The FA has issued guidance aimed at reducing heading during practice for all Youth players as per below and the attached document

FA Heading Guidance - Issued February 2020 and to be applied with immediate effect :

Under 7's - Under 11's inclusive : Heading should not be introduced in training in these age groups
Under 12's : Heading remains low priority - One session per week maximum five headers per week
Under 13's : Heading remains low priority - One session per week maximum five headers per week
Under 14's - Under 16's inclusive : Heading remains low priority - One session per week maximum ten headers per week
Under 18's : Heading drills should be reduced as far as possible, taking into consideration the heading exposure in matches

FA Heading Guidance - Download / Open