Hi Bex. Yes, np I tend to forget to look sometimes at all threads too, because I visit many other forums as well (good execuse, yeah:))

But yes, NAC has some downsides too, it's not ideal in all respects to raise glutathione (even though many appear to recommend it) and I haven't tried it myself. Cysteine in itself is also slightly toxic when in bloodstream (and so is also NAC), and may cause side-effects, especially in larger doses (which is what you still need). Whey protein on the other hand is a good choice, if you don't have an allergy to whey.

Regarding the chest pain, hard to say, I've also had it sometimes, and especially when I chelate. If you have a problem with your lungs and chest pain, it could be pleurisy (pleuritis). It is an inflammation, and causes chest pain and shortness of breath. It causes the outside layer around your lungs to fill with too much fluid, and you can get a fever, and this layer may have to be punctured to get it out. I know something about this, because my father ended up in hospital because of this, not so long time ago, where he also backfired from antibiotics. He still survived the incident, but only barely. One possible cause is a viral infection, and pleurisy has been described as a symptom of mercury poisoning. It is not a serious condition usually, but for those with a poor immune system it could lead to something worse of course (like fever).