Mamazon, I am 6ft1 also. Completely naturally so. Unusual yes, unnatural no, definately not!!
Incidentally, my parents investigated oestrogen treatment to limit my height, I had bone scans done etc, but in the end they decided to let me be tall. I am 6ft1, my sister is 6ft2.
Sorry, completely off topic I know, but the fact that someone stated Mamazon was unnaturally tall got my back up!
Will go now