Whole-Body Benefits of Vitamin K

Research released in 2021 by the American Heart Association reveals that higher vitamin K intake lowered risk of atherosclerotic cardiovascular disease and hospitalizations.¹

This 2021 study published in the Journal of the American Heart Association¹ corroborates data that have accumulated since the late 1990s showing that vitamin K reduces arterial calcification.^2-6

In addition, vitamin K has also been found to:

• Strengthen bones and reduce fracture risk,
• Lower risk of developing diabetes,
• Promote brain health, and
• Reduce inflammation.

In one study, adults aged 55 and older with the highest intake of vitamin K2 had a 57% lower risk of death from coronary heart disease over 10 years—and a 26% lower risk of death from any cause.⁷

Readers of this publication began supplementing with higher-potency vitamin K in 1999.

What is Vitamin K?

Vitamin K is a fat-soluble vitamin that is required to activate many proteins in the body, known as vitamin K-dependent proteins.

There are two main types of vitamin K.

Vitamin K1 is present in green leafy vegetables.^8,9

It is best known for its ability to promote healthy blood clotting and prevent abnormal bleeding.^10,11 It works by activating vitamin K-dependent coagulation proteins.

In the U.S., the American Academy of Pediatrics recommends that all newborns receive a vitamin K1 injection shortly after birth to prevent potentially lethal vitamin K deficiency bleeding.¹²

Vitamin K2 is known as menaquinone and has several subtypes. It plays vital roles in the health of bones, the heart, the brain, the immune system, and more.¹³

Types of Vitamin K2

Vitamin K2 exists in several forms.^14,15 Among these, menaquinone-4 (MK-4) and menaquinone-7 (MK-7) have received the most attention.

MK-4 is found mainly in dairy foods like butter, milk, and cheese, and can also be formed by conversion of dietary vitamin K1 (phylloquinone).^16,17

MK-7 is primarily present in fermented foods, such as some cheeses, kefir (fermented milk), sauerkraut, and natto (fermented soy). MK-7 can also be produced by bacteria in the intestinal tract.^16,17

Building Stronger Bones

Vitamin K2 improves bone quality and strength, which may reduce the risk of fractures and hospitalizations.

It does this mainly by activating a vitamin K-dependent protein known as osteocalcin,¹³ which binds to calcium and promotes bone formation.^18,19

In 2020, Chinese researchers evaluated the effects of vitamin K2 intake on bone mass. The study showed that taking 90 mcg of vitamin K2 daily in the form of MK-7 for one year significantly reduced bone loss in postmenopausal women.²⁰

In another study, healthy Japanese women receiving 1,500 mcg per day of vitamin K2 in the form of MK-4 for four weeks had higher osteocalcin levels than those who received a placebo. The researchers concluded that MK-4 may help maintain bone health in postmenopausal women.²¹

The combined effects of vitamin D and vitamin K2 on bone health may be greater than either vitamin alone.

That’s because vitamin D is essential in the expression of vitamin K-dependent proteins such as osteocalcin, while vitamin K2 activates them. Vitamin D also increases the intestinal absorption of calcium, which is then used in bone mineralization by osteocalcin.^22,23

A clinical study of postmenopausal women confirmed that high dose MK-4 (45,000 mcg) plus vitamin D was more effective at increasing bone mineral density than either MK-4 or vitamin D on its own.²⁴

The use of both vitamins together represents a viable approach toadjunctive osteoporosis treatment.⁹

Protecting the Heart

Vitamin K2 also protects against cardiovascular disease. It activates matrix Gla protein, a vitamin K-dependent protein that helps inhibit calcium from entering soft tissues like arterial walls and forming calcified plaques.^13,25

A study focusing on vitamin K intake in 564 postmenopausal women found that higher dietary intake of vitamin K2 was associated with protection against dangerous calcification of coronary arteries.²⁶ Those with the highest intake had a 20% lower rate of calcification than those with the lowest intake.

And in a study that followed more than 4,800 adults over age 55 for up to 10 years, those with the highest intake of vitamin K2 had a 57% lower rate of death due to coronary heart disease—and a 26% lower rate of death from any cause.⁷

The synergy between vitamin K2 and vitamin D also appears to have benefits for cardiovascular health.²³

A 2015 study evaluated the effects of vitamin K2 on the progression of atherosclerosis in patients with chronic kidney disease. After approximately nine months, those who received 90 mcg of MK-7 plus 400 IU (10 mcg) of vitamin D daily had less progression of atherosclerosis than those who received only vitamin D.²⁷

Help for Diabetics

Vitamin K2 intake may be associated with lower risk of developing type II diabetes and may potentially be helpful for people living with the disease.²⁸

The vitamin’s effects on glucose homeostasis may be due in part to the activation of osteocalcin. In addition to its role in bone mineralization, osteocalcin stimulates healthy insulin and adiponectin expression.²⁹

In healthy young men, taking 30,000 mcg per day of vitamin K2 (MK-4) for four weeks increased insulin sensitivity. Researchers believe that these benefits are in part due to osteocalcin’s actions.³⁰

By improving glucose and lipid metabolism, vitamin K2 may also help reduce body weight.^13,31

Researchers gave postmenopausal women either 180 mcg per day of MK-7 or a placebo. After three years, those who took vitamin K2 and experienced increased circulating levels of activated osteocalcin also had higher levels of adiponectin and decreased abdominal fat mass.³²

In another study, researchers gave vitamin D-deficient women with the hormonal disorder polycystic ovary syndrome either a placebo or a combination of calcium (1,000 mg per day), vitamin D (400 IU per day), and vitamin K (180 mcgper day).³³

After eight weeks, the women who received the combination had higher insulin sensitivity and lower insulin resistance than those who took the placebo—in addition, the combination led to a decrease in triglycerides and VLDL cholesterol.³³

Researchers have argued that the dual intake of vitamins D and K might benefit diabetics by regulating insulin secretion from the pancreas and upregulating insulin receptor genes in the body.²³

Brain Benefits

Vitamin K2 may play a role in helping to prevent neurological diseases.¹³

MK-4 is the predominant form of vitamin K present in the brain. It appears to be involved in the production of sphingolipids, a group of complex fat molecules that are components of cell membranes and present in the central and peripheral nervous system. These molecules are central to cell growth, structure, and signaling.³⁴

Studies have found that people with Alzheimer’s or Parkinson’s disease have reduced levels of vitamin K2^35,36 and potentially harmful changes in sphingolipid metabolism.³⁴

The anti-inflammatory properties of vitamin K1 may also benefit brain health. A study published in 2020 in Nutritional Neuroscience concluded that higher dietary vitamin K1 intake among Irish adults was associated with reduced inflammation and improved cognition.³⁷

Reducing Damaging Inflammation

Vitamin K2 has been shown to beneficially modulate the immune system. It inhibits several pathways involved in inflammation and in the release of pro-inflammatory cytokines.^38,39

A clinical study of women with polycystic ovary syndrome showed that oral intake of calcium, vitamin D, and vitamin K2 (MK-7) reduced markers of oxidative stress and inflammation.⁴⁰

Summary

Vitamin K has been shown to provide whole-body health benefits.

MK-4 and MK-7, the two main forms of vitamin K2, play crucial roles in preventing bone loss, protecting the heart, and potentially reducing type II diabetic risk.

These two forms of vitamin K2 (MK-4 and MK-7) may also promote healthy brain function, reduce inflammation, and help reduce vascular calcification.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.

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