Recent researches indicate that vitamin K is very important for the transportation of calcium from the blood to the bones.
Research also indicates that most people are deficient in vitamin K and especially those suffering from osteoporosis. Vitamin K is usually found in foods from animals but since animals are now mostly feed with grains (low in vitamin K) instead of grass (high in vitamin K), our meats, dairy products and eggs are now vitamin K deficient. Fortunately, green vegetables (rich in chlorophyll) are also rich in vitamin K.
Vitamin K is still fairly hard to come by in a supplement form but we can obtain a fair amount by ensuring we have a good intestinal flora (source of vitamin K).