According to the Stanford Blood Center website, "Only 39% of the general population are eligible to donate, but fewer than 5% of those eligible actually donate."
I donated blood today for the first time. It took 7 minutes and 45 seconds to extract a pint of blood from my left arm. In the beginning, I didn't clench my first, but I think if I did, my extraction time would have been shorter.
After the extraction, I felt a little light headed, but felt fine after eating In-N-Out. Around 5 pm, I started to feel kind of tired and crawled into bed. In the next hour, I felt progressively more sleepy and stayed in bed to rest. I'm not sure if the fatigue was due to my blood donation or perhaps less energy in general due to my lack of exercise in the past week. It lasted until around 9pm, when I decided to eat an apple and drink water. My arm is still sore but I feel much better than I did just a few hours ago.
I don't know if I'll be a regular donor (every 56 days), but I encourage everyone to donate at least once a year to "pay it forward."
http://www.redcrossblood.org/