Vitamin K

Vitamin K is a nutrient that the body needs in small amounts to function and stay healthy. Vitamin K helps to form blood clots (a mass that forms when blood platelets, proteins, and cells stick together) and maintain strong bones. It is fat-soluble (can dissolve in fats and oils) and is found in green leafy vegetables, broccoli, liver, and vegetable oils. Vitamin K is also made by bacteria that live in the large intestine. Not enough vitamin K can lead to bleeding and bruising. It is a type of phylloquinone.

What is Vitamin K?

Vitamin K is a group of fat-soluble vitamins required for the synthesis of proteins needed for blood coagulation and for calcium binding in bones and other tissues.

Vitamin K Physiology

Vitamin K Deficiency

Chemical Structure of Vitamin K

Vitamin K Biochemistry

Vitamin K2: Physiological Importance and Increasing Your Intake

Newborn Vitamin K Injections

Vitamin K Uses

Sources of Vitamin K

Latest Vitamin K News and Research

Eating more leafy vegetables may reduce atherosclerotic vascular disease risk

A cup and a half of leafy green vegetables could go a long way to addressing atherosclerotic vascular diseases (ASVD's), new research from Edith Cowan University (ECU), the University of Western Australia and the Danish Cancer Institute has found.

26 Jun 2025

Berries pack more fiber and antioxidants than America’s most-eaten fruits

Replacing one daily serving of commonly eaten fruits like apples or bananas with berries significantly boosts nutrient density in USDA dietary patterns. The modeling analysis showed notable gains in anthocyanins, fiber, and vitamins, with only modest cost increases.

16 Jun 2025

New and updated clinical practice guidelines released for treatment of pediatric venous thromboembolism

The American Society of Hematology (ASH) and the International Society on Thrombosis and Haemostasis (ISTH) released new and updated clinical practice guidelines for the treatment of pediatric venous thromboembolism (VTE).

27 May 2025

Long-term study confirms safety and effectiveness of rivaroxaban for children

Venous thromboembolism (VTE) is a life-threatening complication in children with serious underlying conditions such as heart defects or cancer.

23 May 2025

Low vitamin K intake may adversely affect cognition as people get older

As scientists seek to unravel the intricate potential connections between nutrition and the aging brain, a new study from researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University is shedding light on how insufficient consumption of vitamin K may adversely affect cognition as people get older.

11 Apr 2025

Study shows how autism-linked picky eating causes serious vitamin deficiencies

Children with autism spectrum disorder (ASD) face a high risk of multiple micronutrient deficiencies, especially vitamins A, D, B12, and calcium, due to extreme food selectivity. These deficiencies can lead to severe health issues like rickets, vision loss, and immune dysfunction, even in children with normal body weight.

13 Mar 2025

Study reveals abelacimab’s potential to improve anticoagulation safety for AFib patients

Abelacimab, a factor XI inhibitor, demonstrated a 62–69% reduction in major bleeding compared to rivaroxaban in atrial fibrillation patients at moderate-to-high stroke risk, with comparable safety and efficacy. While ischemic stroke rates were slightly higher, they were not statistically significant, warranting further phase 3 trials for confirmation.

23 Jan 2025

Edoxaban proves effective in preventing blood clots, stroke after heart valve surgery

Edoxaban, an oral anticoagulant, was equally or more effective than warfarin in reducing the risk of stroke and blood clots for patients after heart valve replacement surgery, according to preliminary late-breaking science presented today at the American Heart Association's Scientific Sessions 2024.

18 Nov 2024

NSAIDs raise bleeding risk in patients taking blood thinners

People who take an anticoagulant medicine double their risk of an internal bleed if they take a type of painkiller called a non-steroidal anti-inflammatory drug (NSAID) such as ibuprofen, diclofenac or naproxen, according to research published in the European Heart Journal [1] today (Monday).

18 Nov 2024

Vitamin K2 reduces the frequency, intensity, and duration of nighttime leg cramps

A study reveals vitamin K2 significantly lowers the frequency and intensity of nocturnal leg cramps in individuals over 65, enhancing symptom management.

30 Oct 2024

Evaluating the effectiveness of GAAD for early detection of hepatocellular carcinoma

Early detection of hepatocellular carcinoma (HCC) is crucial for improving survival in patients with chronic hepatitis.

25 Oct 2024

New pro-oxidant supplement shows promise in slowing prostate cancer progression

Prostate cancer is a quiet killer. In most men, it's treatable. However, in some cases, it resists all known therapies and turns extremely deadly.

24 Oct 2024

New study reveals declining nutrient intake among U.S. women of reproductive age

Researchers compare trends in nutrient consumption from dietary sources and supplements in pregnant and non-pregnant women in the United States.

14 Oct 2024

How plant-based, Mediterranean, and Western diets affect gut microbiota and disease

Researchers examine how different dietary components affect the gut microbiome and development of non-communicable diseases.

20 Sep 2024

Daily prunes may help reduce bone loss in young women using oral contraceptives

A newly published study among 18- to 25-year-old women shows that eating about a serving of prunes daily for a year may be a safe and inexpensive solution to reduce the risk of bone loss associated with oral contraception use.

16 Sep 2024

Cruciferous vegetables like broccoli reduce blood pressure compared to root and squash vegetables

Daily intake of cruciferous vegetables significantly lowers blood pressure in mildly hypertensive adults, highlighting their role in cardiovascular health.

10 Sep 2024

Cruciferous vegetables proven to lower blood pressure more than root vegetables

Cruciferous vegetables, including broccoli, cabbage, kale, and cauliflower have been found to lower blood pressure, in comparison to root and squash vegetables, in middle-aged and older Australian adults with elevated blood pressure.

6 Sep 2024

OCEANIC-AF trial reveals inferiority of asundexian to apixaban for stroke prevention

Asundexian 50 mg daily was inferior to apixaban for stroke and systemic embolism prevention in high-risk patients with atrial fibrillation (AF), according to late-breaking research presented in a Hot Line session today at ESC Congress 2024.

1 Sep 2024

TAVI patients show no benefit from continuing oral anticoagulants

There was no apparent benefit to continuing oral anticoagulants compared with interruption in patients undergoing transcatheter aortic valve implantation (TAVI), according to late-breaking research presented in a Hot Line session today at ESC Congress 2024.

1 Sep 2024