Here is the issue with supplements regarding hair loss:
Yes, we lose our hair because our hair follicles are not getting the vitamins/minerals/oxygen/nutrients that they need.
But this has literally nothing to do with the amount of vitamins or minerals a normal and healthy individual consumes on an average or even poor diet.
The problem is that those vitamins and nutrients that we consume and ingest through our diets are not making their way to the hair follicle because they are being stopped.
They are being stopped because of a blood flow restriction just like the heart muscle is when it experiences a myocardial infarction aka "heart attack."
So, you can take vitamins and "hair loss" supplements and biotin by the hand full and it will not make a bit of difference because they are not getting where they need to go to have any benefit.