An additional note if you're taking NAC as a zinc ionophore instead, NAC and Glycine are precursors to the antioxidant Glutathione that your own body makes and those two with Magnesium are important in manufacturing collagen to repair joints. Magnesium Glycinate is also the most bioavailable form of Magnesium and you'll find some brands selling "GlyNAC" which is all three in a single pill for convenience.
An additional note if you're taking NAC as a zinc ionophore instead, NAC and Glycine are precursors to the antioxidant Glutathione that your own body makes and those two with Magnesium are important in manufacturing collagen to repair joints. Magnesium Glycinate is also the most bioavailable form of Magnesium and you'll find some brands selling "GlyNAC" which is all three in a single pill for convenience.