The Dangers of Hemorrhage: What is the Main Deficiency Disease of Vitamin K?

October 19, 2025 •

3 min read

According to the Centers for Disease Control and Prevention (CDC), the routine administration of a vitamin K shot to newborns has virtually eliminated the most serious manifestation of a deficiency. This highlights the critical importance of understanding what is the main deficiency disease of vitamin K, particularly in vulnerable populations.

Quick Summary

The main deficiency disease of vitamin K is hemorrhagic disease, or uncontrolled bleeding, known as Vitamin K Deficiency Bleeding (VKDB) in newborns. This occurs due to inadequate vitamin K levels needed to produce essential blood clotting proteins. While rare in healthy adults, it is a significant risk for infants and individuals with fat malabsorption conditions.

Key Points

Hemorrhagic Disease: The main deficiency disease of vitamin K is hemorrhagic disease, or uncontrolled bleeding, known as VKDB in newborns.
Newborn Risk: Infants are at high risk for VKDB due to low vitamin K levels at birth, which is why a prophylactic shot is standard practice.
Adult Deficiencies are Rare: Vitamin K deficiency is uncommon in healthy adults, primarily affecting those with fat malabsorption issues, liver disease, or on specific medications like warfarin.
Primary Symptom: The most common and direct symptom of vitamin K deficiency in both adults and infants is excessive bleeding and easy bruising.
Dietary Sources: Excellent dietary sources of vitamin K include green leafy vegetables, fermented foods like natto, eggs, and certain vegetable oils.
Diagnosis and Treatment: Diagnosis is typically done with a blood test (PT test) that measures clotting time, and treatment involves vitamin K supplements.

Understanding the 'Clotting Vitamin'

Vitamin K is a fat-soluble vitamin crucial for producing clotting factors required for blood coagulation. A lack of sufficient vitamin K impairs the blood's ability to clot, leading to the primary deficiency disease associated with this nutrient. Vitamin K exists as K1 (phylloquinone) in plants like leafy greens and K2 (menaquinone), produced by gut bacteria and found in fermented and animal products.

Vitamin K Deficiency Bleeding (VKDB): The Primary Disease

The main deficiency disease of vitamin K in newborns is Vitamin K Deficiency Bleeding (VKDB), a potentially fatal condition characterized by uncontrolled bleeding due to inadequate clotting factors. Infants are especially vulnerable because they receive limited vitamin K from the placenta, are born with sterile guts lacking K2-producing bacteria, and breast milk contains low levels of the vitamin. A routine vitamin K injection given to newborns shortly after birth effectively prevents VKDB.

VKDB is categorized into three types based on the onset of bleeding:

Early VKDB: Occurs within 24 hours of birth, often associated with maternal medication use.
Classic VKDB: Occurs between 2-7 days after birth, commonly seen as bleeding from the umbilical cord or circumcision.
Late VKDB: Develops between two weeks and six months of age, posing a higher risk for breastfed infants or those with malabsorption issues. This type can cause dangerous intracranial hemorrhage.

Deficiency in Adults: Causes and Symptoms

While VKDB is primarily an issue for infants, adults can also experience vitamin K deficiency, leading to excessive bleeding. This is uncommon in healthy adults due to sufficient dietary intake and K2 production by gut bacteria. However, certain medical conditions or medications can cause deficiency.

Potential causes in adults include:

Malabsorption disorders affecting fat absorption.
Liver disease, which impacts clotting factor synthesis.
Medications like warfarin or long-term antibiotics.
Severe malnutrition or alcoholism.

Symptoms in adults may include:

Easy bruising and bleeding.
Nosebleeds and bleeding gums.
Excessive bleeding from minor injuries.
Heavy menstrual bleeding.
Blood in urine or stool.

Diagnosis and Treatment

Diagnosing vitamin K deficiency often involves a physical exam and a prothrombin time (PT) blood test, which measures how quickly blood clots. An elevated PT suggests a potential deficiency. Treatment varies by severity and cause, ranging from dietary adjustments or oral supplements in adults to injectable vitamin K for severe cases or malabsorption. Active VKDB in infants is treated with vitamin K and sometimes fresh frozen plasma.

Food Sources of Vitamin K

Preventing deficiency in adults primarily involves a diet rich in vitamin K. K1 is abundant in vegetables, while K2 is found in fermented foods and animal products.

Excellent sources of Vitamin K1:

Leafy greens (kale, spinach, collards)
Broccoli and Brussels sprouts
Cabbage and lettuce
Asparagus

Sources of Vitamin K2:

Natto (fermented soybeans)
Hard cheeses and other dairy
Egg yolks
Animal liver and other meats

Comparison of Vitamin K1 and Vitamin K2


Feature	Vitamin K1 (Phylloquinone)	Vitamin K2 (Menaquinone)
Primary Source	Green leafy vegetables, vegetable oils	Fermented foods, animal products, gut bacteria
Absorption Rate	Absorbed less efficiently than K2	Absorbed more readily, especially MK-7
Storage Location	Liver, heart, pancreas	Brain, kidneys, other tissues
Primary Function	Blood clotting (coagulation)	Bone health, cardiovascular health, various cellular processes
Role in Deficiency	The primary form in a dietary deficiency leading to clotting issues	A deficiency may impact bone mineralization and arterial calcification

Conclusion

Severe vitamin K deficiency, particularly the hemorrhagic disease it causes (VKDB), is uncommon in healthy adults but poses a serious risk to newborns. The standard practice of administering a vitamin K injection to newborns is vital for preventing this potentially fatal condition. Adults can prevent deficiency through a balanced diet rich in vitamin K, especially those with conditions affecting absorption or those taking interfering medications. Anyone experiencing abnormal bleeding should consult a healthcare provider, as it is a key symptom of this deficiency.

Disclaimer: The information provided in this article is for informational purposes only and does not constitute medical advice. Consult a healthcare professional for diagnosis and treatment.

Frequently Asked Questions

The main role of vitamin K is to assist in the production of proteins necessary for blood clotting, or coagulation, which prevents excessive bleeding.

Symptoms in adults can include easy bruising, nosebleeds, bleeding gums, heavy menstrual bleeding, and blood in the urine or stool.

Newborns are at risk because they have limited vitamin K reserves at birth, their gut lacks the bacteria to produce it, and breast milk contains low levels.

The most effective method of preventing VKDB is the routine administration of a single vitamin K shot to newborns shortly after birth.

Conditions that impair fat absorption, such as celiac disease, cystic fibrosis, and inflammatory bowel disease, increase the risk, as do liver diseases and chronic alcoholism.

Treatment involves vitamin K supplements, which can be taken orally or, in more severe cases, administered via injection.

Yes, medications that interfere with vitamin K metabolism, such as the blood thinner warfarin and certain long-term antibiotics, can lead to a deficiency.

Excellent food sources include green leafy vegetables like kale and spinach, fermented foods such as natto, and certain vegetable oils.