Well, if we have a disintegration once every 0.3 milliseconds, then after 1.3 x 10^{20} atoms have thus disintegrated (which is half the number in the body), we would end up, I calculate, with a total elapsed time of 3.9 x 10^{16} seconds, i.e. 1.25 x 10^{9} years. That is "hotter" than I would have expected, indicating we are all surrounded by an aura of our own radioactivity. I am somewhat surprised we are still living.