Doc’s Original Vitamin D + K - 5000IU provides a 5000IU dose of vitamin D3, along with bioavailable vitamin K1 (Phytonadione) and Vitamin K (K2 as Menaquinone-7). • Highly Absorbable K - This formula provides the most absorbable, highly bioavailable form of vitamin K1. K2 as MK-7 is a product of fermentation which metabolizes slowly through