Not yet investigated
What we have so far
Eumelanin and pheomelanin, from the same amino acid. Redheads make the second kind, which offers little protection and may generate damage in the dark, without any sun at all.
This star is on the map because the show intends to take the question apart properly — the trials, how it is actually tested, whether the thing sold is the thing studied. That work is not done yet, and nothing here should be read as a conclusion. When the investigation is published it will appear on this page.