> is like 80% of the work for being healthy

I would suspect you're a man under 60.

I don't think your statement applies to the elderly (e.g. my mum needing D and Calcium for osteoporosis).

And I've seen many active healthy female friends under 60 actually need suppliments (I'm ignoring the stereotypical yoga worried well): plus pregnancy or health issues have an impact too.

But maybe I'm a victim of sampling bias since the men I know seem much less likely to see a doctor.