The Vitamin D3 + K2 Combo Is Powerful!
- Nov 20, 2018
- Kelly Harrington, MS, RDN
It’s common knowledge vitamin D is known as the sunshine vitamin because it's produced in the skin upon exposure to sunlight. But if you’re not getting much sun, such as during the cold winter months, or you regularly cover up or wear sunscreen, are you getting enough vitamin D? The answer is a resounding “Probably not!”
Recent research suggests we need much more vitamin D than previously thought for optimal immune function and long-term health. But first...
What Does Vitamin D Do?
Cholecalciferol, also known as vitamin D3, is more biologically active in the body than vitamin D2.
- Vitamin D increases calcium absorption from the intestinal tract (bone health).
- Vitamin D reduces calcium losses in urine (bone health).
- Vitamin D mobilizes calcium from bone to maintain normal blood calcium levels (bone health).
- Vitamin D deficiency has recently been associated with immune function, cardiovascular health, depression, inflammatory bowel disease, osteoporosis and hormone balance.
- Along with vitamin A and thyroid hormone, vitamin D regulates the DNA of some cells to favor maturation into specific cell types. This is important in orchestrating tissue development in the fetus and growing child.
How Does Vitamin K Benefit Vitamin D?
Studies now show Vitamin K greatly enhances the benefits of vitamin D, in terms of bone strength and cardiovascular health. Vitamin D supports bone health by helping with calcium absorption. However, it is vitamin K that directs calcium to your skeleton, to prevent it from being deposited in the wrong areas.
Several different forms of vitamin K exist, with the primary form being vitamin K1, or phylloquinone, found primarily in green vegetables. Another form of vitamin K, known as vitamin K2 or menaquinone, is found primarily in animal products such as meat or eggs, as well as in foods such as cheese and natto, a fermented soy product. While most of the benefits of vitamin K were previously attributed to vitamin K1, recent research has identified important benefits for vitamin K2.
How Much D3 + K2 Do You Need?
Scientists don't yet know the optimal daily dose of vitamin D, and recommendations vary depending on who you ask. Here are recs for adults from three different entities.
The Vitamin D Council recommends 5,000 IU/day
The Food and Nutrition Board recommends 600-800 IU/day
The Endocrine Society recommends 1,500-2,000 IU/day
One thing to know is it takes a lot of vitamin D to develop a toxicity—40,000 IU per day for a couple of months or longer, or a very large one-time dose. A good starting point is to test your vitamin D levels, and adjust your dosage based off the results.
Regarding vitamin K2, studies show an amount of 180 to 200 micrograms should be enough to activate your body's K2-dependent proteins to shuttle the calcium where it needs to be, and remove it from the places where it shouldn't.
Consider a combo vitamin D3 + K2 supplement to ensure your body's getting enough of what it needs.
In Health and Happiness,
Kelly Harrington, MS, RDN
Registered Dietitian Nutritionist for Healthy Goods
References
1. Vitamin D Council. Health Conditions.
2. Kjaergaard M, Waterloo K, Wang K etc al. Effects of Vitamin D supplement on depression scores in people with low levels of serum 25-hydroxyvitamin D: nested case-control study and randomised trial. Br J Psychiatry. 2012 Jul 12.
3. Avenell A, Gillespie WJ, Gillespie LD, O’connell D. Vitamin D and vitamin D analogues for preventing fractures associated with involutional and post-menopausal osteoporosis. Cochrane Database Syst Rev. 2009;(2):CD000227.
4. Vitamin D Council. How do I get the vitamin D my body needs?
5. Vitamin K Fact Sheet for Health Professionals.
