There’s been a bevy of information this past few years on how nutritional supplements like vitamin D impact knee arthritis. However, less has been published on vitamin K. Now a large study shows that low vitamin K is associated with more knee arthritis progression.
What the heck is vitamin K? It’s a group of fat soluble vitamins that help in the creation of blood clotting proteins as well as help the proteins in bones bind calcium. I personally remember where to get vitamin by the fact that the “K” stands for “Kale”, the food that has the most vitamin K. In addition, other vitamin K foods are in that same family of veggies like spinach, collards, chard, broccoli, cabbage, asparagus, and lettuce. In addition, absorption of vitamin K is helped by fats and oils, so cooking these items or eating them with butter a vegetable oil will get more into your system. Finally, the normal bacteria in your colon also make a significant portion of your vitamin K needs.
The new study looked at 791 adults who had bilateral knee MRIs as part of another ongoing study. Vitamin K1 levels as well as dephosphorylated-uncarboxylated MGP ((dp)ucMGP) were measured. The latter is a protein that is predictive of vitamin K status, but in reverse so that higher levels are associated with less vitamin K. The patients were tracked for 3 years, specifically looking for progression of the knee arthritis as measured by cartilage and meniscus damage. Participants with a low vitamin K1 level (<0.2 nM) were more likely to have damage of cartilage and meniscus over three years. Higher ((dp)ucMGP) levels were also associated with more meniscus damage, bone spurs, bone marrow lesions, and bone cysts.
The upshot? Low vitamin K levels were associated with progression of arthritis in this study. Unlike other studies that have looked at a snapshot in time and measured levels, this study focused on whether lower levels were associated with more progression of arthritis over time, making it a more powerful study than prior studies that only looked at a snapshot of vitamin K and arthritis. However, will taking vitamin K or eating more green leafy veggies reduce your arthritis risk? That’s still open for debate as this recent review of the literature found. In the meantime, it certainly couldn’t hurt to get your levels measured or just make a concerted effort to eat more salads!