According to the American Red Cross, someone in the United States needs a blood transfusion every two seconds. There’s a significant need for blood — and blood donations are always needed to keep hospitals supplied with enough.
Whether you’ve been donating blood for a long time or are considering making your first blood donation, you may have questions about how the process works. We answered a few common questions below.
Is donating blood safe?
Blood donation is very safe. When you donate blood, a new, sterile needle is used to draw the blood from your arm.
The entire process takes about 30 minutes if you’re donating whole blood, although it is longer if you donate platelets, plasma or other specific blood cells. During this time and for a short time afterward, you’ll be carefully observed by medical professionals.
Need another reason to donate? Donating blood is not only safe, but it also benefits your health by revealing any potential hidden health problems.
How much blood is taken?
Approximately one pint of blood is taken during a blood donation. For comparison, most adults have 8-12 pints of blood in their body.
The body replenishes the plasma, which is the liquid portion of blood, within 24 hours after donation. It takes about four to six weeks for the body to fully replenish its red blood cells, which is why you need to wait eight weeks between donations.
Can I donate blood if I have a tattoo?
Yes, as long as you had the tattoo applied in a state-regulated facility using sterile needles and fresh ink, and the site has healed. This usually is about two weeks after the procedure.
If you had a tattoo done in a state that doesn’t regulate tattoo facilities, the American Red Cross requires that you wait for at least three months before donating blood. This requirement is related to the potential for spreading hepatitis.
You can also donate blood if you have had a piercing done, as long as single-use equipment was used. If there’s any question about that, wait for at least three months before donating.
Can I donate if I’m pregnant?
You aren’t eligible to donate blood during pregnancy. The American Red Cross requires that you wait at least six weeks after giving birth before donating blood.
Donating blood during pregnancy could be unsafe for both you and your baby. It can cause problems such as iron-deficiency anemia, which can increase the risk of pre-term delivery.
What should I not do before donating blood?
Before donating blood, you’ll want to take the best possible care of your body. Drink extra water a day or two before your appointment and eat a healthy meal beforehand.
What shouldn’t you do? When choosing what to eat before donating blood, skip fatty foods and choose options that contain protein and healthy carbs. It may also be helpful to choose iron-rich foods , such as chicken, beans and spinach, to help increase your body’s supply of iron.
Don’t skimp on sleep, either. Aim to get at least seven hours of sleep the night before donating blood. You also should avoid smoking and drinking alcohol. Smoking impairs the blood’s ability to carry oxygen, while alcohol can cause you to become dehydrated.
One last tip? Reschedule if you’re feeling sick. You shouldn’t donate blood if you have a fever or a wet cough, so wait until you’re feeling better. If you’re prescribed an antibiotic for your illness, wait until you’ve finished taking it before donating.
Have other questions? You can find the answers to other frequently asked questions on our Give Blood page !
Donate Blood at University Health
You can save lives here in our community by donating blood. As a Level I trauma center, University Health is the largest blood transfuser in the greater San Antonio area.
The need for blood is great — and your donation can make a difference.
Learn about where and how to donate blood at University Health . You can even schedule an appointment to donate blood at a time that works best for you.
