At SPF 23 the sunscreen start to interfere with vitamin D.
Maybe it could be that their brains aren't fully developed and they are going through a lot of different hormones which makes things more intense emotionally.
At least three a day because one for breakfast one for lunch and one for dinner
according to hairlossstressactions.com
"Yes, stress and hair loss can be related. Three types of hair loss that can be associated with high stress levels are: Telogen effluvium. In telogen effluvium (TEL-o-jun uh-FLOO-vee-um), significant stress pushes large numbers of hair follicles into a resting phase."