More support for vitamin K's protection from osteoarthritis
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.
"For the knee, only the PR for osteophytes [outgrowths on the bone associated with arthritis] and the adjusted mean number of knee joints with osteophytes decreased significantly with increasing plasma phylloquinone levels," she said.
The researchers concluded that their data support the link between vitamin K status and the risk of osteoarthritis, a disease that effects about seven million people in the UK alone are reported to have long-term health problems associated with arthritis. Around 206m working days were lost in the UK in 1999-2000, equal to £18bn (€26bn) of lost productivity.
Further study is clearly need to establish if the relationship is causal, particularly clinical trials - and indeed, some are already underway.
According to Controlled Clinical Trials, there are 12 registered clinical trials at various stages of completion being conducted worldwide using vitamin K. Six are concerned with bone health, while a further four are associated with the role of the vitamin in blood clotting.
