[leggomuhgreggo]

What's controversial here? The benefits of Vitamin D is pretty well established

( it's a "vital mineral" after all.)

I read the summary and didn't see anything very adventurous.

[fylham]

Sure, it is vital, but he claims that lack of vitamin D underlies nearly all diseases of modernity, which isn’t well-established. Meanwhile he was making money selling vitamin D and not disclosing it, which makes his motivation seem suspect. It’s very easy for bias to obliterate the validity of research.