When it comes to nutrients that help ensure good health, people remember vitamins A through E, but many forget about vitamin K. Named after the German word, "koagulation," vitamin K is a fat-soluble vitamin important to the process of blood clotting. This essential nutrient also helps build strong bones and contributes to heart health. Because certain bacteria in the intestines manufacture vitamin K, shortage is rare. However, infants and people with absorption issues are susceptible to vitamin K deficiency. Learn more about the different types of vitamin K and signs and symptoms of inadequate levels.
Types of Vitamin K
Vitamin K is available in three types:
Also called phylloquinone, vitamin K1 is a nutrient found in plants, particularly green vegetables. Vitamin K2, or menaquinone, is the type made by bacteria in the intestines, and vitamin K3, or menadione, is a synthetic form of vitamin K.
Symptoms of Vitamin K Deficiency
Problems with coagulation are among the most common symptoms of vitamin K deficiency. These include easy bruising, bleeding gums, nosebleeds, wounds that won't stop bleeding, blood in the urine, heavy menstruation, and vomiting blood.
Vitamin K Deficiency in Infants
Because they have very little intestinal bacteria, all infants are born with inadequate levels of vitamin K. While a mother's breast milk contains the vitamin, amounts are too small to provide protection. Research shows that a single vitamin K injection at birth helps prevent symptoms of deficiency until babies can make their own vitamin K.
Problems with Vitamin K Absorption
Certain health problems can impair the body's ability to absorb vitamin K. These include celiac disease, Crohn's disease, cystic fibrosis, gallbladder disease, or liver disease. Studies show that certain drugs like blood thinners and antibiotics can also affect levels of vitamin K in the body, as can heavy alcohol use.
Dietary Sources of Vitamin K
Foods that help prevent vitamin K deficiency include broccoli, kale, spinach, asparagus, dried basil, soybeans, olive oil, and dried prunes. While freezing can destroy vitamin K in foods, heating does not. Studies show that people whose bodies can’t absorb enough vitamin K can benefit from a multivitamin containing the nutrient, but in certain circumstances a vitamin K injection may be required.
Vitamin K is often called the "forgotten vitamin," yet it offers many health benefits to the body including the promotion of healthy coagulation, strong bones, and a vigorous heart. With the exception of infants, regular consumption of foods containing vitamin K can help prevent deficiency for most people. However, people with nutrient absorption problems or those on blood thinners should consult with a health care professional regarding vitamin K levels.