Myths and facts about donating blood, and how it could reveal clues about your own health

The American Red Cross declared its second-ever national blood supply crisis this summer amid a shortage that's threatening patients around the country. Blood has a short shelf life, and only 3% of eligible donors give blood regularly. Summer accidents and emergencies can put an already-strained stock at risk, and regular donors may skip their appointments, compounding the problem.  

We sat down with Dr. Courtney Lawrence, the divisional chief medical officer at the organization, to talk about the importance of blood donation, the myths and facts around the process and how donating can reveal information about your own health. 

How blood shortages put women at risk 

Women can be more affected by a blood crisis than men, because they are more likely to need a transfusion, Lawrence said. There are a number of reasons why. 

Women have lower hemoglobin than men, on average. Hemoglobin levels are one of the pieces of data doctors use to determine when a blood transfusion should be done. Because women's levels are lower on average, there "can be a period where they're more likely to need blood transfusion," Lawrence explained. 

There are also certain risk periods, like pregnancy, where women are more prone to anemia, and childbirth, where emergencies may necessitate a blood transfusion, Lawrence said. 

The key health information blood donation reveals 

Blood donors undergo a brief health screening before each donation. It collects data about a person's weight, blood pressure and other data about their blood. While that screening is short, it can reveal key health information. 

Donors who use the Red Cross app can even track that data. 

"We know at least a third of the population does not get in regularly to see a primary healthcare provider. So that's a lot of people who don't have a constant touch point with a physician or a nurse practitioner and some of them may come in to donate blood every two months," Lawrence said. "We're a frequent touch point and this is already information that we need because we want to make sure that we're keeping our donors safe when they come in to donate." 

"So if we're already checking these parameters, their heart rate, their blood pressure, their hemoglobin, this health history, why not make that information also accessible and trackable to those donors, so that if we do find that there's something that could benefit from a healthcare provider intervention, then they can take that information back to their healthcare provider and already have it accessible to them?" she added. 

There is also emerging research that shows giving blood can improve your overall health. Some small studies show that giving blood regularly can help control your blood pressure, Lawrence said. Donating blood also temporarily lowers your iron levels. Some studies show this can help some individuals improve their heart health, Lawrence said. 

One thing donating blood can't do, Lawrence said, is help prevent cancer, despite viral claims. Sometimes, tests can show irregularities that prompt people to get checked out by a doctor, but it's "certainly not the primary reason that we have people come in and screen," Lawrence said. 

Breaking down blood donation myths 

After our conversation, Lawrence took a few minutes to weigh in on some of the most popular myths surrounding blood donation. Here's what to know. 

• "I have a tattoo or permanent makeup, so I can't give blood." Whether you can donate after getting tattooed depends on if you go to a tattoo facility that is state regulated, Lawrence said. If the facility is regulated, you can donate again within three months. If it is not, you may be deferred. 
• "I don't have a rare blood type, so my blood donation isn't really needed." This is "absolutely not" true, Lawrence said. "Regardless of what your blood type is, there is a patient out there that would benefit from it." 
• "I have high blood pressure, so it's too dangerous for me to donate blood." This is generally false, Lawrence said. The donor screening would catch a blood pressure level that is too high to safely donate. If you have high blood pressure that's under control, "you are free to come in and donate blood," Lawrence said. 
• "I have diabetes or I am taking a GLP-1 medication, so I can't give blood." This is also generally false, Lawrence said. Those with well-controlled diabetes can donate blood. People taking Food and Drug Administration-approved diabetes treatments, including GLP-1s, can donate blood. 
• "You should fast before giving blood, similar to a blood test." This is absolutely false, Lawrence said. Eat a hearty meal and stay hydrated to "set yourself up for success" with your donation. 
• "Giving blood can make you anemic." This is generally false, Lawrence said, though regular donors should talk with their primary care physician to ensure they don't need more iron in their diet or an iron supplement.