NOW Vitamin K-2 100 mcg provides Menaquinone-4 (MK-4) at a very accessible price point, making it popular as evidenced by its high review count. While MK-4 is a form of Vitamin K2, nutritionists and research suggest that for systemic effects on bone and arterial health, higher doses (often in milligrams) are typically needed, or the MK-7 form is preferred due to its longer half-life. At 100 mcg, this MK-4 dose offers minimal benefit for targeted goals. The addition of Alfalfa powder is largely irrelevant for the primary K2 benefits. Crucially, the absence of Vitamin D3 means it misses out on the essential synergy that optimizes K2's role in calcium metabolism for bones and arteries.