If it looks like a scam, it’s a scam. “Healthy immune system” is a clear giveaway. Don’t be fooled.
Yep, the golden rule.
I've tried many supplements which included NAC (my system wouldn't tolerate it), Nattokinese (does absolutely nothing), Selenium (again, my system couldn't tolerate it), and a few others. The only things I take these days are doctored recommended Vitamin D and Niacin. That's it.