More support for vitamin K's protection from osteoarthritis
By Stephen Daniells

12/04/2006- Higher intake of vitamin K, found naturally in cabbage, spinach, cauliflower, and other green leafy vegetables, could reduce the risk of osteoarthritic knee problems by 40 per cent, says new research. Other epidemiological studies have shown a correlation between high vitamin K intake and a lower incidence of osteoporosis. One European study also showed that a combination of vitamins K and D, along with calcium, could have a significant effect on improving bone strength.

The new study, published in the journal Arthritis and Rheumatism (Vol. 54, pp. 1255-1261), is another observational study of the benefits of the fat-soluble vitamin on bone health. Tuhina Neogi from the Boston University School of Medicine led the population-based prospective cohort. Although deficiency of the vitamin is rare, the researchers found a difference between the highest and lowest intakes, and the respective risks of hand and knee osteoarthritis among 672 participants, with an average age of 66.

The researchers measured blood levels of phylloquinone, the main form of the vitamin, and correlated this with the occurrence of hand and knee osteoarthritis, recorded by radiographs."As plasma phylloquinone levels rose, the prevalence ration (PR) for hand osteoarthritis decreased from 1.0 to 0.7," reported Neogi.