Vitamin K Deficiency: A Look at the Disease Caused by Lack of Vitamin K

November 18, 2025 •

4 min read

According to the CDC, vitamin K deficiency bleeding (VKDB) is a serious condition that affects some newborn babies and is completely preventable with a simple vitamin K shot at birth. A deficiency disease caused due to lack of vitamin K is primarily a bleeding disorder that can manifest differently across various age groups. While rare in healthy adults, it remains a significant concern for newborns and individuals with certain health conditions.

Quick Summary

Vitamin K deficiency causes hemorrhagic disorders by impairing blood clotting. In newborns, this is known as vitamin K deficiency bleeding (VKDB), while in adults, it can lead to easy bruising and excessive bleeding, particularly if underlying conditions affect absorption.

Key Points

Bleeding Disorders: The main deficiency disease from a lack of vitamin K is a bleeding disorder, most notably Vitamin K Deficiency Bleeding (VKDB) in infants.
Critical Clotting Factor: Vitamin K is essential for activating the blood-clotting proteins synthesized in the liver; without it, blood cannot clot properly.
Newborn Risk: Newborns are especially susceptible to vitamin K deficiency due to low levels at birth, which is why a prophylactic injection is standard procedure.
Underlying Causes in Adults: While rare in healthy adults, a deficiency can be caused by malabsorption issues, chronic diseases like liver disease, or certain medications like anticoagulants and antibiotics.
Bone Health Implications: A long-term deficiency can also negatively affect bone health by impacting the protein osteocalcin, which is crucial for bone mineralization.
Treatment is Effective: The condition is treatable with vitamin K supplementation, administered orally or via injection, though underlying causes must also be addressed.

The Crucial Role of Vitamin K in the Body

Vitamin K is a fat-soluble vitamin essential for a number of critical bodily functions, most notably the regulation of blood coagulation. It acts as a vital co-factor for an enzyme that activates several key clotting proteins in the liver, including factors II (prothrombin), VII, IX, and X. Without sufficient vitamin K, these clotting factors remain in an inactive state, preventing blood from clotting effectively. Beyond its famous role in blood clotting, vitamin K is also important for bone health, contributing to the synthesis of proteins like osteocalcin, which helps bind calcium to the bone matrix.

Deficiency Disease: Vitamin K Deficiency Bleeding (VKDB)

The most significant deficiency disease caused due to lack of vitamin K is a bleeding disorder known as Vitamin K Deficiency Bleeding (VKDB). This condition is particularly prevalent and dangerous in newborns, who are born with low vitamin K stores and have sterile guts, meaning they lack the bacteria that produce vitamin K. VKDB can manifest in three different forms, depending on when it occurs:

Early-onset VKDB: This happens within the first 24 hours of life and is often associated with the mother taking certain medications during pregnancy.
Classic VKDB: Occurs between days 2 and 7 after birth and is due to the low vitamin K reserves that newborns have at birth.
Late-onset VKDB: Typically emerges between 2 and 12 weeks of age and is most common in exclusively breastfed infants who did not receive a prophylactic vitamin K shot at birth.

Symptoms of Vitamin K Deficiency

While severe bleeding, especially intracranial hemorrhage in infants, is the most life-threatening complication, vitamin K deficiency can present with a range of other symptoms.

Easy bruising or excessive bleeding: This is a hallmark sign, often seen as unusual bruises, nosebleeds, or prolonged bleeding from minor cuts.
Gastrointestinal bleeding: Symptoms can include black, tarry stools, or blood in the vomit, which indicates bleeding in the GI tract.
Blood in urine: The presence of blood in the urine, or hematuria, is another potential indicator.
Bone health issues: In the long term, insufficient vitamin K can impair bone mineralization, potentially leading to weakened bones, osteopenia, or osteoporosis.

Risk Factors for Vitamin K Deficiency

While dietary deficiency is rare in healthy adults due to the wide availability of vitamin K in food and production by gut bacteria, certain factors increase the risk.

Newborns: As previously mentioned, newborns are at high risk, which is why prophylactic vitamin K injections are standard practice.
Malabsorption disorders: Conditions like celiac disease, cystic fibrosis, or Crohn's disease can prevent the body from properly absorbing fat-soluble vitamins, including vitamin K.
Liver disease: Since the liver produces the clotting factors that depend on vitamin K, liver disorders can impair their synthesis and lead to deficiency.
Antibiotics: Long-term use of broad-spectrum antibiotics can kill the beneficial gut bacteria that produce vitamin K.
Blood thinners: Anticoagulant medications like warfarin are designed to counteract vitamin K's clotting effects and require careful monitoring of vitamin K intake.

Diagnosis and Treatment

Diagnosis typically involves a blood test to measure clotting times, such as the prothrombin time (PT) and International Normalized Ratio (INR), which will be prolonged in a deficiency. The most direct treatment is administering vitamin K, often as a supplement called phytonadione. For newborns, this is given as a single intramuscular injection shortly after birth. In adults, treatment methods and dosages vary depending on the severity and underlying cause.


Feature	Vitamin K Deficiency in Newborns (VKDB)	Vitamin K Deficiency in Adults
Primary Cause	Poor placental transfer, low breast milk content, and sterile gut bacteria.	Malabsorption issues, medication (e.g., warfarin, antibiotics), and liver disease.
Onset	Occurs within the first few weeks or months of life (early, classic, or late).	Gradual, often linked to an underlying condition or medication use.
Severe Bleeding Risk	High risk of life-threatening internal bleeding, especially in the brain.	Less common, but still a risk, especially with liver disease or overdose of anticoagulants.
Common Symptoms	Bruising on the head, bleeding from the nose, umbilical cord, or circumcision site, seizures, and pale gums.	Easy bruising, mucosal bleeding (gums, nose), heavy menstrual bleeding, and gastrointestinal hemorrhage.
Preventive Measure	Prophylactic vitamin K injection at birth.	Maintaining a balanced diet and managing underlying health conditions.
Typical Treatment	Vitamin K supplementation, sometimes with fresh frozen plasma for severe cases.	Oral or injected vitamin K, with dietary adjustments as needed.

Conclusion

The deficiency disease caused due to lack of vitamin K is primarily characterized by impaired blood clotting, with the most critical form being Vitamin K Deficiency Bleeding (VKDB) in infants. While relatively uncommon in healthy adults, it poses a significant threat to newborns and those with malabsorption disorders or liver disease. The prevention of VKDB in infants through a routine vitamin K injection at birth is a straightforward and highly effective public health measure. In adults, managing underlying conditions and dietary intake is key to prevention and treatment. If you experience symptoms like easy bruising or excessive bleeding, it is important to consult a healthcare professional for a proper diagnosis and treatment plan.

Frequently Asked Questions

The primary deficiency disease caused by a lack of vitamin K is a bleeding disorder known as Vitamin K Deficiency Bleeding (VKDB), also historically called hemorrhagic disease of the newborn.

Newborns are at higher risk because they are born with low vitamin K stores, have sterile intestines lacking the bacteria that produce vitamin K, and breast milk contains low levels of the vitamin.

Common symptoms include easy bruising, excessive bleeding from wounds, nosebleeds, blood in the urine or stool, and in severe cases, dangerous internal hemorrhaging.

Yes, while rare in healthy adults, it can affect individuals with malabsorption disorders (like celiac disease), liver disease, or those on certain medications that interfere with vitamin K metabolism.

A doctor can diagnose a deficiency by assessing symptoms and using a blood test called a prothrombin time (PT) test, which measures how long it takes for blood to clot.

Treatment involves administering vitamin K, often through oral supplements or injections, particularly in severe cases or for newborns who require a prophylactic shot at birth.

Yes, beyond blood clotting, vitamin K is also essential for bone health, as it helps regulate calcium and supports the synthesis of important bone proteins.