Donating blood frequently can definitely be the reason that you now have iron deficiency anemia.

Red blood cells are one of the main places that iron is stored in the body. So loss of blood is the leading cause of iron deficiency. Common ways for people to lose blood include:

• Silent bleeding from the digestive system. This includes the stomach (for example, ulcers) and colon (for example, polyps or cancer).
• Heavy menstrual bleeding.
• Major blood loss after a serious injury or surgery.
• Frequent blood samples for medical tests.
• Frequent blood donation.

Most people get enough iron in their diet. It’s uncommon for a lack of iron in the diet to be the only cause of iron deficiency anemia. But some people fail to absorb the iron in their food because of digestive problems, such as celiac disease. Or they have had stomach or intestinal surgery.

Pregnancy can also cause a woman to become iron deficient. The growing fetus takes iron from its mother, so she gets less.

Adults who develop new iron deficiency usually deserve a medical work-up to make sure they are not losing iron due to a serious medical problem, such as colon cancer. Since your medical work-up is normal, donating blood seems to be your only reason for anemia. So it makes sense to stop donating blood until your iron levels return to normal.

I assume you are now taking iron supplements. If you remain anemic despite taking them, you may need further evaluation.