How long after hair transplant, can I start taking zinc and multivitamin supplements? (photos)

My surgeon told me to start taking zinc and multivitamin after six months of your transplant. However on the other hand my friend was told to start taking it after a month as soon as the scabs are gone. Could you tell me the correct answer please as I don't wana delay taking the multivitamin and zinc supplement as they are very helpful for my hair growth? My current hair looks like this after 5 weeks of transplant, I have lost almost more than half of my hair... Many thanks, Kind regards, Mansoor