I'm not sure I completely understand. The zinc & selenium deficiency is causing your hair loss? zinc &selenium overdose will cause hair loss too. I'm assuming you took some suppliments and that should have returned your hair to normal. What does your doctor say? Genetics dont account for the zinc & selenium deficiency causing hair loss. Is it a coincidence that your grandmothers had hair loss?
Do you have PCOS? I do an my hair is coming out at an *alarming* rate. According to my doctor, if its hormonal hair loss, stimulating the scalp will increase the blood flow and hormones to the area. Doing so will make your hair fall out even quicker -so no topical rogaine type of thing. IMO I'd skip any herbal stimulant type of thing. Doing a 'no shampoo' shouldnt hurt. Apple cider rinse, baking soda massage. Also, once stimulated the cycle has already started and is pre determined. (I can ask for further clarification on that if you'd like)
So, for me I can do nothing until my hormones are under control or my hair will realllllly start to disappear. The whole PCOS/blood sugar/hormonal imbalance for me is a whole what came first, chicken or egg scenario. All the hormones are intertwined and feed off each other. Feel free to PM if you'd like.