MPB is related to genetics & few other problems. How many of weight lifters or bodybuilders do you see have hairs. Most professionals in this field have bald head. Although i am not a doctor but excess protein or hwey protein available in market are synthesized from chemicals which affect the hair follicles. DHT
is the main culprit. Saw palmetto is good to control DHT formation but results are not very good. You can consult a dermatologist
for this. Soy products are good to counter DHT related problems.
Further you can control hair loss by taking minoxidil