Facebook is now going to start reminding you when to get a medical checkup.

The company is rolling out a tool to remind its users in the U.S., based on demographic factors such as age and gender, to get a screening or health test.

The company is making this move, according to Freddy Abnousi, a cardiologist who runs Facebook's health efforts, because research from the Centers for Disease Control and Prevention and other research groups has shown that millions of people don't take evidence-based preventive steps to take care of their health. Abnousi shared the details of the initiative on Monday.

Facebook's new tool, called Preventive Health, is searchable via the mobile app. Users can find out which checkups, such as mammograms or cholesterol tests, are recommended for them. Facebook will also proactively nudge its users to get flu shots at the time of year when they're most likely to work, as well as find nearby locations such as grocery stores and pharmacies where they're available.

The company does not appear to have a way to check whether a user has already gotten a flu shot, risking redundant reminders. But avoiding this would require deeper integration with the health-care system, including patient medical records, and Facebook has previously shied away from that sort of integration in light of privacy fears.

The company is working with several partners in the public health world on the initiative, including the American College of Cardiology and the American Heart Association. "We've contributed our content and resources to the Facebook Preventive Health to empower Americans to take the first step to know about and take action to lower blood pressure, blood sugar and cholesterol," said Eduardo Sanchez, chief medical officer for prevention at the American Heart Association, in a statement.

"New tools like this will empower users with instant access to information and resources they need to become a flu fighter in their own communities," said Nancy Messonnier of the CDC, also in a statement.

The company said that over time it will add more organizations and spread to more countries.

The move isn't Facebook's first foray into health-related initiatives. The company has also developed tools to encourage people to give blood when there are shortages and promoted organ donations by asking users to share their status.

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