"Whey protein contains nothing which causes hair loss. But, what you have to remember is, protein (any protein) coupled with weight training increases testosterone, which increases DHT, which in individuals cursed with balding, will make them balder – if they aren’t taking a DHT blocker such as Propecia.
If you are training and eating for muscle, it’s inevitable your testosterone will increase, and if you have the baldness genes, your hair loss will increase. You then have a decision to make – do you stop training, have a Mr. Average body and just slowly watch your hair fall out over a longer time period… or do you continue training, build a great body (and enjoy doing so) and maybe run the risk of losing hair quicker due to higher DHT levels? That’s your choice. If you’re going bald – you’re going to go bald anyway, sooner or later. Why agonize over it?
Also, I’m no doctor, but my logic is this: Get an appointment with your doctor and get on Propecia."
So the answer seems to be that there IS an effect. But I imagine it differs from person to person, as our biochemical makeups are all really varied. It's kind of impossible to answer whether or not DHT is reduction "cancelled out"--but it's certainly affected.