, folic acid, or vitamin B 12 deficiency [ pernicious anemia 2  ]). Gastrointestinal blood loss (ulcers, colon cancer). 3  Kidney problems.