Last week, I donated blood for the first time, which was a major milestone for me. I had been declared ineligible to donate twice before: first in the U.S. for spending time in Pakistan (a Malaria-endemic country) , and then in Dubai for having a nose piercing less than a year before trying to donate (despite that I was pierced with single use equipment).

Throughout my journey in pursuit of donation, a variety of people asked me why I wanted to donate? I didn’t really have an answer other than I thought it was the right thing to do. I decided to look into what shaped my thought process, and I found a list of things that tell me why donating blood is the right thing to do.

1. Twenty-five percent or more of us will require blood at least once in our lifetime.

That’s you. That’s me. And probably our families. By donating blood, we aren’t just helping some person we’ve never met. We’re probably helping our loved ones.

2. Not that many people are donating.

About 50 percent of the U.S. population are eligible to donate blood, but just 5 percent of eligible donors actually donate. Despite what many might think, blood centers don’t always have enough blood.

3. Everyone’s blood type is needed.

My blood type is AB+, which means I can receive blood from basically everyone, but I can only give to other AB+ people. That seems less useful and a little discouraging, but if my blood can go to other AB+ people, there’s more of the other types for everyone else.

Also, AB+ donors have universal AB plasma; if you can donate plasma, that’s also awesome!

4. There are no substitutes for blood.

It can be only be given by another human being.

5. Most of us have enough blood to donate.

On average, we have about two pints of blood for every 25 pounds of body weight. Plus, the body is always making new blood, and after a couple of months, we completely replenish the supply we have donated.

6. Your blood can save someone’s life.

Check out the World Health Organization’s visual materials for their 2016 World Blood Donor Day campaign! They show you a few people that were saved because of donation.