Interesting news. I'll be interested to see what happens with your results.
Its hard to say for me whether its eating too much meat, dampness as cm says or a pathogen of some sort creating weakened immunity. Again I'll say I feel absolutely great, aside from a little bit of fatigue after meals some times. Overall energy is good, mood is good, in great health, eating completely organic, sleeping on time and rising early.
Since I've been doing the mouth wash and rinsing my mouth after meals my tongue coating has improved tremendously. However, I'm sure if I stop the mouth wash it will probably return. Although I didn't use the tongue cleaner today, just the wash and it looks pretty good.