D3-K2: How This Overlooked Vitamin Synergy Can Level-Up Your Health


There are few things more important than your health. But for most of us, we don’t start worrying about our health until we start feeling sick. As a functional medicine practitioner, it’s my job to help uncover the root cause of why you are feeling the way you are, in order to treat and ultimately prevent chronic illness.

Looking at your body as a well-oiled machine with different systems all working together, it makes sense that every individual needs specific amounts of certain nutrients to keep going. If you are deficient in a specific nutrient, chances are you are more likely to get sick if you are lacking that necessary fuel.

There is no greater example for this than Vitamin D and Vitamin K2 - two of the most important nutrients when it comes to every single aspect of your health. In fact, when paired together, they have the most incredible synergy that can help bring your health back to life. So, let’s take a look at exactly what makes these two nutrients superstars for your health.


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Vitamin D

Also known as the sunshine vitamin, vitamin D is synthesized by your body when your bare skin is exposed to sunlight. No other vitamin can hold a candle to vitamin D when it comes to its importance and influence on health. Since vitamin D is fat-soluble, it acts more like a hormone than a vitamin by regulating hundreds of pathways in your body. Besides your thyroid hormones, this vitamin is the only other thing every single cell of your body needs in order to function properly. 

Benefits of Vitamin D

     1. Enhances cognitive function

Low levels of vitamin D are linked (1) to poor memory and neurological conditions like Alzheimer’s and dementia. 

     2. Strengthens immunity

Vitamin D plays an essential role in how well your immune system functions with low levels linked to autoimmune conditions like IBS (2) and Multiple Sclerosis. (3) On the flip side, symptoms have been shown to improve when vitamin D deficiencies are corrected.

     3. Alleviates depression

Ever heard of the winter blues? There’s a reason your mood dips during the cold winter months. Since vitamin D is activated by sun exposure, it also acts as an antidepressant in your body. In fact, vitamin D deficiencies are correlated with a 14% increase in depression and 50% increase in suicide. (4)

How much Vitamin D do you need?

For the most part, it is impossible to get enough vitamin D from food alone, and for the majority of us, we don’t live in a sunny place that gets you outside frequently enough to make a difference in your vitamin D levels. This is why vitamin D is so important for most people to supplement with. 

In functional medicine, we aim for an optimal range of vitamin D between 60 and 80 ng/mL. Depending on where your starting levels are, you should be taking anywhere between 2,000 and 6,000 IU of vitamin D per day. Make sure to test your vitamin D levels to find out your starting point, and retest to gauge how your vitamin D level optimization is going.

How to get more vitamin D

Since vitamin D is fat-soluble, take advantage of vitamin synergy by combining your supplement with other fat-soluble vitamins, such as A and K2. This will help make it more bioavailable and balanced. It’s also a great idea to take them with fatty foods like avocado, olive oil, wild-caught fish, and coconut to increase their bioavailability.

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Vitamin K2

Vitamin K2 is one of the most common nutrient deficiencies in the Western world, due to its limited representation in our modern diets. However, it’s one of the most essential nutrients for promoting optimal overall health and preventing long-term chronic illnesses.

Benefits of Vitamin K2

     1. Lowers inflammation

Vitamin K2 is a start when it comes to supporting healthy inflammation levels. Studies have found that vitamin K2 effectively inhibited the pro-inflammatory iNOS in the spinal cord and brain immune systems in rats that were showing symptoms of multiple sclerosis. (5) 

     2. Protects against cancer

While there are several types of K2, MK-4 works to regulate gene expression in specific ways that no other form of vitamin K does and plays an exclusive role in cancer protection.

     3. Bone health

Your body’s skeletal system is constantly replacing itself. During this process the molecule osteoclacin takes calcium and delivers it to your bones. However, osteoclacin is only activated by vitamin K2, making it an essential part of healthy bone structure as we age.

     4. Prevents heart disease

Vitamin K2’s biggest role is preventing blood vessel calcification that can lead to the development of cardiovascular disease.

How much vitamin K2 do you need?

You don’t need a lot of vitamin K2 to make a difference. You just need to take enough on a consistent basis to correct and prevent any deficiencies. Since adequate amounts of vitamin K2 can be difficult to get through food on a daily basis, supplementing with 100 to 200 mcg per day can be helpful.

How to get more vitamin K2

Vitamin K2 is fat-soluble and is best taken with vitamin D to help keep your levels from going too high as well as making vitamin D more bioavailable to your body. Take them with a fat-containing meal such as avocado, salmon, or just a bit of butter or coconut oil added to whatever you’re cooking. And if you are looking to get more of this nutrient through food- natto, a Japanese superfood made from non-GMO fermented soybeans is high in K2. Dandelion greens, raw Swiss chard, and cooked kale also contain vitamin K1 which is converted to K2 in a healthy gut microbiome. 

What is the best way to get these nutrients?

The benefits of these two nutrients are unmatched, and when taken together, only amplify their bioavailability. That’s why I believe it is so important to take advantage of vitamin synergy and the motivation behind formulating my supplement The D3-K2.

In my telehealth functional medicine clinic, I have seen firsthand just how difficult it is to get enough of these vital nutrients. I specifically chose the most bioavailable forms of vitamin D and vitamin K2 to ensure you aren’t missing out on any of their important health benefits. Afterall, why take a supplement if it isn’t going to give you the results you desire for your health?

Supplementing with Vitamin D3 has been shown in multiple studies to be twice as likely to raise vitamin D levels than other forms of vitamin D. (6) And when choosing a K2, I personally curated The D3-K2 with menaquinone-7 (MK-7), a highly bioavailable and bioactive form of K2, to balance hormones and enhance absorption of vitamin D.

So, as we hit the mid-winter slump, it’s more important than ever to load up on these two nutrients. Not only are these vitamins essential for keeping our immune systems strong during the height of cold and flu season, they can help us fight those winter blues that start to creep in the second the holiday cheer is over.

Instead of waiting until the first sunny day arrives months from now, I want to make it even easier for you to take advantage of this vitamin synergy.

As one of the first functional medicine telehealth clinics in the world, we provide webcam health consultations for people around the globe. 

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  1. Wilkins, Consuelo H et al. “Vitamin D deficiency is associated with low mood and worse cognitive performance in older adults.” The American journal of geriatric psychiatry : official journal of the American Association for Geriatric Psychiatry vol. 14,12 (2006): 1032-40. doi:10.1097/01.JGP.0000240986.74642.7c
  2. Carter, M J et al. “Guidelines for the management of inflammatory bowel disease in adults.” Gut vol. 53 Suppl 5,Suppl 5 (2004): V1-16. doi:10.1136/gut.2004.043372
  3. Simpson, Steve Jr et al. “Higher 25-hydroxyvitamin D is associated with lower relapse risk in multiple sclerosis.” Annals of neurology vol. 68,2 (2010): 193-203. doi:10.1002/ana.22043
  4. Umhau, John C et al. “Low vitamin D status and suicide: a case-control study of active duty military service members.” PloS one vol. 8,1 (2013): e51543. doi:10.1371/journal.pone.0051543
  5. Moriya, Masayuki et al. “Vitamin K2 ameliorates experimental autoimmune encephalomyelitis in Lewis rats.” Journal of neuroimmunology vol. 170,1-2 (2005): 11-20. doi:10.1016/j.jneuroim.2005.08.001
  6. Professor Sue Lanham New and Dr. Laura Pripkovic Daily supplementation with 15 mg vitamin D2 compared with vitamin D3 to increase wintertime 25-hydroxyvitamin D status in healthy South Asian and white European women: a 12-week randomized, placebo-controlled food-fortification trial. American Journal of Clinical Nutrition DOI: AJCN/2016/138693
  7. anxiety. Behav Brain Res. 2004;154(2):577‐584. doi:10.1016/j.bbr.2004.03.026
  8. Crippa JA, Derenusson GN, Ferrari TB, et al. Neural basis of anxiolytic effects of cannabidiol (CBD) in generalized social anxiety disorder: a preliminary report. J Psychopharmacol. 2011;25(1):121‐130. doi:10.1177/0269881110379283
  9. Bergamaschi MM, Queiroz RH, Chagas MH, et al. Cannabidiol reduces the anxiety induced by simulated public speaking in treatment-naïve social phobia patients. Neuropsychopharmacology. 2011;36(6):1219‐1226. doi:10.1038/npp.2011.6
  10. Hill MN, Patel S. Translational evidence for the involvement of the endocannabinoid system in stress-related psychiatric illnesses. Biol Mood Anxiety Disord. 2013;3(1):19. Published 2013 Oct 22. doi:10.1186/2045-5380-3-19

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Dr. Will Cole, DNM, IFMCP, DC is a leading functional medicine expert who consults people around the globe, starting one of the first functional medicine telehealth centers in the world. Named one of the top 50 functional and integrative doctors in the nation, Dr. Will Cole provides a functional medicine approach for thyroid issues, autoimmune conditions, hormonal imbalances, digestive disorders, and brain problems. He is the host of the popular The Art Of Being Well podcast and the New York Times bestselling author of Intuitive Fasting, Ketotarian, The Inflammation Spectrum, and Gut Feelings: Healing the Shame-Fueled Relationship Between What You Eat and How You Feel.

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Gut Feelings

Healing The Shame-Fueled Relationship
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