I once read a study during the height of covid about this[1], which is why I loaded up on Metform. Was lucky enough not to get covid in the meanwhile (or didn't notice), but better safe than sorry.[2]
Metformin is also popular in anti-aging circles due to its ability to modulate key cellular aging pathways. It activates AMPK and reduces mTORC1, enhances autophagy, reduces inflammation, and improves mitochondrial function, with studies showing promising, though not yet definitive, effects on increasing healthspan.