The Surprising Benefits of Giving Blood

Less than 10 percent of eligible people actually donate blood each year. If you’re one of the elite few, congrats! Giving one unit of whole blood can save as many as three lives. The number one reason people give is to help others, according to the Community Blood Center, but there are plenty of other benefits to the donor.

Benefits of giving blood

“The biggest [benefit of donating blood] is the warm fuzzy one of being an altruistic person,” says Ross Herron, MD, divisional chief medical officer of the American Red Cross in Los Angeles. But being altruistic also brings physical health bonuses, among them lowering blood pressure, according to a study in Health Psychology. And you don’t even need to know the person to reap the rewards, says a study in Motivation and Emotion. “There are a lot of very positive mental aspects to knowing that you’ve done that much good basically by sticking out your arm and donating blood,” confirms Rita Reik, MD, chief medical officer of OneBlood in Fort Lauderdale.

Get a free wellness check

Every donor has to go through a physical assessment before giving blood. That includes checking blood pressure, pulse, body temperature, and hemoglobin levels. Some places also check your cholesterol. If you donate regularly at a certain organization, you can also see your trends over time through an online donor portal. It’s not a substitute for a thorough physical exam, but blood donation can provide useful information about your own health. (You may get a chance to nip high blood pressure or cholesterol in the bud.)

Find out if you have anemia

A hemoglobin test is done as part of the pre-donation process and lets you know if you have anemia. That’s when you don’t have enough red blood cells circulating in your body. According to Statistics Canada, 3 percent of the Canadian population have anemia. Having the condition can mean you have an underlying chronic condition or a vitamin deficiency and it can also cause irregular heartbeats, says the Mayo Clinic. The good news? It’s usually easily treatable.

Reduce iron levels

This isn’t such a big deal for generally healthy people, but for the one in 300 Canadians who have hereditary hemochromatosis, it is. People with hemochromatosis have high levels of iron which can eventually damage organs. Treatment for hemochromatosis includes regular phlebotomy—taking blood out of your system. “This is one category of patients that truly gets a therapeutic benefit from donating blood,” says Len Horovitz, MD, a pulmonary specialist with Lenox Hill Hospital in New York City. Bear in mind, you should also be under a doctor’s care for this condition.

Find out if you have an STD

Once the blood has been collected and the needle is out of your arm, all blood donations are automatically tested for a slew of different diseases, including syphilis and HIV, says Tom Neish, supervisor of the University of North Carolina (UNC) Blood Donation Center in Chapel Hill. The center will then let you know your status. Don’t immediately panic if you come back positive, though. The tests used are super sensitive and if you test positive, they’ll retest you. “The majority amount of times they are fine,” says Neish. “It’s a conservative testing platform.” However, if you think you already might have or be at risk for an STD, see your doctor—not a blood donation center. Never use blood donation as way to screen for STDs, the Red Cross emphasizes. (And give honest answers to the questions you will be asked about your sexual activity; centers can refer you to places that can perform STD tests.)

Find out if you have other infectious diseases

Blood donations aren’t just tested for STDs. They’re also tested for West Nile virus, hepatitis B and C, Zika, and Chagas’s disease (which is caused by a parasite). The same principle applies: Don’t freak out if you’re positive. You’ll get retested and, if you really are positive, you can get medical help, says Neish.

Boost your heart health

A study in the journal Transfusion found that people with hypertension who gave blood four times saw their blood pressure go down. There’s also a theory that higher iron levels may negatively affect your heart. The findings aren’t hugely robust, cautions Dr. Herron. And you shouldn’t ignore other treatments. Still, getting assessed as part of the donation makes you attuned to staying healthy. Read up on foods that help lower high blood pressure.

Burn (a few) calories

Okay, it’s not so many calories that you’ll actually shed pounds, but when else would you have an opportunity to use up some energy just lying there? And while you’re lying there, some centers, like the one at UNC, offer heated seats, free movies, and warm blankets. One donor likened it to a spa. No one knows how many calories or why, says Neish. So don’t make this your main reason for donating, obviously.

Learn your blood type

Giving blood will let you know which of the different blood types you have. The information could come in handy in the event of an accident or another emergency, says Dr. Horovitz. However, don’t worry about your memory, he says: Medical personnel can confirm your type. “It’s [also] a good idea to know what it is in case you want to donate for someone, say a friend,” says Dr. Horovitz.

Get involved in the process

Even though blood donations are anonymous, some centers are finding ways to make the donor more involved in the process. “There are apps [like this one from the Red Cross] that alert donors to when their blood donation has been used in real-time,” says Dr. Reik. “There are a lot of things to create more engagement between the donor and the recipient while maintaining anonymity. It’s a big boost to a person to know they’ve done something like that.”

Medically reviewed by Michael Spertus, MD.

Next, find out why type O is the most common blood type.