Vitamin K2—is that even a bona fide vitamin? This is a legit question as K2 has been languishing in the nooks and crannies of scientific discoveries for too long. It’s not until very recently that this underrated vitamin received deserved public and medical attention.

The so-called sunshine vitamin is the cold season's hot topic pretty much everywhere in the media. We're warned of vitamin D deficiency and Seasonal Affective Disorder (or ‘the winter blues’).