Vitamin K is Made by the Body:
Vitamin K is different than other vitamins because it is actually made inside the body by "good" bacteria within the colon. About 80% of vitamin K needed is made in this way. The other 20% must come from food sources. If the "good" bacteria in the intestine is wiped out by antibiotics or affected by diarrhea, vitamin K production may be decreased. Vitamin K can be toxic in large does, and supplements should be used with care. Those taking the prescription drug Coumadin (Warfarin sodium) should not take vitamin K from supplements or food sources.
Who May Lack Vitamin K:
People with IBD, especially Crohn's disease, may have low levels of vitamin K due to a low dietary intake as well as poor absorption of vitamin K by the small intestine. Many of the foods that contain vitamin K are green, leafy vegetables, which people with IBD may avoid during a flare-up. This deficiency, along with a vitamin D deficiency, may contribute to the bone loss that is found in people with IBD.
Food Sources of Vitamin K:
Vitamin K is found in various foods including:
- Brussels sprouts
- Swiss chard
- Turnip greens
Duggan P, O'Brien M, Kiely M, McCarthy J, Shanahan F, Cashman KD. "Vitamin K status in patients with Crohn's disease and relationship to bone turnover." Am J Gastroenterol 2004 Nov; 99:2178-2185. 24 Sept 2009.
Kuwabara A, Tanaka K, Tsugawa N, et al. "High prevalence of vitamin K and D deficiency and decreased BMD in inflammatory bowel disease." Osteoporos Int 2009 Jun; 20:935-942. 24 Sept 2009.
National Institutes of Health. "Important information to know when you are taking: Coumadin and Vitamin K." Warren Grant Magnuson Clinical Center, National Institutes of Health Drug-Nutrient Interaction Task Force Dec 2003. 24 Sept 2009.
Natural Standard Research Collaboration. "Vitamin K." MedLine Plus 24 Sept 2009.