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Supplementing vitamin D3 and K2 comes with all the benefits of vitamin D and vitamin K, but also some unique health benefits that are only unlocked when these two vitamins are used together.
New research is revealing this game-changing pair of vitamins and their effect on our hearts, our bones, and our blood sugar.
In this day and age, it’s important to invest in your health using the most up-to-date science. That’s where vitamins D3 and K2 enter the scene.
Vitamin D3 Benefits
Vitamin D is sometimes called the “sunshine vitamin” since people naturally get it from sunlight (UVB rays). Though vitamin D2 is the vitamin you get from sunshine, most scientific studies are conducted using vitamin D3, as that’s what you can absorb best from dietary supplements.
But how does Vitamin D3 differ from its counterparts?
Vitamin D1 is actually not a single compound, but a mixture of compounds, mistakenly identified as one vitamin. The term vitamin D1 is no longer used.
Vitamin D2, however, is a true form of vitamin D. Found in plants, vitamin D2 is cheaper to mass-produce. You’ll find vitamin D2 in a lot of vitamin D-fortified foods.
But vitamin D3 is actually a more effective compound than D2. Maybe that’s why most vitamin D supplements are specifically D3 supplements.
Also known as cholecalciferol, vitamin D3 is a fat-soluble vitamin naturally produced in your body. Perhaps that’s why dietary vitamin D3 is better at raising your vitamin D status. Vitamin D3 is essential to your body’s calcium absorption.
Found in animal products, vitamin D3 is known to have these benefits:
- Supports strong bones
- Promotes a healthy immune system
- Prevents gastrointestinal disease
- Improves cardiovascular health
- Boosts brain health
- Improves mood
- May prevent cancer
How much vitamin D3 do you need? The Vitamin D Council recommends 5000 IU of vitamin D3 daily, which comes to about 120 micrograms (mcg).
Vitamin K2 Benefits
Vitamin K2 (specifically menaquinone-7, a form of K2) is actually produced in small amounts by bacteria in your gut. You also find K2 in animal products like fatty fish and grass-fed beef, or in fermented foods like natto.
Both forms of vitamin K are vital to your body’s blood clotting process — though K2 may be better at it. Vitamin K2 is an important nutrient apart from K1, as it also helps your body use calcium more efficiently, which impacts the health of bones and teeth.
Vitamin K2 also lowers calcium levels in your soft tissues, making for healthy blood vessels and kidneys.
So what is vitamin K1? Well, vitamin K1 can be found in common places spinach, kale, and other leafy greens. Also known as phylloquinone, up to 90% of our dietary vitamin K intake is vitamin K1 — even though K1 is poorly absorbed into our system.
Vitamin K2 is a fat-soluble vitamin that comes with its own health benefits:
- Heart health
- Healthy bones
- Strong teeth
- Cognitive function
- Neonatal health
The Food and Drug Administration recommends a daily intake of between 75 and 120 micrograms (mcg) vitamin K. This number is for healthy adults. Here is a list of good vitamin K2 foods.
How Vitamin D3 and K2 Work Together
Separately, Vitamin D3 and K2 both promote a healthy lifestyle. Together, they could be even stronger.
New research into vitamin D3 and K2 has given way to new multivitamin dietary supplements that could unlock unique health benefits to fight aging from the inside out.
1. Bone Health
Half of adults over 50 years of age have low bone mass. Bone health is a real concern as we get older. Fortunately, the pairing of vitamin D3 and K2 seems to improve bone health across the board.
A groundbreaking 2017 review compiled over 80 studies that show vitamin D3 and K2 together might be greater than the sum of their parts, when it comes to bone health.
This is likely because vitamin D gets the calcium into the blood, then vitamin K tells the calcium where it is most needed.
Animal models reveal vitamin K can effectively prevent osteoporosis, but only when paired with vitamin D.
Taking vitamin D3 and K2 together actually promotes new bone growth. In 2019, researchers observed that vitamin D3 and K2 worked in tandem to form new osteoblasts, the cells that secrete osteocalcin, which is a biomarker for new bone growth.
2. Cardiovascular Health
One in four deaths in the United States is due to heart disease. Lucky for us, it seems vitamin D3 and K2 work together to improve our cardiovascular health.
Vitamin D makes sure you have the right amount of calcium in your blood vessels. Too much vitamin D (or not enough vitamin K) means your blood calcium levels will rise.
Elevated blood calcium levels can mess with your heart:
- Fainting or fatigue
- Heart palpitations
- Irregular heartbeat
- High blood pressure
- Heart attack or stroke
However, proper blood levels of vitamin K balance out the high vitamin D levels. Vitamin K2 tells all that calcium intake where it needs to go, and your blood calcium levels are normalized.
These vitamins also work in unison to reduce inflammation. Inflammation can lead to not only osteoporosis, but also cardiovascular diseases. Reducing inflammation is beneficial to immune function and heart health.
Vitamin D3 and K2 work together in a unique way to soften your arteries and prevent cardiovascular disease.
3. Fights Diabetes
One in eleven Americans struggles with diabetes. But there are some new ways of alleviating the effects of diabetes.
Taking vitamin D3 and K2 together reduces insulin resistance.
Insulin is a hormone that plays a role in blood sugar and the storage of fat — but we’re only concerned with its effect on blood sugar today.
Insulin tells your body’s cells to take sugar (glucose) from your blood and use it for energy. However, people with type 2 diabetes have developed insulin resistance.
What is insulin resistance? This is when your body does not respond to insulin telling your body to use sugar as energy. This insulin resistance can be alleviated by — you guessed it — vitamin D3 and K2.
If diabetes goes untreated, it can lead to:
- Kidney disease
- Cardiovascular system problems
- Issues with circulatory system
- Nerve damage
Supplementing vitamin D3 and K2 is one way of improving your quality of life. But be sure to consult your doctor about what needs to be done to keep diabetes at bay.
4. Avoiding a Deficiency
An obvious benefit to supplementing vitamins K2 and D3 is to avoid a deficiency in either.
Two in five Americans don’t get enough vitamin D in their diets. Your kidneys should take vitamin D and turn it into calcitriol — its more bioactive form. In rare cases, your kidneys don’t carry out this process effectively, which also leads to low vitamin D levels.
Since vitamin D is essential to the absorption of calcium, a deficiency can lead to bone loss, osteoporosis, bone fractures, and muscle weakness. Low vitamin D levels have been linked with heart disease.
In children, a vitamin D deficiency can cause rickets.
Vitamin K1 deficiency is rare in adults, but it does occur in almost half of newborns.
If you have a vitamin K deficiency, you can expect to see these kinds of symptoms:
- Easily bruised
- Bleeding that doesn’t stop
- Blood clots under your nails
- Red or black stool
The presence of matrix Gla protein is one way to test if you have a vitamin K deficiency. Matrix Gla protein is associated with cardiovascular disease, as well as low vitamin K levels.
Interestingly, it seems that a vitamin K2 deficiency is incredibly common but doesn’t cause short-term effects like a K1 deficiency. Instead, this deficiency plays out in chronic diseases and symptoms.
A 2007 study confirms that, in fact, the majority of people are deficient in vitamin K2. There are many reasons for this, but one obvious one might be the way grass-fed animals produce this vitamin.
All mammals (except for humans) have a necessary enzyme for efficiently converting K1 to K2 in the gut. K1, as discussed earlier, is found in greens — anything that uses chlorophyll for energy.
Since humans don’t possess this enzyme and our gut only converts a little bit of vitamin K1, we have to get the majority of K2 via our diet. However, grain-fed animals don’t offer proteins high in vitamin K2, since they aren’t eating K1-rich foods.
Put simply: to get enough vitamin K2, you must eat grass-fed proteins or dairy products, or natto. Natto is much more difficult to find in the US than grass-fed protein or dairy, but it’s what’s used for most K2 supplements (plus, it’s a plant food and appropriate on a vegan diet).
Side Effects of Vitamin D3 and K2
High doses of vitamin D, without vitamin K to temper it, can cause high calcium levels (called hypercalcemia) in your blood. This leads to blood vessel calcification, which can lead to heart disease or stroke.
These are the most common symptoms of hypercalcemia:
- Poor appetite
- Nausea, abdominal pain
- Constipation, diarrhea
- Kidney stones
Too much vitamin K may be harmful if you’re receiving dialysis due to kidney disease. Also, very high vitamin D levels have led to kidney failure.
Vitamin D toxicity can also lead to bone loss since vitamin D takes calcium from your bones and sends it into your bloodstream. Too much vitamin D equals too much calcium taken from your bones.
Always consult your health care provider before starting a new multivitamin or calcium supplement plan.
- New research reveals that vitamins D3 and K2 are stronger together than they are alone.
- Vitamin D increases blood calcium levels. Vitamin K, especially K2, helps grow proteins that tell that calcium intake where it most needed.
- Recommended daily intake is:
- 5000 IU vitamin D3
- 75 to 120 micrograms (mcg) vitamin K2
- Vitamin D3 and K2 work in tandem to benefit your:
- Blood vessels
- There may be some side effects. If you have too much vitamin D in your blood, it can lead to digestive problems, kidney problems, or even kidney stones. But vitamin K lowers blood calcium levels.