When healthy people without symptoms get a full-body MRI scan, about 1 in 3 people end up with some unexpected finding on the scan — and almost 6 out of 10 of those surprises don’t clearly mean anything medically important.

Using a full-body MRI scan on people who feel fine can sometimes find hidden health problems they didn’t know they had—and some of those problems might need a doctor’s attention.

When doctors scan healthy people’s whole bodies with MRI and find unexpected issues, most of those findings turn out to be important enough to check further—only about 1 in 10 are harmless.

When healthy people without symptoms get a full-body MRI scan, doctors often find weird little things that aren’t actually harmful—but those findings can lead to more tests and stress that might not be needed.

When people who feel fine get a full-body MRI scan, they often find weird little things that aren’t cancer—but those weird finds happen more often than actual cancers are discovered.

When doctors scan someone’s whole body for research, they sometimes find unexpected things — and more than half the time, they can’t tell if those things are harmless or dangerous without doing more tests.