James R. Copland, CityJournal:

Millions of Americans own an Apple Watch, which commands roughly a 50 percent share of the smartwatch market. Among its many features, the Apple Watch can take your pulse. It also contains hardware to measure your blood-oxygen levels, and it has been doing so since the watch was released—but the hardware is not operable by the watch’s wearer, who thus cannot obtain the results. Under current FDA regulation, the function is disabled.

The article argues against federal regulation, and FDA overreach. That aside, what’s really interesting to me is the COVID-19 tie-in.

From this New York Times op-ed by longtime emergency doctor Richard Levitan:

We are just beginning to recognize that Covid pneumonia initially causes a form of oxygen deprivation we call “silent hypoxia” — “silent” because of its insidious, hard-to-detect nature.

And:

When Covid pneumonia first strikes, patients don’t feel short of breath, even as their oxygen levels fall. And by the time they do, they have alarmingly low oxygen levels and moderate-to-severe pneumonia (as seen on chest X-rays). Normal oxygen saturation for most persons at sea level is 94 to 100 percent; Covid pneumonia patients I saw had oxygen saturations as low as 50 percent.

And this is exactly what the Apple Watch’s built-in (but disabled) plethysmograph could prevent. If it doesn’t work, then no argument here. But if it works and the FDA’s testing would push off approval until, say, next year, this might be a time for an emergency exception. Lives are at stake.