Iron pills can help boost hemoglobin level after blood donation

Q: I donate blood about four times per year. My most recent blood count was a bit low and the blood bank told me to wait another month. What can I do to build up my blood?

A: That's terrific that you're a regular blood donor!

Each time you give blood, the technician will first check your hemoglobin level. It must be at least 12.5 grams per deciliter before you can donate.

Hemoglobin is made up of iron and protein. It's the part of red blood cells that carry oxygen throughout the body. To keep hemoglobin levels normal, you need to have enough iron in your body.

When you donate a pint of blood, you lose about 230 milligrams of iron. Your small intestine responds to the loss of iron by absorbing more iron from your foods. But it takes two to three months and sometimes longer to regain all the iron stores. Most likely, your intestines didn't have enough time to absorb enough iron to get you to the 12.5 hemoglobin level.

Results of a recent study showed that taking iron pills can help boost hemoglobin levels after blood donation. The report was published in the Journal of the American Medical Association on Feb. 11.

Iron pills can sometimes cause an upset stomach and constipation. Of the different preparations, ferrous gluconate is usually the best tolerated. That's why it was chosen for this study.

One standard 325 milligram ferrous gluconate pill daily should be sufficient. Each pill contains 37.5 milligrams of elemental iron.

To get optimal iron absorption, take the pill with orange juice or 250 milligrams of vitamin C one hour before eating. If you do experience nausea or stomach upset, it's fine to take your pills with food. But don't take them with milk, antacids or calcium; these do block absorption.

Don't be alarmed if your stool gets very dark; it's from the iron.

(Howard LeWine, M.D., is an assistant professor of medicine at Harvard Medical School and Brigham and Women's Hospital in Boston. He serves as Chief Medical Editor of Internet Publishing at Harvard Health Publications.)

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