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Thorne Research – 3-K Complete – Vitamins K1 and K2 for Heart and Bone Support – 60 Capsules Price: $25.00 (as of 03/24/2021 07:40 PST- Details) & FREE Shipping.

  • Helping to maintain the health and elasticity of your arteries*
  • Supporting healthy bones*
  • Balancing the effects of vitamin D*
  • Thorne products contain ingredients from the purest sources worldwide. Flavors, colors, preservatives, and sweeteners derived from natural sources. Our products never contain gluten, artificial preservatives, stearates, wheat, rye, barley, eggs, nuts.
  • Thorne’s commitment to integrity and science-backed products has helped us earn the trust of thousands of health-care professionals, U.S. National Teams, the Mayo Clinic, and families around the world.

Thorne’s 3-K Complete contains three clinically studied forms of vitamin K – vitamin K1, and two forms of vitamin K2 (MK-4 and MK-7).* It contains significantly more MK-4 than most other multiple-K products on the market while the MK-7 is MenaQ7® – used in the majority of MK-7 research.

Vitamin K is an essential fat-soluble vitamin that plays a role of great importance in heart and bone health. Vitamin K is one of the main vitamins involved in bone mineralization (bone density) and blood coagulation. Vitamin K also helps protect against breast cancer, maintain brain function, and boost metabolism.

Vitamin K is found in vegetables as well as certain types of fruit, meat, dairy and fermented foods and is even produced inside your own body by your good gut bacteria.

Vitamin K is broken down into two main types: vitamin K1 (phylloquinone) and vitamin K2 (menaquinone).

  • Vitamin K1 is the most common source and is present primarily in plant foods like leafy green vegetables such as spinach and kale.
  • Vitamin K2 is found in animal products and fermented foods such as meat, dairy, and natto. Vitamin K, as mentioned before, is also produced by the beneficial bacteria in your gut microbiome.


What Are the Benefits of Vitamin K?

Vitamin K is a vitamin that supports the normal and healthy ability of the blood to clot as well as strong bones and healthy arteries.* Vitamin K works together with vitamin D in the body, much like magnesium pairs up with calcium. The result is that vitamin K and magnesium can both help keep calcium in the bones and out of the blood vessels and other soft tissues.*

The body’s process known as carboxylation, which is the activation of important proteins, appears to be at the center of most of vitamin K’s therapeutic benefits. When vitamin K is present as a co-factor, the proteins activated in this vitamin K-dependent carboxylation process include multiple blood-clotting proteins (prothrombin and others), bone mineralization proteins (osteocalcin and calbindin), and the vascular calcification inhibitor protein (matrix Gla-protein).*

3-K Complete offers support for bone, cardiovascular, and metabolic health. It also offers nutritional support for oncology patients.*

Vitamin K Helps Fight Cancer

The Department of Medicine, Division of General Internal Medicine at the University of Toronto, conducted a study in which 440 postmenopausal women with weakened bones were supplemented with vitamin K1 for two years. Results showed that taking vitamin K1 was associated with a 75 percent reduction in cancer incidence.

The American Journal of Clinical Nutrition published another study that involved 24,340 participants showed that a higher intake of vitamin K2 was associated with a reduced risk of cancer.

Vitamin K Helps Build Strong Bones

In the journal PLoS Medicine, the University of Toronto published a study that showed that supplementing with vitamin K1 cut the risk of fractures in half.

Another study out of the Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University in Boston demonstrated that a low intake of vitamin K foods was associated with low bone mineral density in women.

Vitamin K Helps with Healthy Blood Clotting

It is well-known that vitamin K has an important role in promoting the formation of blood clots. Blood clotting is an important biological process that prevents excess bleeding as a result of injury. In fact, one of the first signs of a vitamin K deficiency is bleeding from the gums or nose in addition to easy bruising.

Vitamin K Promotes a Healthy Heart

In 2009, a study published in the American Journal of Clinical Nutrition that involved 388 subjects, vitamin K1 was found to slow the progression of coronary artery calcification in older adults.

Other studies have also confirmed the beneficial effects of vitamin K1 on vascular calcification, a condition that causes blood vessels to lose elasticity due to calcium deposits in the arteries. In fact, coronary calcification is believed to be a strong predictor of coronary heart disease. For this reason, increasing your consumption of vitamin K foods can help prevent its development and keep your heart healthy and strong.

Vitamin K Can Improve Insulin Sensitivity

Insulin resistance is a condition in which the effectiveness of insulin is impaired due to constant high level of insulin for long periods of time as a result of a diet high in sugars and carb. Insulin receptors on cells lose their sensitivity to insulin.

In 2008, a study published in the journal Diabetes Care showed that 36 months of supplementation helped reduce the progression of insulin resistance in older men.

Vitamin K Can Help Boost Brain Function

Vitamin K is involved in the metabolism of sphingolipids, a compound found in cell membranes in the brain that control motor and cognitive behavior. Vitamin K also has anti-inflammatory properties that help protect the brain against free radical damage. Oxidative stress can damage your cells and may even lead to the development of conditions like Alzheimer’s disease and Parkinson’s disease.


Vitamin K deficiency is very rare; however, it could happen to certain groups of people with digestive problems that may have trouble absorbing enough vitamin K. Most people in the United States get enough vitamin K from the foods they eat. Also, bacteria in the colon make some vitamin K that the body can absorb. Severe vitamin K deficiency can cause bruising and bleeding problems because the blood will take longer to clot. Vitamin K deficiency might reduce bone strength and increase the risk of getting osteoporosis because the body needs vitamin K for healthy bones.


  • ALLERGY WARNING: This product is contraindicated in an individual with a history of hypersensitivity to any of its ingredients.
  • PREGNANCY: If pregnant, consult your health professional before using this product.
  • INTERACTIONS: As Vitamin K interferes with the effect of anticoagulant drugs (like Coumadin), the concurrent use of these agents should be avoided.


  1. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc.
  2. Vitamin K supplementation in postmenopausal women with osteopenia (ECKO trial): a randomized controlled trial
  3. Dietary vitamin K intake in relation to cancer incidence and mortality: results from the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg)
  4. Vitamin K intake and bone mineral density in women and men
  5. Vitamin K supplementation and progression of coronary artery calcium in older men and women
  6. Vitamin K status and vascular calcification: evidence from observational and clinical studies
  7. Vitamin K supplementation and progression of coronary artery calcium in older men and women
  8. Effect of vitamin K supplementation on insulin resistance in older men and women
  9. Vitamin K and brain function
  10. Vitamin K Deficiency and How to Reverse Naturally

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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