When it comes to Vitamin C the more the merrier and I would go for 12gm. The worst what may happen is that it may give you the trots. But in order to avoid this start out at a lower dose an keep increasing it. As far as the NAC is concerned, it boost your resistance as it is a precursor to glutathione, protects and helps your lungs as well as your liver. There is plenty of material to rad about NAC all you have to do is Google for it. Amongst others it also helps people with COPD. Stay healthy and well, the best to you!
Many thanks!
12g is too much for me; awhile back, I had gradually increased up to 8g & it was bad...
Maybe 6g; I’m at 4g now.