If you have dark skin, you still need sunscreen. The melanin in your skin will offer some protection from UVB rays, but it’s basically an SPF 2 for even the darkest skin tones. It does nothing to protect you from UVA rays or free radicals.

Along the same lines, base tans are just skin damage, they don’t protect you from anything except a tiny bit of UVB protection, but you had to damage your skin to get that so it’s pointless. — King