Vitamin D 25-OH testing and monitoring

Most cells have vitamin D receptors, accounting for the wide-ranging influence of vitamin D on organs and biological systems including the immune, endocrine, and cardiovascular systems.1-4 Not surprisingly, serum vitamin D levels are increasingly regarded as a biomarker of overall health as broad-based screening and monitoring become common. Worldwide an estimated 1 billion people are either vitamin D deficient or insufficient. 5 This emphasizes the need for promptly identifying and adequately treating this common vitamin deficiency.

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Vitamin D 25-OH Overview

Many chronic health conditions have an underlying common denominator of vitamin D insufficiency. Testing for vitamin D insufficiency or deficiency can reveal an association with chronic disease (like cardiovascular conditions and diabetes) and potential health risks of impaired bone health, muscle strength in otherwise healthy individuals.2, 6, 7

One of the better-known roles of (active) vitamin D is maintaining calcium and phosphorus absorption and balance as well as playing an active role in bone tissue maintenance and neuromuscular function. 2, 6

Testing and monitoring vitamin D levels represents a valuable clinical tool that may identify underlying deficiencies. Vitamin D status is a vital component of your patients clinical picture.

Who Should Test

  • Patients with limited exposure to sunlight (indoor living, hospitalization, seasonal exposure)
  • Patients over 60 years of age
  • Patients with chronic conditions especially cardiovascular disease, diabetes, osteomalacia, osteoporosis
  • Neurological conditions e.g. multiple sclerosis, cognitive decline 8, 9
  • Metabolic disorders e.g. diabetes mellitus (type I, type II, GDM) 8, 10
  • Cardiovascular diseases e.g. atherosclerosis, coronary artery disease 11, 12
  • Gastrointestinal disorders e.g. inflammatory bowel disease 13
  • Cancer e.g. colon, breast, prostate and others 8, 14
  • Respiratory conditions e.g. asthma, wheezing 15
  • Skin disorders e.g. eczema, psoriasis, urticarial 8, 16
  • Musculoskeletal disorders e.g. rheumatoid arthritis, musculoskeletal pain, osteoporosis 6, 8
  • Autoimmune disorders e.g. systemic lupus erythematosus (SLE), HIV 17, 18

Test the right form of Vitamin D

Serum prohormone 25(OH)D3 (cholecalciferol) most accurately reflects vitamin D status in the body since 25(OH)D3 is a storage protein of vitamin D and it represents the longer term vitamin D supply (lasts 3-4 months).2, 19 Production and regulation of the physiological active hormone 1,25(OH)2D3 (calcitriol) is tightly controlled and serum levels may not reflect deficiency until it is severe. Therefore, general monitoring of active 1,25(OH)2D3 levels is not recommended.19, 20

About our lab

Cell Science Systems, Corp. is a specialty clinical laboratory that develops and performs laboratory testing in immunology and cell biology supporting the personalized treatment and prevention of chronic disease. Cell Science Systems, Corp. operates a CLIA certified laboratory and is an FDA inspected and registered, cGMP medical device manufacturer meeting ISO EN13485 2012 standards.

Committed to quality

Cell Science Systems fulfills high quality standards in accordance with state, federal and international regulations.

  • CLIA-ID#10D0283906
  • CE Marked. TUV Certified and safety monitored
  • Supported by the EU and the State of Brandenburg
  • ISO 13485:2003 + AC:2012

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1 Holick MF. Vitamin D deficiency. N Engl J Med. 2007 Jul 19;357(3):266-81.

2 Alshahrani F, Aljohani N. Vitamin D: deficiency, sufficiency and toxicity. Nutrients. 2013 Sep 13;5(9):3605-16.

3 Kennel KA, Drake MT, Hurley DL. Vitamin D deficiency in adults: when to test and how to treat. Mayo Clin Proc. 2010 Aug;85(8):752-7

4 Linus Pauling Institute Micronutrient Center. OSU. Vitamin D. Updated July 2014. Accessed April 22, 2015.

5 Norman AW. From vitamin D to hormone D: fundamentals of the vitamin D endocrine system essential for good health. Am J Clin Nutr. 2008 Aug;88(2):491S-499S.

6 Holick MF. Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease. Am J Clin Nutr 2004;80:1678S-1688S.

7 Grant WB, Holick MF. Benefits and requirements of vitamin D for optimal health: a review. Altern Med Rev. 2005 Jun;10(2):94-111.

8 Schwalfenberg G. Not enough vitamin D - Health consequences for Canadians. Can Fam Physician. May 2007;53(5): 841–854.

9 Toffanello ED, Coin A, Perissinotto E, Zambon S, Sarti S, Veronese N, De Rui M, Bolzetta F, Corti MC, Crepaldi G, Manzato E, Sergi G. Vitamin D deficiency predicts cognitive decline in older men and women: The Pro.V.A. Study. Neurology. 2014 Nov 5. pii: 10.

10 Arnold DL, Enquobahrie DA, Qiu C, Huang J, Grote N, VanderStoep A, Williams MA. Early pregnancy maternal vitamin d concentrations and risk of gestational diabetes mellitus. Paediatr Perinat Epidemiol. 2015 May;29(3):200-10.

11 Syal SK, Kapoor A, Bhatia E, Sinha A, Kumar S, Tewari S, Garg N, Goel PK. Vitamin D deficiency, coronary artery disease, and endothelial dysfunction: observations from a coronary angiographic study in Indian patients. J Invasive Cardiol. 2012 Aug;24(8):385-9.

12 Menezes AR, Lamb MC, Lavie CJ, DiNicolantonio JJ. Vitamin D and atherosclerosis. Curr Opin Cardiol. 2014 Nov;29(6):571-7.

13 Mouli VP, Ananthakrishnan AN. Review article: vitamin D and inflammatory bowel diseases. Aliment Pharmacol Ther. 2014 Jan;39(2):125-36.

14 Klampfer L. Vitamin D and colon cancer. World J Gastrointest Oncol. 2014 Nov 15;6(11):430-7.

15 Bener A, Ehlayel MS, Bener HZ, Hamid Q. The impact of Vitamin D deficiency on asthma, allergic rhinitis and wheezing in children: An emerging public health problem. J Family Community Med. 2014 Sep;21(3):154-61.

16 Boonpiyathad T, Pradubpongsa P, Sangasapaviriya A. Vitamin d supplements improve urticaria symptoms and quality of life in chronic spontaneous urticaria patients: a prospective case-control study. Dermatoendocrinol. 2014 Jul 16;6:e29727.

17 Coussensa AK, Naudeb CE, Goliatha R, Chaplin G, Wilkinson RJ, Jablonski RG. High-dose vitamin D3reduces deficiency caused by low UVB exposure and limits HIV-1 replication in urban Southern Africans. Proc Natl Acad Sci U S A. 2015 Jun 30;112(26):8052-7.

18 Yap KS, Northcott M, Hoi AB, Morand EF, Nikpour M. Association of low vitamin D with high disease activity in an Australian systemic lupus erythematosus cohort. Lupus Sci Med. 2015 Apr 8;2(1):e000064.

19 Zittermann A, Prokop S. The role of vitamin D for cardiovascular disease and overall mortality. Adv Exp Med Biol. 2014;810:106-19.

20 National Institutes of Health Office of Dietary Supplements. Vitamin D Fact Sheet for Health Professionals. Accessed April 22, 2015.