What to Do If You Can't Donate Blood Due to Low Hemoglobin Levels

blood donations

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Key Takeaways

  • Both the United States and Canada are experiencing dire blood shortages and calling for more blood donors.
  • However, if your hemoglobin levels are too low, you might be turned away from your appointment.
  • Hemoglobin levels can usually restore to a normal range over time, but you can also focus on eating an iron-rich diet or taking supplements if needed.

Earlier this year, the American Red Cross said it was facing the worst blood shortage in over a decade, calling it “a national blood crisis.” Canadian Blood Services issued a similar statement in August, saying the number of people donating had hit a 10-year-low. 

After watching my grandfather receive many blood transfusions before his death in November of 2021, I wanted to donate blood in his honor despite my fear of needles. Months went by and I became preoccupied with other things, forgetting about my intention to donate, but the news of blood shortages throughout North America reignited my desire to become a donor. 

I finally made an appointment at the end of August, filling out all the necessary documents to ensure I was eligible. I arrived at my appointment days later and spent roughly an hour going through the registration process before the worker pricked my finger, tested my blood, and informed me that my hemoglobin levels were simply too low to donate. 

Though she assured me that I could try again in three months, I left confused and disappointed about my failed attempt at giving back. 

Why Hemoglobin Levels Matter

Hemoglobin contains iron, which is necessary to generate new red blood cells. Blood centers have a minimum hemoglobin level to ensure that your hemoglobin and iron won't drop to a dangerously low level after donating blood.A deficiency in iron may make you feel tired or lead to anemia, while extremely low iron could cause damage to organs.

Reasons for Low Hemoglobin Levels

Hemoglobin is a protein in red blood cells that contains iron and transports oxygen in the bloodstream. When I was turned away by the Canadian Blood Services, I was told that low hemoglobin levels are quite common in people who menstruate.

Liudmila Schafer, MD, FACP, a board-certified and award-winning medical oncologist, said menstruation causes a loss of iron, which is an important component of hemoglobin. Heavy menstruation can also lead to “chronic” blood loss, she said, causing the number of red blood cells to be lower than normal. A poor diet or anemia can also lead to low iron.

Other demographical factors might also come into play, she said, such as race and ethnicity. For example, research shows that the average hemoglobin level is naturally lower in Asian people and Black people compared to that in White people.

You could also have low hemoglobin levels if you donate blood too frequently, Schafer added. You should always wait at least three months between donations, because it takes the body an average of 90 days for red blood cells to regenerate.

If you’re still unsure why you have low hemoglobin levels, you can discuss with your healthcare provider about checking for ulcers, bleeding, thyroid function, or hemorrhoids.

Hemoglobin Levels for Blood Donations

According to the American Red Cross, the normal hemoglobin range for men is 13.5 to 17.5 g/dL, while the normal range for women is 12.0 to 15.5 g/dL. The range for African Americans—men and women— varies by 0.7 g/dL at the low end of the range.

How to Raise Your Hemoglobin Levels

Low hemoglobin levels usually aren’t caused by anything serious, Schafer said, and they often improve naturally over time.

You can also boost your hemoglobin levels by eating an iron-rich diet, she said. Foods such as meat, fish, poultry, beans, and leafy greens all contain high amounts of iron.

Since vitamin C helps the body absorb iron, you can also consider eating more foods that are rich in vitamin C, such as tomatoes, oranges, and bell peppers.

If necessary, your healthcare provider might be able to prescribe iron supplements. According to the American Red Cross, teenagers and frequent blood donors may benefit from “an iron supplement with 18–38 mg of elemental iron or a multivitamin with 18 mg of iron for at least 60 days after donating whole blood or 120 days after a power red donation.”

“Because we are facing such a shortage, we need more people to donate blood, so it’s more important than ever to understand your Hb levels and donate if you can,” Schafer said.

What This Means For You

If you try to donate blood but get turned away due to low hemoglobin levels, don’t be alarmed. Most of the time, your levels will restore gradually. To help with this process, focus on eating an iron-rich diet, and take supplements if your doctor says it’s necessary. You can try donating again in three months.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Blood Donor Counselling: Implementation Guidelines. Geneva: World Health Organization; 2014. Annex 1, Haemoglobin and iron: information for blood donors.

  2. Lim E, Miyamura J, Chen JJ. Racial/ethnic-specific reference intervals for common laboratory tests: a comparison among Asians, Blacks, Hispanics, and WhiteHawaii J Med Public Health. 2015;74(9):302-310.

  3. American Red Cross. What donors should know about iron and blood donation.

By Mira Miller
Mira Miller is a freelance writer specializing in mental health, women's health, and culture.