I guess all the grandmas on the beach that look like they have a leather hide for a skin didn't get the memo that the sun doesn't cause damage after all.
In all seriousness: don't listen to OP, use sunscreen whenever possible.
It depends on what you use for sunscreen. A lot of sunscreens have aluminum in them and there are many that have it but it is not listed as an ingredient. Zinc oxide sunscreen is a much safer sunscreen.