welcome to "healthcare magic forum"
look any vitamin, iron tab will help u to increase the levels in your body , surely low nutrition levels is one of the causes for the hair loss but in your condition are you sure to mark this reason for the hair fall
because you have also stated your beard area with less hair growth , will suggest u to consult a homoeopath who will asses the cause for all these reasons and prescribe you medicines which are very safe , effective and natural .
these will treat the root cause and u can find regrowth as well.
do continue a good , healthy diet always .
consult a homoeopath at d earliest.
wish u good health alwyas ! godbless!