(CNN) Facebook is no longer just a place to connect with former high school buddies; the social media giant now wants to make it easier for you to connect with blood banks, too.

On Wednesday, Facebook launched a blood donation feature in the United States to help users find places to donate blood in their area and be notified when a nearby blood donation center may be in need.

The feature allows users to sign up to be blood donors in the "about" section of their profiles and then receive notifications from blood donation centers. The tool comes just in time for summer, a season when blood donations are typically low.

"In five US cities, we're going to put a notice right at the top of News Feed, asking people to register if they want to," Sheryl Sandberg, the chief operating officer of Facebook, told CNN Chief Medical Correspondent Dr. Sanjay Gupta in an exclusive interview on Tuesday.

Those cities are Chicago, New York, San Francisco, Baltimore and Washington, but the feature will roll out nationwide in the coming months, according to Facebook.

"Then, if there's a blood shortage in your city, our partners like the American Red Cross can notify you and give you an opportunity to donate," she said. "This is an opportunity for us, we think, to help people contribute to each other in a way that's really important."

'This could ... change the blood banking system'

More than 35 million people have signed up to be blood donors on Facebook in countries where the donation feature is available, according to the social media giant

JUST WATCHED Saving lives: The story of blood donations Replay More Videos ... MUST WATCH Saving lives: The story of blood donations 07:14

Now, "taking the results that Facebook has achieved in Brazil and India and Pakistan, we can actually, conceptually, could double the number of blood donors in the United States," Cliff Numark, senior vice president of the American Red Cross, told Gupta on Tuesday.

Each year, an estimated 6.8 million people in the United States donate blood, according to the American Red Cross

"This could really totally change the blood banking system in America," Numark said.

The blood donation feature hits close to home for Hema Budaraju, Facebook's health product lead, who has seen the dire need for blood firsthand.

"Seven years ago, my dad was diagnosed with a stage 4 cancer, and he was undergoing extensive chemo," Budaraju told Gupta on Tuesday.

JUST WATCHED SMS revolutionizing giving blood? Replay More Videos ... MUST WATCH SMS revolutionizing giving blood? 03:25

As part of that chemotherapy, her father lost a lot of blood and needed transfusions daily for more than a week.

"We needed to go and find the donors," Budaraju said. Many of those donors ended up being friends and relatives.

"Here in the United States, every two seconds, somebody needs blood," she said. "The good news is that people are always willing to help. If you ask them, they'll come by."

The US blood donation feature is Facebook's latest move to use its platform for public health efforts.

Where Facebook stands on anti-vax content

This year, a spotlight was turned on how Facebook and other social media platforms have made efforts to crack down on the spread of health-related misinformation online , particularly around vaccines.

JUST WATCHED Facebook to crack down on anti-vaccine misinformation Replay More Videos ... MUST WATCH Facebook to crack down on anti-vaccine misinformation 01:20

Facebook has "an obligation" to provide its users with safe and accurate health information, Sandberg said, especially while the United States is struggling with its biggest measles outbreak in nearly three decades.

Facebook announced in March that it was working to tackle vaccine misinformation on its platform by reducing the distribution of groups and pages that spread anti-vax content and rejecting ads that include misinformation about vaccines, among other strategies.

"It's taking us a while to ramp this and we're working with experts around the world, but we're very, very committed to getting this right," Sandberg said. "We are dramatically decreasing the distribution and working on far fewer people seeing it. In some of the instances, we are taking things down, as well."

Get CNN Health's weekly newsletter Sign up here to get The Results Are In with Dr. Sanjay Gupta every Tuesday from the CNN Health team.

Not all content will be taken down, however, and that's "because of our approach to misinformation: that when things are hate or things are violence, we take them down," Sandberg said.

"When things are false, we dramatically decrease it, and we show the other side of the story," she said. "That's because the debate has to happen. The way you can say something is false is, you have to be able to say, 'here's the true side of the story' -- and so we want that debate to happen so that people do get educated and understand that the science is settled."