Vitamin D Total

Why is Vitamin D important for your Healthspan?

‍Vitamin D levels are fundamental for maintaining skeletal integrity and supporting overall physiological resilience, which are important for Healthspan. Adequate Vitamin D is crucial for proper calcium absorption, directly contributing to strong bones and helping to prevent conditions like osteoporosis. Beyond bone health, it plays a role in immune system regulation, muscle function, and modulating inflammation. Insufficient levels are widespread and can contribute to bone fragility, increased susceptibility to infections, and are associated with a higher risk of various chronic diseases, impacting long-term vitality and disease prevention.

‍What is Vitamin D?

Vitamin D is a fat-soluble vitamin that functions more like a steroid hormone within the body. While it can be obtained from certain foods and supplements, its primary natural source is exposure of the skin to sunlight (specifically UVB radiation), which triggers its synthesis. Once synthesized or ingested, Vitamin D is converted in the liver to 25-hydroxyvitamin D [25(OH)D], which is the main form measured in blood to assess a person's Vitamin D status. This 25(OH)D is then further converted in the kidneys into its most active form, 1,25-dihydroxyvitamin D. Vitamin D's most well-known function is regulating calcium and phosphate levels in the body, which is essential for bone mineralization and maintaining strong bones. However, receptors for Vitamin D are found on cells throughout nearly every tissue and organ, indicating its widespread roles in immune modulation, cell growth, muscle function, and reducing inflammation.

‍How do we take action?

To maintain healthy Vitamin D levels, one should aim for sensible sun exposure, though this varies by geography, skin type, and time of year. Dietary sources include fatty fish (salmon, mackerel, tuna), fish liver oils, and fortified foods like milk and cereals. Given that sun exposure alone is often insufficient, particularly in regions like Canada, supplementation with Vitamin D3 is frequently recommended. If levels are found to be deficient or insufficient, a healthcare provider can advise on appropriate dosing for supplementation. Regular monitoring of Vitamin D levels helps ensure optimal status and supports long-term bone health, immune function, and overall Healthspan.

‍Additional Sources

1. Christakos, S., Ajibade, D. V., Dhawan, P., Fechner, A. J., & Mady, L. J. (2010). Vitamin D: metabolism. Endocrinology and metabolism clinics of North America, 39(2), 243–253. https://doi.org/10.1016/j.ecl.2010.02.002

2. Bouillon, R., Carmeliet, G., Verlinden, L., van Etten, E., Verstuyf, A., Luderer, H. F., Lieben, L., Mathieu, C., & Demay, M. (2008). Vitamin D and human health: lessons from vitamin D receptor null mice. Endocrine reviews, 29(6), 726–776. https://doi.org/10.1210/er.2008-0004

3. Biancuzzo, R. M., Clarke, N., Reitz, R. E., Travison, T. G., & Holick, M. F. (2013). Serum concentrations of 1,25-dihydroxyvitamin D2 and 1,25-dihydroxyvitamin D3 in response to vitamin D2 and vitamin D3 supplementation. The Journal of clinical endocrinology and metabolism, 98(3), 973–979. https://doi.org/10.1210/jc.2012-2114

4. Tripkovic, L., Lambert, H., Hart, K., Smith, C. P., Bucca, G., Penson, S., Chope, G., Hyppönen, E., Berry, J., Vieth, R., & Lanham-New, S. (2012). Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. The American journal of clinical nutrition, 95(6), 1357–1364. https://doi.org/10.3945/ajcn.111.031070

5. Institute of Medicine (US) Committee to Review Dietary Reference Intakes for Vitamin D and Calcium; Ross AC, Taylor CL, Yaktine AL, et al., editors. Dietary Reference Intakes for Calcium and Vitamin D. Washington (DC): National Academies Press (US); 2011. 3, Overview of Vitamin D. Available from: https://www.ncbi.nlm.nih.gov/books/NBK56061/

6. Christakos, S., Dhawan, P., Porta, A., Mady, L. J., & Seth, T. (2011). Vitamin D and intestinal calcium absorption. Molecular and cellular endocrinology, 347(1-2), 25–29. https://doi.org/10.1016/j.mce.2011.05.038

7. Hossein-nezhad, A., & Holick, M. F. (2013). Vitamin D for health: a global perspective. Mayo Clinic proceedings, 88(7), 720–755. https://doi.org/10.1016/j.mayocp.2013.05.011

8. Kinuta, K., Tanaka, H., Moriwake, T., Aya, K., Kato, S., & Seino, Y. (2000). Vitamin D is an important factor in estrogen biosynthesis of both female and male gonads. Endocrinology, 141(4), 1317–1324. https://doi.org/10.1210/endo.141.4.7403

9. Wang, Y., Becklund, B. R., & DeLuca, H. F. (2010). Identification of a highly specific and versatile vitamin D receptor antibody. Archives of biochemistry and biophysics, 494(2), 166–177. https://doi.org/10.1016/j.abb.2009.11.029

10. Ceglia L. (2009). Vitamin D and its role in skeletal muscle. Current opinion in clinical nutrition and metabolic care, 12(6), 628–633. https://doi.org/10.1097/MCO.0b013e328331c707

11. Erem, S., Atfi, A., & Razzaque, M. S. (2019). Anabolic effects of vitamin D and magnesium in aging bone. The Journal of steroid biochemistry and molecular biology, 193, 105400. https://doi.org/10.1016/j.jsbmb.2019.105400

12. Forrest, K. Y., & Stuhldreher, W. L. (2011). Prevalence and correlates of vitamin D deficiency in US adults. Nutrition research (New York, N.Y.), 31(1), 48–54. https://doi.org/10.1016/j.nutres.2010.12.001

13. Schwalfenberg, G. K., Genuis, S. J., & Hiltz, M. N. (2010). Addressing vitamin D deficiency in Canada: a public health innovation whose time has come. Public health, 124(6), 350–359. https://doi.org/10.1016/j.puhe.2010.03.003

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