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Much has been written about vitamin D in recent years. As reported cases of vitamin D deficiency have been increasing in incidence, public awareness on just how crucial vitamin D is for overall health has been growing too.

Vitamin D is best known for its essential role in supporting healthy bones, and we now know that it's involved in many other aspects of your health too.  Identification of the vitamin D receptor (VDR) in nearly all tissue types throughout the body tells us that vitamin D has diverse and widespread effects on most aspects of health. Vitamin D is believed to play a crucial role in disease prevention and the maintenance of optimal health. Vitamin D is vital for immune health too. Several large-scale meta-analyses have now demonstrated an association between low vitamin D levels and increased (all-cause) mortality rates. In simple terms, this means that optimal vitamin D levels have been found to be associated with a longer lifespan.1-8

Vitamin D - The 'sunshine' vitamin!

Unlike other essential nutrients, our primary source of vitamin D isn’t food, it’s sunshine! Our skin is able to make vitamin D when it comes into contact with the sun’s rays. With a distinct lack of sunshine however, especially in the colder months, supplementation is generally accepted to be the most effective way to increase levels of vitamin D in the UK.

In fact, Public Health England has responded to growing concerns around low vitamin D levels and the impact this may have on immune health by recommending that everyone should consider supplementing their diet with daily vitamin D all year round, not just in the Autumn and Winter months.

However, as with most aspects of health, the story isn’t quite as simple as that. If you choose to supplement with vitamin D, you also need to consume in your food, or take in supplement form, vitamin K2.

Here's 3 good reasons why:

1. Vitamin D3 & K2 work in partnership to support healthy bones

Vitamin K2 works together with Vitamin D3 to support healthy bones.  In simple terms, vitamin K2 helps to make sure that calcium is deposited where it needs to be in the bones and not elsewhere such as the arteries.

Numerous studies have shown that low vitamin K causes reductions in bone mineral density (BMD) and increases fracture risk.  Vitamin K2 supplementation has been shown to promote bone formation and lessen fracture risk.9-13

Research has found the combined use of vitamin K2 & D3 to be more effective than either nutrient alone for preventing bone loss and for improving bone mineral density.14

2. Vitamin D3 & K2 may slow arterial calcification

Vitamin D3 and vitamin K2 work together to produce and activate a substance called Matrix GLA Protein (MGP), found around the elastic fibres of your arterial lining.  MGP helps to protect against the formation of calcium crystals, which can lead to arterial calcification.  Current medical opinion suggests that supplementing with vitamin D3 & K2 together may help to slow the progression of arterial calcifcation, whereas vitamin D on its own may not.15-16

W23 HT66Professor Cees Vermeer, one of the world’s leading K2 researchers commented on this mechanism,

“The only mechanism for arteries to protect themselves from calcification is via the vitamin-K dependent protein MGP. MGP is the most powerful inhibitor of soft tissue calcification presently known, but non-supplemented healthy adults are insufficient in vitamin K to a level that 30% of their MGP is synthesized in an inactive form.”11

W23 HT66A large-scale European clinical trial following 4,807 subjects aged over 55 over a 7-10 year period found dietry intake of vitamin K2 to be protective against arterial calcification and cardiovascular death.  None of these beneficial outcomes were observed with vitamin K1 intake.17

3. Vitamin D3 & K2 and immune health

Vitamin D’s role in supporting balanced immune health is now well understood, but many people are unaware that vitamin K may have a part to play too.  In fact, reduced vitamin K status has been identified as a potentially modifiable prognostic risk factor in COVID-19. In a study published in Clinical Infectious Diseases in May 2020, researchers aimed to evaluate whether vitamin K status is reduced in patients with severe COVID-19. Included in the study were 123 patients admitted with COVID-19 and 184 controls. They found that vitamin K status was reduced in patients with COVID-19 and related to poor prognosis. Low vitamin K was also found to be associated with accelerated elastin degradation. The researchers concluded that an intervention trial is now needed to assess whether vitamin K administration improves outcomes in patients with COVID-19.

MK-7 – The most effective form of vitamin K2

There are several different forms of vitamin K2, one of which is MK-7, and this is generally accepted to be one of the most effective, since it has a much longer half life (3 days) than others. A longer half-life means it has a much better chance of building up a consistent blood level. 

Learn More
• SUPPLEMENTS:  Vitamin D3 Range
• VITAMIN D + BABIES:  How Much Vitamin D Should Babies Have?
• BENEFITS:  Vitamin D Beneficial for Eczema & Psoriasis

Complex Science – Simple Message

Whilst the science may be complex, the message is simple. If you’re thinking of supplementing with vitamin D, you also need to think about vitamin K2 too.


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