Suppose you’re on Facebook or Instagram, and Meta has determined you may be interested in cancer treatments. In that case, you may have seen an ad for a dangerous cancer treatment, or one of the 20 or so others recently running from the CHIPSA hospital in Mexico near the US border, all of which are publicly listed in Meta’s Ad Library. They are part of a pattern on Facebook of ads that make misleading or false health claims targeted at cancer patients.

Gadget firms — starting with Apple and now Fitbit, which Google owns — are selling wearable devices that check heartbeat rhythms and alert users when something is out of sync, according to KHN.com. Although the gadgets are a technical achievement, some cardiologists say the information the devices produce isn’t always helpful. Notifications from the devices aren’t definitive diagnoses.

Routine cancer screening is essential to detect cancers early when it is most curable. The consequence of millions of people missing cancer screenings because of the COVID pandemic is a delay in detecting cancer, which results in cancer progressing to a more advanced stage. According to a study published in JAMA Oncology, a publication of the American Medical Association, nearly 22 million cancer screenings in the U.S. failed to happen because of the COVID-19 pandemic.