Why in news?
An article published on 18 November 2025 in Business Standard drew renewed attention to Vitamin K, highlighting its roles beyond blood clotting and warning that deficiencies may be more common than previously thought. Health experts emphasised the need to recognise early signs of deficiency and to include both plant and fermented foods in the diet.
Background
Discovered in the 1930s, Vitamin K is a fat‑soluble vitamin named after the German word Koagulation because of its role in the clotting cascade. There are two main forms: Vitamin K1 (phylloquinone) found in leafy green vegetables and K2 (menaquinones) produced by gut bacteria and present in fermented foods, egg yolk and some meats. While severe deficiency is rare in healthy adults, certain groups – newborns, people with malabsorption disorders, long‑term antibiotic users and those with chronic liver disease – are at higher risk.
Functions of Vitamin K
- Blood clotting: Vitamin K activates proteins that help blood clot after injury. A deficiency leads to prolonged bleeding, easy bruising and heavy menstrual cycles.
- Bone health: It activates osteocalcin, a protein that binds calcium in the bone matrix. Adequate Vitamin K helps direct calcium to bones and reduces its deposition in arteries.
- Vascular protection: Vitamin K activates Matrix Gla Protein (MGP), which prevents calcium buildup in blood vessels. Emerging research also suggests anti‑inflammatory and neuroprotective roles.
Who is at risk?
- Newborns: Infants are born with low Vitamin K stores, and breast milk contains little of the vitamin. Without the routine injection at birth, they risk Vitamin K Deficiency Bleeding (VKDB), which can cause life‑threatening haemorrhage.
- People with malabsorption: Conditions such as coeliac disease, inflammatory bowel disease, cystic fibrosis and chronic pancreatitis impair fat absorption, reducing Vitamin K uptake.
- Liver disease patients: The liver activates Vitamin K‑dependent clotting factors; its dysfunction lowers effective Vitamin K levels.
- Long‑term antibiotic users: Prolonged use of broad‑spectrum antibiotics reduces gut bacteria that produce Vitamin K2.
- Certain medications: Cholestyramine, orlistat, some anticonvulsants and high‑dose vitamin E supplements can interfere with Vitamin K metabolism.
Sources and maintenance
- Dietary intake: Leafy greens such as spinach, mustard, fenugreek (methi), broccoli and amaranth are rich in Vitamin K1. Fermented foods like curd, certain cheeses and natto (fermented soybeans) provide Vitamin K2. Egg yolk and organ meats contain smaller amounts.
- Gut health: A healthy gut microbiome synthesises some Vitamin K2. Eating a fibre‑rich diet and fermented foods supports beneficial bacteria.
- Supplementation: Supplements may be prescribed for people at risk, but high doses can interfere with blood thinners such as warfarin. Always consult a doctor before taking Vitamin K supplements.
Symptoms and testing
Early signs of deficiency include easy bruising, gum bleeding and prolonged bleeding from cuts. Laboratory tests like Prothrombin Time (PT) and International Normalised Ratio (INR) assess blood‑clotting function. A rapid correction of PT/INR after a Vitamin K injection often confirms deficiency.
Conclusion
Vitamin K is more than a clotting nutrient – it supports strong bones and healthy arteries. While deficiency is uncommon, awareness of risk factors and inclusion of leafy greens and fermented foods in the diet can help maintain adequate levels. Newborns should always receive the Vitamin K shot at birth to prevent VKDB.
Source: ET