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Quick Dose: What Should I Eat Before Donating Blood?

Donating blood is an extremely rewarding experience that has the opportunity to save up to three lives with just one donation of one pint of blood. People often feel dizzy or weak after giving blood. Don’t let this prevent you from making a difference. With proper nutrition and hydration beforehand, you’ll avoid some of these uneasy feelings.

Since your body is made mostly of water, it’s important to stay hydrated before (and after) giving blood. A loss of fluids can lead to a drop in your blood pressure, which explains why some may feel dizziness. Be sure to drink at least two cups before you donate. You’ll also feel better if you have something in your stomach, which also stabilizes your blood pressure.

Eat foods that are rich with:

  • Iron. The removal of red blood cells also depletes iron stores from your body and can take about eight weeks to replace. If you don’t have enough iron stored away prior to giving blood, you could become anemic, which can make you feel tired and weak. Iron-rich foods include red meat, eggs, poultry, fish and leafy green vegetables.
  • Vitamin C. In contrast, vitamin C helps your body absorb more iron which will help your body replenish itself and avoid iron deficiency. Reach for citrus fruits, pineapple, mango or brussel sprouts.
  • Low fat foods. Fatty foods increase the amount of lipids in your blood. A blood sample high in lipids cannot be tested for infections that could cause harm to the recipient.

After you have donated blood, light refreshments are usually provided to help assist in replenishing the nutrients you’ve lost. It’s important to eat something, as your body needs to regain energy to rebuild lost cells. You should also avoid too much caffeine, as it can lead to dehydration and exhaustion. Continue to stay hydrated and avoid alcohol for at least 24 hours.

Tiffany Chang, MD, Medical Director of HealthLab, Pathology