13 Things You Should Know Before Donating Blood

Updated: Mar. 14, 2022

Donating blood is an incredibly noble cause, however, there are some things you should know before you hand your arm over.

Blood donation
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Blood donation facts

There are many reasons to donate blood, not the least of which is that it can be a lifesaving and selfless act. At the moment, blood donations are urgently needed due to the Covid-19 pandemic, as well as more surgeries and procedures taking place that were temporarily delayed due to the coronavirus. (In fact, the Red Cross is now offering free Covid-19 antibody tests to people to encourage blood donations.)

If you are thinking about becoming a blood donor, here are some donation facts you need to know before making your way to the American Red Cross.

Blood transfusion to a patient in the hospital
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In the United States, a blood transfusion is needed every two seconds

It’s estimated that one in seven people entering a hospital needs blood, according to The Red Cross. To keep up with this demand, the American Red Cross must host over 500 blood drives a day to collect nearly 13,000 units needed for hospital patients. (Here’s what happens to your blood after you donate it.)

Portrait of a beautiful hispanic woman smiling while getting a blood test in a laboratory. Woman in a white coat gives blood in the clinic. A doctor is taking a blood test from a female patient.

Not everyone is eligible to donate blood

Safety restrictions mean you might not be able to donate blood. The basic requirements include being at least 17 years old to donate, but some states allow you to be 16 years old with parental consent, weighing at least 110 pounds (however, there is a height and weight requirement for donors younger than 18 years old) and a blood pressure reading above 90/50 and below 180/100, explains Cedrina Calder, MD, preventative medicine doctor and health expert.

Additionally, she points out that your blood count must be above a certain level and, if you are a female, you must not be pregnant.

cotton closed on men arm after blood samples for examination

There are a few, mostly minor, risks associated with donating blood

Risks associated with blood donation include bruising around the needle site, a sore arm, feeling dizzy, tired or weak, or irritation to nerves, according to Dexter Emoto, an RN at Loma Linda University Health who has personally donated 108 gallons of blood. Additionally, he points out that iron deficiency is common in donors, since every time you donate blood, the body loses a small amount of iron.

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The health of the donor matters

In the months, weeks, and days leading up to your donation, it’s vital that you maintain proper health, eat the right foods, stay hydrated, and get enough rest. “These steps may help you avoid being asked to wait to donate,” says John Hackett Jr., PhD, divisional vice president of Applied Research and Technology for Abbott. “After you donate, eat iron-rich foods like red meat, fish, poultry, beans, spinach, iron-fortified cereals, or raisins to help your body quickly replace the blood cells that donated.” (Don’t miss these strange facts about the human body you never knew about.)

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Avoid donating if you have certain acute or chronic conditions

If you’re fighting an illness such as a fever, cough or respiratory infection, you should hold off on donating until it resolves. It’s also important to note that if you have active tuberculosis, even if you are being treated for it, you cannot donate; however, Dr. Calder points out that you may donate if you have tested positive for tuberculosis with no active infection and you’re not on antibiotics. “If the infection is not active, but you are on antibiotics because you tested positive, you can donate after finishing the antibiotics.”

Underwear or Underpants and clothing for men on white wooden background

You are not eligible to donate if you have an STD

Individuals who have contracted hepatitis B, hepatitis C, chlamydia, herpes, genital warts, or HIV cannot donate blood. If you have gonorrhea or syphilis, you must wait 12 months after your treatment is completed,” says Dr. Calder. In guidelines set by the FDA for all U.S. blood collection organizations, “a man who has had sex with another man during the past 12 months” is not eligible to give blood.

Patient getting blood transfusion in hospital clinic

Giving blood is easier than you think—but come prepared

It only takes about an hour to give blood, but the process involves more than just extending your arm. “The first few minutes are for registration, including signing in with your identification and reading information about the process, and then approximately 15 to 20 minutes is spent discussing your health history, which will involve a few questions about how you feel, where you’ve traveled and any medications you’re taking ” says Dr. Hackett, Jr. “Then staff will check your temperature, pulse, blood pressure, and hemoglobin level, a protein in your body that contains iron and carries oxygen to your tissues.” The actual donation itself only takes eight to ten minutes.

Senior Patient Having Consultation With Doctor In Office
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You’re never too old to donate blood

While in most states, you must be at least 17 years old to donate blood, there is no upper age limit. In fact, as Pampee Young, MD, PhD, chief medical officer of the American Red Cross points out, many elderly individuals are some of the most dedicated blood donors.

“We encourage others to join them in helping ensure blood products are available for people in need,” she says. “All donors must bring a government-issued ID to show proof that they meet the minimum age requirements and for identification purposes.”

Human blood in storage

You don’t need to know your blood type

“According to a national survey conducted in April 2018, on behalf of the Red Cross, more than 53 percent of people believe they need to know their blood type to donate blood—this is simply not true,” says Dr. Young. “We need donors of all blood types to ensure a sufficient supply for patients.” If you’re looking to learn your blood type from your donation, you can request to be notified following your donation when you receive your blood donor call or by creating a profile through the Red Cross Blood Donor App.  (These are the secrets your blood type reveals about you.)

a bag of transfusion blood

There are benefits to blood donation that go beyond saving lives

You yourself benefit when you donate: “Blood donation helps cardiac health by improving circulation. Some reports also indicate less incidence of cancer in regular blood donors,” says Marisa Saint Martin, MD, assistant professor Loyola University Health System, Medical Director Pathology and Laboratory Services Gottlieb Memorial Hospital, Associate Director Blood Bank and Apheresis Services Loyola University Medical Center. “Additionally, we should not discount the mental health and spiritual benefits of being a volunteer and helping others, since volunteers in general report feeling more gratitude and joy in life.”

blood in glass tubes on background of microscope
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Only 5 to 6 percent of eligible donors actually donate

Dr. Saint Martin points out, without the generosity of this small segment of the population, medicine as we know it would not be possible. “Currently, there is no viable and/or practical substitute for blood—in other words, it cannot be manufactured,” she says. “Blood donors make possible many life-saving scenarios, including the survival of patients with cancer and congenital hemoglobin diseases, the support of surgeries (including gynecological), and the support of organ transplantation and trauma cases.” Find out the rarest blood type in the world.

13 Things You Should Know Before Donating Blood
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You don’t have to make an appointment

All eligible individuals can make an appointment by using the free Red Cross Blood Donor App, visiting RedCrossBlood.org or calling 1-800-REDCROSS (1-800-733-2767). But even if you can’t donate, you can still help the cause. “We also need organizations to host blood drives over the coming months too,” says Dr. Young. “In fact, more than 80 percent of donations are made at blood drives organized by volunteer sponsor groups and coordinators.” To learn more about hosting a blood drive and to sign up to sponsor a drive, visit RedCrossBlood.org/HostADrive.

Nurse taking care of a transfused patient in hospital ward

Donating blood is about paying it forward

You might not score a tax deduction for donating blood, but donating blood is a noble act. It’s truly done out of the goodness of the donor’s heart. “As a nurse, I care for patients who may need a blood transfusion, and I have the opportunity to administer the blood that has been donated by a volunteer blood donor to save a life,” says Dr. Emoto. “Being on both sides of the spectrum is a rare opportunity—we give to unknown recipients in need of a transfusion that may save her or his life.” Next, find out the incredible things the human body does every minute.