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How You Can Help

Frequently Asked Questions about Donating Blood and Platelets

  • Donating Blood

  • Certain blood types are in greater demand (and shorter supply) than others at different periods. However, donors of all blood types are needed and welcomed.

  • A "unit" of blood is collected during a donation. This is equivalent to about one pint of blood.

    Most adults have between 10 and 12 pints of blood in their bodies. Your body will replace the lost fluids within 24 hours, and will begin to replace the lost blood cells right away.

  • Most people say they only feel a slight pinch of the needle at the start of the donation. (Many people also report feeling great after donating because they know they've helped patients in need.)
    • Eat a nutritious and filling meal the day of your appointment (and get plenty of calcium).
    • Make sure you are well-hydrated. Try to drink six to eight 8-ounce glasses of water the day before and the day of your donation appointment.
    • Bring a valid photo ID with you to the appointment.
    • We encourage donors to drink plenty of good fluids (water and juices) after donating. This will help keep your body well-hydrated.
    • Eat well the day of your donation and don't hesitate to snack if you feel hungry.
  • As long as you are healthy and continue to meet the eligibility criteria, you can safely donate every 56 days.
  • Iron is an essential mineral in your body. There are two different types of iron – heme iron and nonheme iron. Lean meats and seafoods are the richest sources of heme iron, which is easily absorbed by the body. Nonheme iron, which is less easily absorbed by the body, can be found in nuts, beans, vegetables, and fortified grain products. Eating different combinations of foods help enhance the absorption of iron, specifically the harder to absorb nonheme iron. Vitamin C-rich foods, like citrus, eaten in combination with iron-rich foods, enhance the body’s absorption of iron.

  • Donating Platelets

  • If you are blood type AB, your platelets are especially valuable to certain patient populations. However, platelet donors of all blood types are always needed.
    • Eat a nutritious and filling meal on the day of your appointment (including plenty of calcium).
    • Make sure you are well-hydrated. Try to drink six to eight 8-ounce glasses of water the day before and the day of your donation.
    • Bring a valid photo ID with you to your appointment.
  • Most people say they only feel a slight pinch of the needle at the start of the donation. Because platelet donors get their oxygen-carrying red cells back, donors report feeling less tired than after giving blood. (Many people also report feeling great after donating because they know they've helped patients in need.)
    • We encourage donors to drink plenty of good fluids (water and juices) after donating. This will help keep your body well-hydrated.
    • Eat well the day of your donation and don't hesitate to snack if you feel hungry.
  • As long as you are healthy and continue to meet the eligibility criteria, you can safely donate every seven days. Many of our platelet donors schedule regular appointments every other week.
  • Iron is an essential mineral in your body. There are two different types of iron – heme iron and nonheme iron. Lean meats and seafoods are the richest sources of heme iron, which is easily absorbed by the body. Nonheme iron, which is less easily absorbed by the body, can be found in nuts, beans, vegetables, and fortified grain products. Eating different combinations of foods help enhance the absorption of iron, specifically the harder to absorb nonheme iron. Vitamin C-rich foods, like citrus, eaten in combination with iron-rich foods, enhance the body’s absorption of iron.
  • Thank you for being — or considering becoming — a donor.