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The Ugly Truth About Vitamin D

And How Taking It The Way
Most Doctors Recommend
Could Actually Kill You...

If you’re dutifully taking your Vitamin D every day, you could be putting yourself at risk.

Hi, it’s Dr. Mark Rosenberg, and if you’re one of my many readers over the age of 50, please take a moment and read this important article.

It could save, and extend, your life.

Don’t get me wrong – Vitamin D is one of the most important supplements to take as you age.

(And if you’re not currently taking it, it’s even more important you read on. Because odds are, you’re severely deficient in this essential vitamin).

In fact, as people age, the risk for vitamin D deficiency increases. The percentage of older adults suffering from vitamin D deficiency ranges anywhere from 20% to 100% in the US. 1

Why? The major risk factors contributing to vitamin D deficiency in seniors include low nutritional intake of vitamin D... gaining weight... the outer skin unable to synthesize Vitamin D... and spending less time outdoors. 2,3

I Call It The “Sunshine Deficit”

As a result of a sunshine deficit, Vitamin D deficiency has been linked to various health problems.

These include cognitive decline... depression... osteoporosis... cardiovascular disease... hypertension... diabetes... and cancer. 4 5

Unfortunately, it gets worse...

That’s why in this article, I’m going to expose a dangerous truth about taking Vitamin D as most doctors recommend

And then I’ll share with you the one simple step... that not only protects you against dreaded Vitamin D side effects... but also multiplies the benefits FAR BEYOND anything Vitamin D on its own can provide. 6

Now let’s be clear:

It’s Critical You Add Vitamin D
To Your Daily Routine… ESPECIALLY
During These Scary Times

There are 79,854 published studies proving how important it is.

Many studies have now shown D3 can reduce the severity of colds and viruses, including coronavirus COVID-19. 7 8

How?

Researchers believe it can help prevent the overproduction of inflammatory cytokines – the destructive immune system proteins that can attack healthy tissue, including lungs, heart and brain.

For example, a recent study found that vitamin D supplementation may help improve the outcomes of patients infected with COVID-19.

The study concluded:

“The results suggest that an increase in (vitamin D3) level in the body could either improve clinical outcomes or mitigate worst (severe to critical) outcomes, while a decrease in (vitamin D3) level in the body could worsen clinical outcomes of COVID-2019 patients.”

Clearly, now more than ever, it’s time to ensure your vitamin D levels are in check.

Now, Vitamin D3 should not be considered a cure, treatment, or preventative for COVID19 or any other disease. But if you care about the health of yourself and your loved ones as much as I do, then D3 needs to be on your list.

And it’s protective benefits are only the start.

Countless studies reveal the right D3 levels support everything from an upbeat, elevated mood, to improved energy production, to deep, restful sleep. 9

What’s more, most Americans – a whopping 57.1% - are horribly deficient in this important super-vitamin. 10

And if you live somewhere that doesn’t get 365 days of sun, there’s a good chance your D3 levels are very low. 11

Vitamin D3 - The Hidden Danger

Here’s the problem:

One of Vitamin D’s primary roles is to help you process, and absorb calcium12

… calcium that should be getting to your bones, to keep them strong.

Unfortunately, D3 doesn’t control where that calcium goes.

In fact, “misdirected calcium” can create huge health problems, including calcified arteries, kidney stones… the list goes on. 13

I’ve read far too many stories about people who had heart attacks because their arteries were corroded with calcium

… people who could have been saved - IF they’d know what I’m about to share next.

(And if you’re also supplementing with calcium, then your risk is even higher.)

Most Doctors Simply Do Not Know This...

They read a study, they recommend the vitamin (if they recommend vitamins at all), and then they get on with watching the news or playing some golf.

But I’m not afraid to admit it – I may be a little “weird”.

I’m deeply fascinated with how our bodies work, so whenever I read a promising study, I’ll often spend the next week or so diving into all of the surrounding research.

I need to understand the “biochemical pathways” that this nutrient works on…

And I also need to know how it affects other processes in the body.

It was this exact process that led me to discover Vitamin D’s dangerous side effects.

But thankfully…

There’s A Simple Fix for This Vitamin D Paradox:

A certain miracle nutrient which completely neutralizes the “misdirected calcium” problem.

Not only that but it also…

  • Helps you maintain razor sharp brain function 15
  • Helps balance the inflammatory response 16
  • Protects the brain from hailstorms of “free radicals” 17
  • Helps you produce more energy 18
  • Provides natural management of aches and discomforts 19

…and amazingly, it’s something that almost no one talks about.

Miracle Nutrient Vitamin K2:
Your “Calcium Coach”

Specifically, Vitamin K2-7.

(The “7” form is very important, as you’ll see in a bit).

You can think of Vitamin K2 as the “Calcium Coach.”

Vitamin D3 helps you absorb extra calcium… and hands it off to Vitamin K2, which directs it into our bones, instead of our arteries.

So you avoid cardiovascular damage…

And you’re left with stronger, healthier, fortified bones.

In fact, a randomized clinical trial showed that Vitamin K2-7 improved bone strength, bone mass, and prevented participants from experiencing age-related bone loss. 20

But it gets even better. Because…

Vitamin K2 On Its Own Is One Of The Most Powerful
Heart-Health Supplements You Can Take!

Thorough, well-designed studies have shown major improvements in heart health from taking just small amounts of Vitamin K2 every day. 21

These are the kinds of results greedy Big Pharma would love to try to bottle and markup for 10,000%...

But you can get them all combined with this one super nutrient!

And the benefits of Vitamin K2 go far beyond heart health.

K2 can protect the very “cellular power plants” that produce cellular energy. 22

It’s Like a Heavily Armed Watch Tower
For Your Body’s Precious Energy Factories

You see, all of your body’s energy production from little cellular energy factories called “Mitochondria.”

If you’re reading this, then you’re already a Sun Coast Sciences reader…

So you know our bodies are under nonstop assault by toxins and synthetic chemicals in the air we breathe, the food we eat, and the water we drink.

What you may not know is that besides creating all sorts of inflammatory stress, these chemicals are like fuel for “free radicals”.

You can think of free radicals like angry members of a militia.

They storm around your body, and attack your cells – and your mitochondria – like an enraged mob.

That leaves you feeling unenergized, getting overweight, and sick.

Yet new research has shown Vitamin K2 to be a powerful antioxidant - especially in the brain and heart. 23

K2 is like a group of armed guards in a watch tower, protecting our mitochondria from these free radical vandals.

This protection of mitochondria is one of the many reasons Vitamin K2 is so exciting...

So You Can See Why I’m A Big Fan Of K2

There’s also the research that shows Vitamin K2 helps you maintain a healthy brain, and a balanced inflammation response...24

And this is all on top of the crucially important role Vitamin K2 plays in promoting bone and cardiovascular health.

Study after study makes one thing clear:

When you combine Vitamin D3 with K2, you are looking at a life-changing “super team” of vitamins.

Once I discovered the powerful research behind this combination... I immediately began searching for the perfect product to recommend to my patients.

To my initial shock, it didn’t exist!

I discovered - and this is extremely important - you don’t just want any-old Vitamin K2.

You see, the “off the shelf” K2 that you’ll find at places like Amazon or GNC, is actually known to researchers as the compound K2-4.

This form of low-quality K2-4 is quickly eliminated from your body… so people who take it miss out on many of the benefits K2 has to offer.

But about five days into my research, I discovered a special variant, K2-7.

And the benefits of K2-7 vs. K2-4 are astonishing.

Vitamin K2-7 reaches a much higher peak concentration… and it stays in your body for nearly 5 times as long as K2-4.

The implications of this are huge. 25

In fact, a recent study showed you’d need 1,000 times the dose of vitamin K2-4 just to get just SOME of the benefits of Vitamin K2-7: 26 27

Unfortunately, nothing I could find had combined D3 and K2 in the clinically proven ratios, at the correct doses, using the highest quality source of research backed K2-7 also known as “MenaQ”.

Because of this, I created my very own formulation...

D3Shield:
The Ultimate Pairing
Of Vitamins D3 + K2

“I sleep better at night, and
I have more energy during the day.”

-- Roberta, Verified Customer

D3 Shield is a clinical-grade, D3 + K2 supplement, in addition to other co-nutrients.

It’s made with the most effective ingredient profile in existence, to boost your mood, support healthy bones and whole body wellness.

It works, it works quickly, and it’s one of the most powerful tools you can possibly have on your side when it comes to mood improvement, heart health, and staving off age-related issues with bone densities.

The Top Reasons To Take D3 Shield
(According To The Clinical Studies)
Supports Strong, Healthy Bones

When your body doesn't have enough calcium in your blood, it sucks the calcium it needs out of your bones. And soft, spongy, frail bones are easily fractured - or worse.

But between the Vitamin D3 that gets extra calcium back into your blood... and the Vitamin K2 that gets the extra calcium in your bones... D3 Shield will have you feel like you have the strong, powerful bones of a 20 year old.

Feel free to enjoy the activities you love without fear of harming yourself, knowing your body can withstand the impact!

Gives Deep, Restorative Sleep

Research shows low levels of Vitamin D have been linked to problems with sleep, and sleep disorders.

But you can get rid of fragmented and restless sleep by boosting your vitamin D levels with D3 Shield, and finally wake up feeling rested... feeling like yourself again.

Support Your Immune System

Vitamin D is critical for a healthy, balanced immune system.

It regulates the many immune cells that work as your body's defense system, protecting you from illnesses both little, and large.

Other studies also point to Vitamin D deficiency as a potential risk factor for out of control inflammation.

So making D3 Shield a daily habit can make you feel clearer and better than you have in years.

But there’s more...

Uplifts and Boosts Your Mood

Serotonin and dopamine are our bodies natural “happy” chemicals. They help us feel pleasure, motivation, and importance.

Because Vitamin D3 helps regulate serotonin and dopamine production, it plays a big role in supporting a positive and happy mood.

Just think of how great it feels to get some sun on a comfortably warm spring day... then imagine having that upbeat outlook 365 days of the year by taking one or two easy to swallow capsules of D3 Shield… - even in the dead cold of winter.

Supports Your Heart Health

Research has found that Vitamin D3 significantly reduces stress in the vascular system... acting as a shield to block rampaging free radicals.

Vitamin D3 also may be a powerful trigger for increased Nitric Oxide, which improves blood flow.

So when you combine the powerhouse K2 and D3, you can expect clean, unimpeded, healthy blood flow… and vibrant heart health to go along with it!

Provides Natural Relief From Aches And Discomfort

Did you know your bones can actually ache when they’re weak? Especially in the lower back, pelvis, hips, legs and ribs?!

Research has shown this may be because of a deficiency in Vitamin D and Calcium.

Thankfully, with the one-two punch of Vitamin D3 and K2 inside D3 Shield... you’ll have the building blocks necessary for strong, healthy bones.

Additional studies also point to people experiencing real relief from unnatural discomfort and excessive muscle pain once they restore their Vitamin D levels.

Improves Your Body’s Ability to Produce Natural Long-Lasting Energy

Sugar. Environmental Toxins. Metals. Pesticides. All can produce free radicals, which may cause damage to your mitochondria.

The mitochondria is the “powerplant” of your cells, responsible for your energy… so the more of them that you have running at full capacity, the more energy you’ll have!

Research has shown vitamin K2 acts as a powerful antioxidant, and prevents damage to your mitochondria. Other studies show Vitamin D also plays a big supporting role in energy production in mitochondria.

The Studies Are Clear –
You Want To Be Taking D3 And K2-MK7!

There’s been an explosion of research on Vitamin D3 and K2 recently, showing the many reasons to take the 2 Super Vitamins in D3 Shield.

Here are what just a few of the studies say:

This study shows the percentage of women and men deficient in Vitamin D by age group. 28

When you add them up, you’ll see that at least 50% of people over 19 years old are Vitamin D deficient… could you be one of them?

In another study, the Vitamin D3/K2 complex administered increased the cells responsible for supporting strong, healthy bones (and they weren’t even using K2-7!).

Figure 1A shows the increase in inflammatory markers (red) associated with a vitamin D deficiency. 29 Needless to say, that’s a bad thing!

Figure B shows the percentage of cell death in sick human bladder cells. 30

The more Vitamin K2 was administered, the more sick cells died - up to 50%. That’s a powerful boost in balanced immune system function!

This graph shows Vitamin K2-7 is incredibly bioavailable.

It’s not about what you put in your body - it’s about what you can absorb and use!

In this study 31, participants took a complex which included Vitamin D3 and K2. The results were significantly increased bone density in neck, hip, and lumbar spine areas. 

The study also showed positive effects on inflammatory status and improved quality of life (especially related to sleep) for participants.

The Clinical Trials Are Clear...
D3 Shield’s Ingredients Are The Best Way To
Enjoy Healthier Bones, Deeper Sleep
And A Boosted Immune System...

As you know, Sun Coast Sciences supplements are not cheap.

That’s because there’s a tremendous amount of research that goes into them. We cut zero corners.

For example, I could have saved some money if I’d gone with a low-grade K2-4.

But if we’d done that, I simply couldn’t stand behind it.

Why D3 Shield’s Retail Price Is So High

Yes, I admittedly went overboard on this formula.

But that’s because it’s so important to take, and so important to get right.

In addition, the cost of K2-7 is comparably high. (There’s a reason why almost no one else uses it in their formulas.)

The D3 I selected isn’t cheap either.

That’s why one month’s supply of D3 Shield is $59.95.

Granted, it’s worth every penny.

This is one of the most important supplements that every person over 50 should be taking.

What’s Inside D3 Shield...

All Sun Coast Sciences formulations are personally designed by myself to ensure accurate clinical dosing, the best ingredients, with superior bioavailability.

In D3 Shield, you’ll find…

  • 5000 IU of Vitamin D3: While there’s no consensus on how much D3 you need every day, many clinical studies show the greatest benefits occur with 1000-5000 IU daily. I selected the upper boundary of this amount, to make sure you’re getting adequate D3, no matter what your lifestyle
  • Vitamin K2-MK7: There are two forms of Vitamin K2: K2-4, and K2-7.

    Many of the popular K2 supplements contain the cheaper form of K2-4. Yet it’s been shown that K2-7 can be up to 1000 times more effective than K2-4, and that it continues to work in the body for five times as long. 32

    That’s why I chose to include K2-7 in D3 Shield.
  • Calcium: As we age, our bodies need more calcium to keep our bones strong.

    So I included 210mg of easily absorbed Calcium Bicarbonate in every capsule of D3 Shield.

  • BioPerine: To ensure maximum bioavailability – how well these nutrients are absorbed by your body – I have also included BioPerine.

    This patented ingredient has been clinically proven to increase bioavailability of a range of nutrients.

Great News!
As A Sun Coast Sciences Insider
You Qualify For A Special Discount...

The $59.95 retail price is for people who go and buy D3 Shield at the store. That’s what I have to charge to cover my costs, and pay the “middleman markup.”

But your bottle of D3 Shield is available at a 33% savings – just $39.95 for a one-month supply.

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

Save 50%

And when you order 3, or 6 bottles at a time, an even deeper discount is available.

In doing this, we’re making almost nothing on this formula – but that’s ok, as long as it means getting this incredible product into the hands of our loyal customers.

My suggestion would be this... order 3 bottles to get the most bang for your buck, AND give yourself more time to feel the wonderful immunity-boosting, mood-lifting, sleep-enhancing benefits of D3 Shield.

Don’t Love It? Then Don’t Pay For It…
(“You Can’t Lose” Refund Policy)

We’re so confident D3 Shield will work for you, you have a whole year to ask for a refund!

Not 30 days. Not 60 days. A whole 365 days.

Simply call or write to us - we’ll make it easy for you, and we’ll process your refund quickly and professionally.

Because if D3 Shield doesn’t work for you, we don’t deserve your money.

How Much To Take
(And When To Take It)

D3 Shield can be taken once, or twice a day.

For maximum immune health benefits, consider taking two capsules per day.

This dosage delivers a potent 10,000 IU of Vitamin D3 – and with Vitamin K2 onboard, you’ll be protecting your arteries, your brain and your mitochondria, as well.

Since both Vitamins D3 and K2 are fat soluble, you’ll get best results if you take D3 Shield with your meals.

So make sure to include some olive oil, coconut oil, butter or ghee for maximum absorbency.

I recommend taking D3 Shield with your first one or two meals of the day.

Some customers report improvements in their health in four to six days, while for others it takes four to six weeks. It will depend on how deficient you are in Vitamins D3 and K2.

Our customers who report the best results typically take 2 capsules of D3 Shield every day.

This is why we offer a convenient Subscribe & Save Program for customers who want to make D3 Shield a daily part of their lives.

Order With Confidence
(We’ve Got Your Back)

All Sun Coast Sciences Orders Come With:

  • Low-Cost, or Free Shipping: You’ll typically pay no more than $5 for shipping, and many of our packages include free shipping. We ship USPS First Class, and packages go out every night of the week. Most customers receive their orders in four days or less.

  • A 365-Day Guarantee: If you don’t love our products, just call or write in, and we’ll be happy to refund you. We make it easy and hassle-free to get your money back

  • 3rd-Party Testing: All of our ingredients are tested for purity upon receipt. Then, after each production run, our products are inspected at a third-party lab for integrity and potency. What you see on the label is what you get.

  • No hidden health risks: I am extremely careful about ingredient selection. Whenever possible, I choose certified NON-GMO ingredients. And when our products contain allergens, we make sure it’s clearly labeled.

Get Your D3 Shield Now

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

Save 50%

For your overall health and longevity, I urge you to get started on a Vitamin D3+K2 habit…

…and if you’re serious about doing it right, then I believe that our D3 Shield formula is your very best choice.

Our shipping is fast and free, and our quality is simply unparalleled.

Get started right now, and you’ll receive your own supply in just a few short days.

To your best health,

Dr. Mark Rosenberg

 

P.S. One more thing. It may be important. 

Want to take higher doses of D3?

There’s major benefits but also risks in doing that with D3 alone.

However, when you also supplement with K2, specifically K2-7, you’re safe to take up to 10,000 IU of D3 a day!

(and maybe even more – but please check with your doctor first)

This means you experience:

  • A Powerful Immune System

  • Strong, Supportive Bones

  • Healthy, Natural Energy

  • An Upbeat Mood

So go ahead and order your bottle of D3 Shield with K2 right now.

Frequently Asked Questions
With Dr. Mark Rosenberg

Question: “How is D3 Shield different from other Vitamin D supplements?”

Although Vitamin D3 is a proven supernutrient that positively affects almost all parts of the body…

Brain 33, heart 34, bones 35, muscles 36, joints 37 - you name it, vitamin D3 can help…

What most people don’t know is that Vitamin D3 supplementation can be deadly without Vitamin K2.

Among its many benefits, Vitamin D3 helps you absorb more calcium.

But unless that calcium is directed into your bones, it can build up as arterial deposits. Imagine a dam made of calcium building up, blocking your blood flow - not good!

Thankfully, one of Vitamin K2’s functions is to make sure all that extra calcium gets to our bones. It’s why I’ve nicknamed it “The Calcium Coach” of the body.

That’s why I’ve included the superior form of K2-7 in this special formula, and that’s why D3 Shield is simply the best you can get.

Choose Your D3 Shield Package Now

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

Save 50%

Question: What Else Is K2 Good For?

Research has proven that Vitamin K2 helps with:

  • Improving natural energy production
  • Vibrant cardiovascular health and function
  • A strong, balanced immune response
  • Healthy, non-erratic, stable blood sugar levels 38

The studies are endless, and keep getting better.

A recent trial I read showed that Vitamin K2 can improve cardiac output, equivalent to changes seen only after 6-9 months of endurance exercise… 39

It’s truly a “miracle Vitamin,” and I believe that every American should be taking it daily.

Get Your D3 Shield Now

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

Save 50%

Question: “How does the Sun Coast Sciences guarantee work?”

It’s simple: if you don’t like it, you don’t have to pay for it!

And you have the rest of your life to decide.

Just call or email us, and tell us that you’re not happy with it. We won’t be offended. In fact, we’ll be happy to give you your money back, and we’ll do it cheerfully.

Get Your D3 Shield Now

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

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Question: “Are there any side-effects?”

Every single ingredient in D3 Shield has been subject to numerous clinical trials, and has proven to be safe and effective.

Vitamin K2 in particular is safe to take with blood thinning medication. The formula is non-addictive, and non-habit-forming.

Just take one or two pills every day.

Remember, the K2-7 in D3 Shield is proven to be 1000% more effective than the weaker K2-4 form of Vitamin K2…

So the amount of K2-MK7 in D3 Shield not only helps to keep your arteries free of calcium deposits…

But I’ve ensured there’s enough of a dose for you to feel the sleep enhancing, mood improving, bone strengthening effects.

Choose Your D3 Shield Package Now

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

Save 50%

Question: “Are there any hidden charges or forced subscriptions?”

The answer is flat-out no. We don’t engage in unethical business practices at Sun Coast Sciences.

Every single product we release is backed by strong science, and is correctly dosed for maximum potency and effect.

I’ve put many decades of clinical and ER experience as an MD on the line. And I go one step further, making sure that these ingredients work in the real world.

So back to the billing, heck no, there are no hidden charges! And we definitely don’t force a subscription on you. Of course, you’re welcome to choose – for yourself – if you’d like to start a monthly shipment of D3 Shield.

If you do, you’ll get the highest savings possible!

Get Your D3 Shield Now

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

Save 50%

Question:  “I don’t feel comfortable ordering online, can I talk to someone?”

Of course you can!

Just call us at 1-888-281-6816. You’ll speak to one of our incredibly friendly Customer Happiness Representatives (seriously, they’re really great to talk to), and they’ll be happy to answer your questions and help you place your order.

Question: “How long will it take me to start seeing results on D3 Shield?”

I’m going to be honest here… and this might hurt sales, but I don’t care.

The effects of D3 are subtle.

It’s rare that I give it to someone, then have them come back a week later, saying “holy moly, I feel AMAZING!”

That’s because D3 + K2 works in so many ways, on so many pathways in your body, that the changes happen more slowly.

So what you’re much more likely to notice is that you’re sleeping better a month from now. You’re likely to notice an improved mood… one day you’ll be walking around feeling like you’ve been bathing in sunshine, and it’ll just kind of “hit you” that the D3 Shield is working.

When activities that used to exhaust you feel like a walk in the park…

You’ll know without a doubt that the D3 Shield formulation is working its magic.

And best of all, you’ll know that your heart, your bones and your brain are all getting the nutrients and protection they need to help you enjoy the best days that lie ahead.

Choose Your D3 Shield Package Now

6 BOTTLES

Normally: $359.70

$119.85

Save 67%

3 BOTTLES

Normally: $179.95

$74.97

Save 58%

1 BOTTLE

Normally: $59.95

$29.97

Save 50%

References:

1. Holick MF, Binkley NC, Bischoff-Ferrari HA, Gordon CM, Hanley DA, Heaney RP, et al. Evaluation, treatment, and prevention of vitamin D deficiency: an endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2011;96(7):1911–30. http://dx.doi.org/10.1210/jc.2011-0385. [PubMed]

2. Chan R, Woo J. The value of vitamin D supplementation in older people. Nutritional Therapy & Metabolism. 2011;29(1):8–21.

3. Chowdhury R, Kunutsor S, Vitezova A, Oliver-Williams C, Chowdhury S, Kiefte-de-Jong JC, et al. Vitamin D and risk of cause specific death: systematic review and meta-analysis of observational cohort and randomized intervention studies. BMJ. 2014;348:1–13. http://dx.doi.org/10.1136/bmj.g1903.

4. Holick MF. Vitamin D: a delightful solution for health. J Investig Med. 2011;59(6):872–80.

5. Hossein-nezhad A, Holick MF. Vitamin D for health: a global perspective. Mayo Clin Proc. 2013;88(7):720–55. http://dx.doi.org/10.1016/j.mayocp.2013.05.011.

6. https://www.ncbi.nlm.nih.gov/pubmed/23525894

7. Ali Daneshkhah, Vasundhara Agrawal, Adam Eshein, Hariharan Subramanian, Hemant Kumar Roy, Vadim Backman. The Possible Role of Vitamin D in Suppressing Cytokine Storm and Associated Mortality in COVID-19 Patients. medRxiv, Posted April 30, 2020

8. Petre Cristian Ilie, Simina Stefanescu, Lee Smith et al. The role of Vitamin D in the prevention of Coronavirus Disease 2019 infection and mortality, 08 April 2020, PREPRINT (Version 1) available at Research Square

9. https://www.ncbi.nlm.nih.gov/pubmed/22583560 

10. https://www.ncbi.nlm.nih.gov/pubmed/18844843 

11. https://www.ncbi.nlm.nih.gov/pubmed/18844843 

12. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3571641/#B14-nutrients-05-00111 

13. https://www.ncbi.nlm.nih.gov/pubmed/10838649

14. http://www.ncbi.nlm.nih.gov/pubmed/15557705 

15. https://www.ncbi.nlm.nih.gov/pubmed/24108469 

16. http://www.ncbi.nlm.nih.gov/pubmed/18006902 

17. https://www.ncbi.nlm.nih.gov/pubmed/24108469 

18. https://science.sciencemag.org/content/336/6086/1241 

19. https://www.ncbi.nlm.nih.gov/pubmed/20378261 

20. https://www.ncbi.nlm.nih.gov/pubmed/23525894 

21. https://www.ncbi.nlm.nih.gov/pubmed/15514282 

22. https://science.sciencemag.org/content/336/6086/1241 

23. https://www.ncbi.nlm.nih.gov/pubmed/24108469

24. https://www.ncbi.nlm.nih.gov/pubmed/24108469

25. http://menaq7.com/k-vitamins-overview/what-are-k-vitamins/ 

26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1915640/ 

27. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1915640/ 

28. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3571641/

29. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5413041/figure/pone.0175517.g001/

30. http://www.ncbi.nlm.nih.gov/pubmed/20424220

31. https://www.ncbi.nlm.nih.gov/pubmed/28646812