Royal Green Bone food complex Royal Green Bone food complex has been developed with one goal: the maintenance of normal bones. For this purpose, the 4 most important ingredients from nature have been brought together. The exclusive calcium and magnesium complex comes from a special red algae (algas calcareas), so not from stone (e.g. calcium carbonate), but from a pure vegetable source. This includes the most absorbable vitamin K2 (MK-7) and vitamin D3. added for optimal functioning in the body.