Vitamin K is a term which covers chemically related compounds known as naphthoquinones. These compounds include phylloquinone (vitamin K 1) which is synthesized by plants, menaquinone (K2) which is synthesized by bacteria in the gut and menadione (K3) which is the manmade form that is usually given as an injection.
Though vitamin K is known for its role in helping blood clot, it is also vital for bone health. According to the University of Maryland Medical Center the human body needs vitamin K to utilize calcium for bone mineralization or the bone building process. Low K levels are therefore associated with poor bone mineralization, which results in weak bones that break easily.
The American Journal for Clinical Nutrition published a study which showed that a low intake of vitamin K from the diet was associated with a low bone mineral density (BMD) in women. This low BMD increases the risk of bones fracturing.
Several studies have proven this correlation between low K levels and bone fractures. The Harvard School of Public Health reports the findings of one study in which women who received 110 or more micrograms of vitamin K each day were found to be 30 percent less likely to develop hip fractures of the hip than those who took less. In this Framingham Heart Study, a high dietary intake of vitamin K was also shown to increase bone mineral density in women and reduce the risk of hip fractures in both men and women.
Harvard also states that eating one serving of green leafy vegetables like lettuce reduced the risk of hip fractures by 50 percent in women who ate them daily when compared to those who ate one serving each week.
According to Dr Weil, other foods that contain vitamin K include parsley, broccoli, cauliflower, Brussels sprouts, liver and wheat bran. Fermented soy products like natto and miso together with fermented dairy products like cheese and yogurt are other good sources of vitamin K.
Written by: Marian Kim, FizzNiche Staff Writer