As for vitamin D, it's an important nutrient vital to many processes, and can be obtained by simply getting sensible sun exposure daily. (articles.mercola.com)
While you can get some vitamin D in foods like salmon, egg yolks, and mushrooms, your best solution for optimizing your levels is through sensible sun exposure. (eluxemagazine.com)
The trio of fat - soluble vitamins A, D and K2 (Price's x-factor) are best derived from nourishing foods where they occur in natural balance, along with sensible sun exposure. (westonaprice.org)