I believe this is only considered to be "the most important" by a certain proportion of the nutrition/health field, and is not the prevailing view/position. Not that the prevailing view is necessarily correct, but I'd urge
@DevGuy to look into all sides of this topic before making any decisions.
Fortunately, it seems one doesn't have to go all-in on either 'black' or 'red', as for most, it seems quite possible to achieve numbers within given/expected ranges regardless of diet choice.