A study published in the American Journal of Epidemiology (Volume 167, Issue 3; February 1, 2008; pages 313–320) examined the relationship between vitamin K status and inflammation. Vitamin K has been linked in prior research to reduced risk of cardiovascular disease and osteoporosis, and this observational study explored whether anti-inflammatory effects might help explain those associations.
The analysis used data from 1,381 participants in the Framingham Offspring Study. The average age of the subjects was 59 years. Vitamin K status was assessed using both dietary intake data and serum vitamin K levels.
Researchers evaluated 14 different inflammatory markers—blood-based indicators of chronic inflammation. Higher dietary intake and higher blood levels of vitamin K were consistently associated with lower levels of inflammation. The study also examined vitamin D status and found that higher vitamin D levels were associated with reduced oxidative stress; however, the anti-inflammatory effects of vitamin D were less consistent than those observed for vitamin K.
Vitamin K exists in two primary forms. Phylloquinone (vitamin K1) is found mainly in green leafy vegetables such as spinach and broccoli. Menaquinones (vitamin K2) are produced by intestinal bacteria and are also found in certain fermented foods and animal products.
