Sulforaphane is also a precursor of the antioxidant Glutathione, which is necessary to avoid oxidative stress from COVID-19. People prefer to take NAC to boost their Glutathione levels, but Sulforaphane will work, too, to a lesser degree.
It is also an NRF2 activator, which manages the antioxidant production of the immune system.
-PJ
-PJ