maybe not ethnicity or demographicaly, but our genetics SHOULD determine our dosage...
if one responds easily to something with great success, due to their genetics, then that dose is appropriate...
some people can take more drugs than others for x amount of results...
however, there is no way to determine that unless you have experienced it, with that said, it is most wise to follow all the guidelines...
first, you should have a proper grasp of your nutrition, and what it takes to grow, maintain and cut properly...
etc. etc.
finally we start with the lower reccommended doses because we have no damn clue how we are going to react... we dont adjust during the cycle, we learn... then when we run another cycle we sit and evaluate everything...