The research evidence is out there if you care to look for it, MOnica.
It does, of course, depend on the quality of the masks. The blue surgical masks which many people used were far less effective than the higher spec. N95 or FFP3, but even so, provided something of a double barrier to the virus particles. They were, of course, only designed to stop droplets, not aerosols.
I understand that Asians also wear masks when they have a respiratory illness in order to lessen the chances of infecting others.
What did you you think you would have by your current age that you don't?


