Two vitamins with many important functions

Both Vitamin D and Vitamin K are fat soluble vitamins, meaning that they can be absorbed by fatty tissues in the body.1

Structure: Certain chemical forms of some vitamins appear to be better absorbed than other forms. This is the case for these vitamins as well: the D3 (cholecalciferol) form of Vitamin D and the K2 (menaquinone) form of Vitamin K are considered to be the better-absorbing forms.2,4,7,8

Sources: Vitamin D is found in some foods including the livers of fatty fish like sardines, mackerel, tuna, and salmon. It is also found in fortified dairy, particularly milk. Best known is the Vitamin D that is available from sun exposure.2,6 Vitamin K is found in green leafy vegetables like kale, spinach, and Swiss chard as well as broccoli and asparagus among others. It is also found in some vegetable oils including soy, olive, and canola. It is also produced by bacteria in the gut.7,8,10

Functions: Once absorbed into the system, each of these vitamins has a number of supporting roles in a variety of cellular activities.

• Bone mineralization is supported by Vitamin D and Vitamin K. Vitamin D in particular supports calcium absorption and utilization. This is important for bone growth and tooth integrity.3,4,5Vitamin K is important for bone metabolism.7,8
• Cellular activity is influenced both as well. Vitamin D is known for its role in cell differentiation, the process by which cells develop into specialized forms such as a thyroid cell or nerve cell.5 Vitamin K is important for cell proliferation, which is the growth of new cells.9
• Immune function is also supported by both vitamins. Vitamin D is known as an immune system modulator.5 Vitamin K supports the growth of all cell types including immune system cells.9
• Blood clotting is supported by Vitamin D and Vitamin K.4,7,8

1 http://www.ext.colostate.edu/pubs/foodnut/09315.html
2 http://www.medscape.com/viewarticle/589256_4
3 Handbook of Vitamins, Lawrence J. Machlin, pg. 68-69 1984, Marcel Dekker, Inc
4 http://orthomolecular.org/nutrients/vitamins.shtml
5 http://lpi.oregonstate.edu/infocenter/vitamins/vitaminD/
6 http://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/#h3
7 http://orthomolecular.org/nutrients/vitamins.shtml
8 http://www.vitamins-supplements.org/vitamin-K.php
9 http://lpi.oregonstate.edu/infocenter/vitamins/vitaminK/
10 http://lpi.oregonstate.edu/infocenter/vitamins/vitaminK/index.html#food_source

These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.