How Do You Know If You Have a Vitamin K Deficiency?

Signs of Vitamin K Deficiency

How Vitamin K Affects the Body

Vitamin K is a crucial vitamin that plays a vital role in the body. It is responsible for making blood-clotting factors in the liver that help stop excessive bleeding. A blood clot is a "clump" of proteins and platelets (disc-shaped cell fragments) that plug wounds within the body to stop blood loss. Vitamin K is also needed to form osteocalcin, a key component of bone tissue that, when lacking, may weaken bone structure.

Who Is at Risk?

Vitamin K is a fat-soluble vitamin, meaning it’s absorbed in the gut when you eat foods containing fat or oil. Vitamin K deficiency may develop in severe or prolonged cases of starvation or critically ill people with malnutrition. People with diseases associated with impaired fat absorption in the gut, such as celiac disease, Crohn’s disease, or cystic fibrosis, are also at risk.

Testing

Prothrombin time (PT)/international normalized ratio (INR) is the primary blood test to diagnose vitamin K deficiency. This simple blood test measures the time it takes for blood to clot, and with vitamin K deficiency, both the PT and INR are elevated. Vitamin K-dependent factors (VII, IX, X) may also be checked to help confirm a diagnosis of vitamin K deficiency or rule out other bleeding/clotting disorders.

Management and Treatment Options

Treating vitamin K deficiency involves administering vitamin K, although the cause must be considered. In adults with vitamin K deficiency, a dose of synthetic vitamin K (phytonadione) is given by mouth unless the cause is due to gut malabsorption. In such cases, vitamin K is administered as a shot into the fatty tissue (subcutaneously).

Dietary Intake

Evidence suggests that most healthy individuals in the United States obtain enough vitamin K in their diets. Even in those with a lower-than-recommended intake, reported symptoms like bleeding are rare. Experts suggest an adequate vitamin K intake for males is 120 micrograms (mcg) and 90 mcg for females.

Summary

Vitamin K is found in several food sources and is produced naturally by bacteria in the gut. A vitamin K deficiency is rare in healthy individuals. Excessive bleeding is the primary sign of vitamin K deficiency. People at risk for vitamin K deficiency are those with underlying health conditions that impair the gut’s absorption of vitamin K or who take certain vitamin K-interfering medications, such as antibiotics or warfarin. Newborns are also prone to vitamin K deficiency due to a low transfer of vitamin K between the pregnant person and the fetus.

Frequently Asked Questions

Q: What are the symptoms of vitamin K deficiency?
A: Symptoms of vitamin K deficiency include easy bruising and excessive bleeding.

Q: Who is at risk for vitamin K deficiency?
A: People with underlying health conditions that impair the gut’s absorption of vitamin K, such as celiac disease, Crohn’s disease, or cystic fibrosis, are at risk. Additionally, people taking certain vitamin K-interfering medications, such as antibiotics or warfarin, are also at risk.

Q: How is vitamin K deficiency treated?
A: Vitamin K deficiency is treated by administering vitamin K, either by mouth, as a shot, or intravenously, depending on the clinical scenario.

Q: How much vitamin K do I need each day?
A: The recommended daily intake of vitamin K varies by age and sex, with experts suggesting 120 micrograms (mcg) for males and 90 mcg for females.