some people are like that
i think it has a lot to do with how much total exposure one has had, and how long one has been exposed, and how well each individual gets rid of it, how much gets stored in the process.
that is what makes the problem so insidious for those who are devestated by it - there are those who can stand back and say looky here ma, mouthful of mercury and no prob!
flushing will only help with mercury effects, fillings or no. i feel better with each filling out of my mouth. i remember playing with elemental mercury as a child. had a jar of it. held it in my hand a lot. i think it really sensitized me to it. try explaining that to a doctor. they sent me to a shrink instead!
also, the inability of certain individuals to chelate mercury from the body is what is thought to account for the 1 in 100 children(males, females are 1 in 300) that develope autism from vaccinations. go figure!?