"We know that copper is used by the body to produce melanin, which is the dark pigment which colors the skin and protects against sun damage. PABA seems to be involved in this metabolism and this is the reason that many sunscreens contain PABA. My present theory is that sunshine on a person who is deficient in copper and/or PABA will result in an increase in those deficiencies and therefore may become more likely to get hyperT. However, sunshine on a person who is getting an adequate amount of copper and PABA may be very beneficial in helping the person recover from hyperT. This is just my theory, but if this is true then we could expect that persons who become more sensitive to the sun and who burn more easily may be copper deficient and therefore likely to develop hyperT."