> We acknowledge several major limitations of this study. First, it is not possible to differentiate between active sun exposure habits and a healthy lifestyle, and secondly, the results are of an observational nature; therefore, a causal link cannot be proven.
All studies investigate correlation and that’s okay. Though this discussion overshadows that study’s actual problems.
I wager it’s only on HN because its title is an excuse for everyone to hone their hobby horse opinion on sun exposure.
Which makes me think that the title about "avoidance of sun exposure" is misleading, even if not deliberately so. "Avoidance" in the general lexicon usually means conscious choices to deliberately not expose yourself to something. Is someone who is, say, obese and bedridden "avoiding" sun exposure?
Why call it anything else. I mean it's like me writing a long paper proving that thermodynamics is flawed and then ending the paper with some acknowledgement that one of the key arguments has a logical flaw which renders the whole proof incorrect. So then the whole paper is worthless.