Do vitamin D3 and vitamin K2 need to be taken together?

No, vitamin D3 and vitamin K2 do not necessarily have to be taken together or at the same time. Both vitamins fulfil distinct functions: vitamin D contributes to the normal absorption and utilisation of calcium, as well as to the maintenance of normal bones. Vitamin K also contributes to the maintenance of normal bones and to normal blood clotting. As both are fat-soluble, it is recommended that they be taken with a meal containing some fat.