Does an increase in DHT cause hair shedding or does it just cause miniaturization for those who are prone? I understand its normal to loose about 100 hairs a day, but does the DHT increase the shedding to abnormally high levels including hairs that are not miniaturized already?
The process of genetic balding is produced by DHT (Dihydrotestosterone). If there was no DHT, balding would not occur. The way to prove this is to remove the testicles. If genetic balding had not already started, it would certainly not start after removing the testicles. This has been shown classically when one of two identical twins had his testicles removed. The balding occurred only in the twin with testicles.
There are two ways in which balding occurs. You could go from normal thickness hair to miniaturized hair with progressive miniaturization as the hair shaft loses more and more of its thickness over time. Alternatively, the hair can go into its normal sleep cycle and never come out of it. You might look at this second way as normal thickness hair falling out.