I think red meat is a good example. We have evolved to handle consuming it, there are benefits to consuming it and negatives effects but the proportions you eat it in affect the relevance of those different consequences. Healthy amounts of red meat would be offset by a small, practically irrelevant increased risk of cancers, gastrointestinal problem etc. Going full Jordan Peterson goombah and eating nothing but meat is probably going to lead to pretty chronic diarrhoea and a significantly elevated risk of cancer.

Tanning easily is normal for many many people and only becomes a problem if you either abuse it, which many do or have some predisposition towards skin cancers but saying tannins unattractive because "ITS DAMAGE LITERALLY DAMAGE" is some weirdo shit