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Best Vitamin D Supplement

Vitamin D3™

Vitamin D3™



Immune, Bone, & Joint Support







Vitamin D3, cholecalciferol, is one of the 4 essential fat-soluble vitamins. It is the active form of vitamin D, which means that it is the only type of vitamin D that will be able to work appropriately within the body. Vitamin D has a cholesterol-based structure and acts more similar to a hormone than a vitamin, despite the name.


  • Vitamin D, along with calcium, plays a significant role in maintaining bone mineral density.*
  • Vitamin D is being researched for its ability to reduce risk of certain types of cancer.*
  • The signaling effects of vitamin D may enhance testosterone synthesis and reduce fat mass.*


With wide-reaching health implications, vitamin D has become a hot topic – specifically in regards to what the optimal levels of vitamin D intake may be. Agencies, such as the Institute of Medicine and the Endocrine Society, are at odds over the necessary amount of Vitamin D. At the upper end, the desired blood levels are attained with a supplemental dose of 5,000 IU – the exact amount contained in Vitamin D3™.


*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Supplement Facts

 Best Vitamin D Supplement

Ingredient Profile

Vitamin D3

Vitamin D is a fat-soluble vitamin that may improve cognition, immunity, bone health, and quality of life. It is produced in the skin when activated by sunlight, but most individuals must obtain the majority of Vitamin D via their diet.


  • Aids in calcium absorption and reduction of falls for improved bone health
  • Low vitamin D status is associated with seasonal cold and flu outbreaks
  • Vitamin D metabolites strengthen muscle contractions
  • May help reduce and control blood pressure
  • Improves mood and nervous system health
  • May support a healthy appetite
  • Enhances sex-hormone synthesis

Q: What is the best way to take Vitamin D3™?

A: As a dietary supplement, take 1 serving (1 softgel) once daily with food.


Q: I live in the northern half of the United States. Should I supplement vitamin D?

A: Yes. Supplementation may not be needed during the summer depending on your sunlight exposure, but anyone above 37 degrees latitude is producing little to no vitamin D from sun exposure. The 37th parallel is right about at the top of Virginia and Texas and just south of San Francisco California. Even those in the southern states should consider vitamin D supplementation if their sun exposure is limited.


Q: Can I take Vitamin D3™ with any other Optitune products?

A: Yes, for joint and bone health, stack with Ultra Cissus™.


Vitamin D3

  1. Littlejohns, T. J., Henley, W. E., Lang, I. A., Annweiler, C., Beauchet, O., Chaves, P. H., ... & Lopez, O. L. (2014). Vitamin D and the risk of dementia and Alzheimer disease. Neurology, 83(10), 920-928.
  2. Spedding, S. (2014). Vitamin D and depression: a systematic review and meta-analysis comparing studies with and without biological flaws. Nutrients, 6(4), 1501-1518.
  3. Burgaz, A., Orsini, N., Larsson, S. C., & Wolk, A. (2011). Blood 25-hydroxyvitamin D concentration and hypertension: a meta-analysis. Journal of hypertension, 29(4), 636-645.
  4. Gordan, R., Gwathmey, J. K., & Xie, L. H. (2015). Autonomic and endocrine control of cardiovascular function. World journal of cardiology, 7(4), 204.
  5. Ceglia, L. (2009). Vitamin D and its role in skeletal muscle. Current opinion in clinical nutrition and metabolic care, 12(6), 628.
  6. Bischoff-Ferrari, H. A., Dawson-Hughes, B., Willett, W. C., Staehelin, H. B., Bazemore, M. G., Zee, R. Y., & Wong, J. B. (2004). Effect of vitamin D on falls: a meta-analysis. Jama, 291(16), 1999-2006.
  7. Cannell, J. J., Vieth, R., Umhau, J. C., Holick, M. F., Grant, W. B., Madronich, S., ... & Giovannucci, E. (2006). Epidemic influenza and vitamin D. Epidemiology & Infection, 134(6), 1129-1140.
  8. Pilz, S., Frisch, S., Koertke, H., Kuhn, J., Dreier, J., Obermayer-Pietsch, B., ... & Zittermann, A. (2011). Effect of vitamin D supplementation on testosterone levels in men. Hormone and Metabolic Research, 43(3), 223.

California’s Proposition 65 entitles California consumers to special warnings.

WARNING: Cancer and Reproductive Harm -