[10] Perhaps the most interesting and potent[editorializing] effect insulin-like growth factor 1 (IGF) has on the human body is its ability to cause hyperplasia, which is an actual splitting of cells.

[12] With IGF use, one is able to cause hyperplasia which actually increases the number of muscle cells present in the tissue.

[15] This differs from neoplasia (the process underlying cancer and benign tumors), in which genetically abnormal cells manage to proliferate in a non-physiological manner which is unresponsive to normal stimuli.

[16] That being said, the effects caused by pathologic hyperplasia can provide a suitable foundation from which neoplastic cells may develop.

Pathologic hyperplasia in these tissues may occur due to infection, physiological stress or trauma, or abnormal levels of particular hormones, such as estrogen, ACTH, or cortisol.