Understanding Hemoglobin and Iron Levels

Your body needs iron to make a protein called hemoglobin. Because hemoglobin carries oxygen throughout your body, if you do not have enough iron, your body makes fewer red blood cells.

We take your health to heart.

Every day hundreds of patients in the communities we serve require blood transfusions, and we greatly appreciate your assistance in meeting the needs of these patients. By giving blood, you have shown your willingness to care for others. We at LifeSouth encourage you to also take good care of yourself, and recommend telling your primary physician that you donate blood and how often you donate.

Why does LifeSouth check my hemoglobin before a blood donation?

We measure your hemoglobin to make sure that giving blood will not reduce your hemoglobin to unsafe levels. Your hemoglobin level must be at least 12.5 grams per deciliter if you are female or 13.0 grams per deciliter if you are male. If your level is too low, then LifeSouth requires that you wait at least one day before attempting to donate again.

What does a low hemoglobin mean?

A hemoglobin less than the level required for donation does not necessarily mean that you have a disease or your result is clinically abnormal. Hemoglobin levels may vary according to your age, race, gender, genetic factors and lifestyle. The hemoglobin value that we measured today may be perfectly normal for you, even though the regulations say that it is too low to be a blood donor. However, if your hemoglobin is significantly lower than the cutoff ranges, this may be a sign of anemia.

When can I donate again?

Sometimes donors deferred for low hemoglobin return the next day and are eligible to donate. Please monitor how you feel, choose a donation schedule that is healthy for you, and work with your doctor on maintaining healthy hemoglobin and iron levels while donating blood.

If I have low hemoglobin, do I have iron deficiency anemia?

Low hemoglobin may be an indication that iron stores in your body are low. However, hemoglobin and iron are not the same. Even with a low hemoglobin it is possible that your iron stores are adequate. Although LifeSouth does not measure your iron stores, your doctor may choose to order special tests to determine whether you have iron deficiency anemia.

How does blood donation affect my iron levels?

When you donate blood, you lose some of your red blood cells as well as some of your iron. For most donors, their bodies are able to replace these lost cells and use some of their iron stores. However, if your iron stores are low prior to donation, or if you donate frequently, you may become iron deficient and need to replace some of your lost iron.

How do platelet and plasma donations affect my iron?

The amount of iron lost with these donations is far less than a whole blood donation or double red cell donation. However, for every 4 to 5 platelet or plasma donations you will lose the same amount of iron as a whole blood donation.

Who is at increased risk for iron deficiency after blood donation?

Young donors (16 to 18 years old), premenopausal females, frequent donors, and donors with hemoglobin values near the cutoff for donation may be at increased risk of developing iron deficiency. As a precautionary measure, 16 to 18 year old female donors who give whole blood or red blood cells must wait 16 weeks until their next donation.

What can I do to replace my iron stores?

While eating iron-rich foods may help replace some of the iron lost by blood donation, recent research has shown that dietary changes alone cannot adequately replace iron lost by blood donation. Studies have shown that taking an iron supplement, or multivitamin, that contains 18-38 mg of iron for 8 weeks (60 days) can replace the amount of iron lost in a whole blood donation. If you are a frequent donor or are at risk for having low iron stores, taking an iron supplement is highly encouraged following blood donation. You should talk to your pharmacist or physician prior to starting an iron supplement, especially if you are currently on any medications, have underlying medical conditions, are 65 years of age or more, or have a family history of hereditary hemochromatosis, familial polyposis or colorectal cancer.

Important definitions:

  • Frequent Donor:  If you are a male and donate whole blood 3 or more times a year, or if you are a female and donate whole blood 2 or more times a year, you may deplete your body’s natural iron stores.
  • Hemoglobin:  Hemoglobin is the protein in your red blood cells responsible for carrying oxygen from the lungs to the tissues in your body. It is also responsible for the characteristic red color of these cells. Iron is an important building block of this protein.
  • Iron stores:  Iron is stored in your cells and tissues, including red blood cells, liver, and bone marrow. When your body detects a shortage of iron, these stores can be used to help continue normal red blood cell production. For example, if you do not get enough iron in your diet, your body can ensure there is an adequate amount available by tapping into these iron stores.
  • Iron deficiency anemia:  Anemia is a condition in which the number of red blood cells or their oxygen-carrying capacity is insufficient to meet physiologic needs. Iron deficiency anemia is one type of anemia that is due to very low, or absent, stores of iron and a resulting shortage of the iron building block needed to produce red blood cells. Mild to moderate anemia may cause few to no symptoms. Symptoms of more significant anemia can include fatigue, difficulty concentrating, restless legs, and a craving to chew ice.