somebody i work with told me that when you inject oil based gear in your delts, tris, or pecs that you increase the risk of gyno. he said oil is fine in the glutes or quads and water based is for upper level spot injecions. he said he was told this by a doctor who knows his way around the needle, and not novacaine. i'm just lookin for a little input, i only had one gyno problem and it fixed easily. i'm not in a rush for another one.