that is a matter of great debate!
among other ideas, i do enjoy one very simple adage:
1. eat food (ie not processed pseudo-foods)
2. not too much
3. mostly plants
it doesn't go quite as far as it needs to re 'well rounded' or 'balanced' but, a good start.
odd sx? no dx? check w/ dietitian
DRI=MINIMUM eg bit.ly/1vgQclQ
99% don't meet these. meds/lifestyle can affect levels
status can be low in ms & other cond'ns
'but my results are normal'. typical panels don't test all
deficits occur in 'normal' range