Very few people are aware of the link between vitamin K and osteoporosis. However, over the last few years many scientific studies have shown that vitamin K deficiency could be a significant risk factor for the development of osteoporosis. Vitamin K is required for the production of a protein called osteocalcin. This protein is the main component in bone that binds calcium. Vitamin K deficiency or inadequate intake can reduce the synthesis of this protein and this can then contribute to a reduction of bone density.
In a recent 10-year study of more than 72,000 middle-aged and older nurses and former nurses, researchers found that women who consumed at least 109 micrograms of vitamin K per day had a 30% lower risk of hip fracture than those who consumed less. The foods that contributed the most to dietary vitamin K intakes in the women studied where iceberg lettuce, broccoli, cooked spinach, cabbage, raw spinach, romaine lettuce, Brussels sprouts, kale and other greens, along with oil and vinegar dressing.
Women who consumed lettuce one or more times per day had a 45% lower risk of hip fracture than women who consumed lettuce less than once per week.
Women who already have significantly reduced bone density may need to take up to 1mg of vitamin K daily, and this amount is available only from supplemental sources.
