references
Office of Dietary Supplements: “Vitamin K Health Professional Fact Sheet”
Harvard T.H. Chan School of Public Health: “Vitamin K”
Oregon State University: “Vitamin K”
Blood: “Functional Study of the Vitamin K Cycle in Mammalian Cells”
U.S. National Library of Medicine: “Prothrombin Time Test and INR (PT/INR)”
Medicine: “Vitamin K Intake and the Risk of Fractures”
Current Medicinal Research: “The Role of Matrix Gla Protein (MGP) in Vascular Calcification”
U.S. National Library of Medicine: “Orlistat”
Merck Manuals: "Vitamin K Deficiency"
Food & Nutrition Research: "Vitamin K: food composition and dietary intakes"
Most people get plenty of vitamin K from the foods they eat.
Image Credit: Xsandra/E+/GettyImages
Image Credit: Xsandra/E+/GettyImages
- How Much You Need
- Foods
- Benefits
- Deficiency
- Drug Interactions and Risks
- Supplements
Age Male Female Pregnancy Lactation 0 to 6 months 2 mcg 2 mcg 7 to 12 months 2.5 mcg 2.5 mcg 1 to 2 years 30 mcg 30 mcg 4 to 8 years 55 mcg 55 mcg 9 to 13 years 60 mcg 60 mcg 14 to 18 years 75 mcg 75 mcg 75 mcg 75 mcg 19+ years 120 mcg 90 mcg 90 mcg 90 mcg
Source: National Institutes of Health
Source: National Institutes of Health
Leafy greens like kale are great sources of vitamin K, aka the "blood clotting vitamin."
Image Credit: Candice Bell/iStock/GettyImages
Image Credit: Candice Bell/iStock/GettyImages
Because vitamin K is a fat-soluble vitamin, it’s more readily absorbed by the body when consumed along with a source of fat. Go ahead and sauté your kale in a healthy glug of olive oil, drizzle avocado oil over your spinach salad or mash some soybeans into homemade guacamole. Also interesting: “Leaner cuts of animal foods contain less K2 [or menaquinone] than higher fat animal foods and full-fat dairy,” says Wendy Bazilian, DrPH, RD, a registered dietitian and author of the Eat Clean, Stay Lean series.
A severe vitamin K deficiency may cause symptoms related to increased bleeding, including nosebleeds or bleeding into the skin, causing bruising, according to Merck Manuals. Properly prescribed vitamin K supplements may help decrease bruising if you have a true vitamin K deficiency. However, vitamin K deficiency is rare, and if your bruising is caused by anything else, increased vitamin K intake is unlikely to help your condition. A few small studies have indicated that vitamin K creams may help with healing bruises, but more research needs to be done in this area.
A few small studies have indicated that vitamin K creams may help with healing bruises, but more research needs to be done in this area.
Newborns are given a vitamin K injection at birth to prevent deficiency.
Image Credit: Narongrit Sritana/iStock/GettyImages
Image Credit: Narongrit Sritana/iStock/GettyImages
“Vitamin K toxicity is unlikely and pretty rare,” Leah Kaufman, RD, a New York-based registered dietitian, tells LIVESTRONG.com. What’s more, the NIH states that no adverse health outcomes have been reported, either from dietary or supplemental vitamin K.
Most people don't need to take a vitamin K supplement.
Image Credit: Tero Vesalainen/iStock/GettyImages
Image Credit: Tero Vesalainen/iStock/GettyImages
Office of Dietary Supplements: “Vitamin K Health Professional Fact Sheet”
Harvard T.H. Chan School of Public Health: “Vitamin K”
Oregon State University: “Vitamin K”
Blood: “Functional Study of the Vitamin K Cycle in Mammalian Cells”
U.S. National Library of Medicine: “Prothrombin Time Test and INR (PT/INR)”
Medicine: “Vitamin K Intake and the Risk of Fractures”
Current Medicinal Research: “The Role of Matrix Gla Protein (MGP) in Vascular Calcification”
U.S. National Library of Medicine: “Orlistat”
Merck Manuals: "Vitamin K Deficiency"
Food & Nutrition Research: "Vitamin K: food composition and dietary intakes"
