Vitamin D, 25-Hydroxy
Vitamin D is critical for maintaining healthy levels of calcium and phosphorus by aiding in their absorption from the gut. This helps the body form and maintain strong bones. Vitamin D also modulates neuromuscular, immune, and other cellular functions. Vitamin D deficiency, as defined by the Endocrine Society, is common. As much as 68% to 77% of the population is estimated to have suboptimal (<30 ng/mL) levels of vitamin D.
Alternate names: 25 OH Vitamin D,Vitamin D, 25-OH,25-Hydroxy Vitamin D,Vitamin D, 25-Hydroxy
- Vitamin D, 25-Hydroxy, Total
Methodology: Immunoassay (IA)
Fasting: Fasting is preferred, but not required.
Water: Drink plenty of water to stay well hydrated.
Medications: Take all medications as prescribed.
Dietary supplements: If you take a dietary supplement containing Vitamin D, discontinue the dietary supplement 48 hours (two days) prior to the blood test. This will give a more realistic picture of a person’s Vitamin D status.
3-4 business days
Result turnaround times are estimates and not guaranteed. Due to factors outside of our control, such as weather, holidays, confirmation/repeat testing or equipment maintenance, our lab may require additional time to complete tests.
Measurement of serum 25-OH vitamin D concentrations provide a good index of circulating vitamin D activity in patients not suffering from renal (kidney) disease. Lower than normal 25-OH vitamin D levels can result from a dietary deficiency, poor absorption of the vitamin or impaired metabolism of the sterol in the liver.
Conditions associated with Vitamin D deficiency include:
- Back pain
- Breast Cancer
- Colon Cancer
- Congestive heart failure
- Heart attacks
- Insulin resistance
- Menopausal symptoms: vaginal atrophy
- Menstrual Migraines
- Multiple Sclerosis
- Musculoskeletal pain
- Osteomalacia and Rickets
- Ovarian Cancer
- Pancreatic Cancer
- Polycystic Ovary Syndrome (PCOS)
- Prostate Cancer
- Rheumatoid arthritis
- Seasonal Affective Disorder (SAD)
- Type I Diabetes (Insulin Dependent)
- Type II Diabetes (Non-Insulin Dependent)
The Endocrine Society recommends regular screening for individuals at risk for deficiency. These include people who have:
- Osteomalacia and rickets
- Chronic kidney disease
- Diseases that require certain medications (anti-seizure medications, glucocorticoids, AIDS medications, antifungals, cholestyramine)
- Malabsorption syndromes, including inflammatory bowel disease, Crohn’s disease, cystic fibrosis, history of bariatric surgery
- Hepatic failure
Screening is also recommended for:
- African American and Hispanic children and adults
- Pregnant and lactating women
- Older adults with a history of falls
- Older adults with history of nontraumatic fractures
- Obese children
- Obese adults
Above normal levels of vitamin D can lead to elevated calcium in the blood, called hypercalcemia.
Al Faraj S, Al Mutairi K. Vitamin D deficiency and chronic low back pain in Saudi Arabia. Spine. 2003 Jan 15;28(2):177-9.
Brunvand L, Haga P, Tangsrud SE, et al. Congestive heart failure caused by vitamin D deficiency? Acta Paediatr. 1995 Jan;84(1):106-8.
Chiu KC, Chu A, Go VL, Saad MF. Hypovitaminosis D is associated with insulin resistance and beta cell dysfunction. Am J Clin Nutr. 2004 May;79(5):820-5.
Daniele ND, Carbonelli MG, Candeloro N, et al. Effect of supplementation of calcium and Vitamin D on bone mineral density and bone mineral content in peri- and post-menopause women; A double-blind, randomized, controlled trial. Pharmacol Res. 2004 Dec;50(6):637-41.
Gambichler T, Bader A, Vojvodic M, et al. Impact of UVA exposure on psychological parameters and circulating serotonin and melatonin. BMC Dermatol. 2002 Apr 12;2(1):6.
Garland CF, Garland FC, Gorham ED. Can colon cancer incidence and death rates be reduced with calcium and vitamin D? Am J Clin Nutr. 1991 Jul;54(1 Suppl):193S-201S.
Garland CF, Garland FC. Do sunlight and vitamin D reduce the likelihood of colon cancer? Int J Epidemiol. 1980 Sep;9(3):227-31.
Ginde AA, Liu MC, Camargo CA, et al. Demographic differences and trends of vitamin D insufficiency in the US population, 1988–2004. Arch Intern Med. 2009;169:626-632.
Grant WB. An ecologic study of dietary and solar ultraviolet-B links to breast carcinoma mortality rates. Cancer. 2002 Jan 1;94(1):272-81.
Hanchette CL, Schwartz GG. Geographic patterns of prostate cancer mortality. Evidence for a protective effect of ultraviolet radiation. Cancer. 1992 Dec 15;70(12):2861-9.
Holick MF, Binkley NC, Bischoff-Ferrari HA, et al. Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrin Metab. 2011;96:1911-1930.
Holick MF, 2007 Vitamin D deficiency. N Engl J Med. 2017:357:266-281.
Hypponen E, Laara E, Reunanen A, et al. Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study. Lancet. 2001 Nov 3;358(9292):1500-3.
Inomata S, Kadowaki S, Yamatani T, et al. Effect of 1 alpha (OH)-vitamin D3 on insulin secretion in diabetes mellitus. Bone Miner. 1986 Jun;1(3):187-92.
Kumar J, Muntner P, Kaskel FJ, et al. Prevalence and associations of 25-hydroxyvitamin D deficiency in US children: NHANES 2001–2004. Pediatrics. 2009;124:e362-e370.
Lai JK, Lucas RM, Clements MS, et al. Assessing vitamin D status: pitfalls for the unwary. Mol Nutr Food Res. 2010;54:1062-1071.
Lansdowne AT, Provost SC. Vitamin D3 enhances mood in healthy subjects during winter. Psychopharmacology (Berl). 1998 Feb;135(4):319-23.
Luscombe CJ, Fryer AA, French ME, Liu S, Saxby MF, Jones PW, Strange RC. Exposure to ultraviolet radiation: association with susceptibility and age at presentation with prostate cancer. Lancet. 2001 Aug 25;358(9282):641-2.
Mascarenhas R, Mobarhan S. Hypovitaminosis D-induced pain. Nutr Rev. 2004 Sep;62(9):354-9.
Merlino, L. A. et al. Vitamin D intake is inversely associated with rheumatoid arthritis. Arthritis and Rheumatism, 50, 72 - 77, (2004).
Miettinen S, Ahonen MH, Lou YR, et al. Role of 24-hydroxylase in vitamin D3 growth response of OVCAR-3 ovarian cancer cells. Int J Cancer. 2004 Jan 20;108(3):367-73.
Munger KL, Zhang SM, O'Reilly E, et al. Vitamin D intake and incidence of multiple sclerosis. Neurology. 2004 Jan 13;62(1):60-5.
Papadimitropoulos E, Wells G, Shea B, et al. Meta-analyses of therapies for postmenopausal osteoporosis. VIII: Meta-analysis of the efficacy of vitamin D treatment in preventing osteoporosis in postmenopausal women. Endocr Rev. 2002 Aug;23(4):560-9.
Pfeifer M, Begerow B, Minne HW, Nachtigall D, Hansen C. Effects of a short-term vitamin D(3) and calcium supplementation on blood pressure and parathyroid hormone levels in elderly women. J Clin Endocrinol Metab. 2001 Apr;86(4):1633-7.
Plotnikoff GA , Quigley JM. Prevalence of severe hypovitaminosis D in patients with persistent, nonspecific musculoskeletal pain. Mayo Clin Proc. 2003 Dec;78(12):1463-70.
Ross AC, Manson JE, Abrams SA, et al. The 2011 report on dietary reference intakes for calcium and vitamin D from the Institute of Medicine: what clinicians need to know. J Clin Endocrin Metab. 2011;96:53-58.
Schwartz GG, Eads D, Rao A, et al. Pancreatic cancer cells express 25-hydroxyvitamin D-1 alpha-hydroxylase and their proliferation is inhibited by the prohormone 25-hydroxyvitamin D3. Carcinogenesis. 2004 Jun;25(6):1015-26. Epub 2004 Jan 23.
Scragg R, Jackson R, Holdaway IM, et al. Myocardial infarction is inversely associated with plasma 25-hydroxyvitamin D3 levels: a community-based study. Int J Epidemiol. 1990 Sep;19(3):559-63.
Thys-Jacobs S, Donovan D, Papadopoulos A, et al. Vitamin D and calcium dysregulation in the polycystic ovarian syndrome. Steroids. 1999 Jun;64(6):430-5.
Thys-Jacobs S. Alleviation of migraines with therapeutic vitamin D and calcium. Headache. 1994 Nov-Dec;34(10):590-2.
Thys-Jacobs S. Vitamin D and calcium in menstrual migraine. Headache. 1994 Oct;34(9):544-6.
Yildirim B, Kaleli B, Duzcan E, et al. The effects of postmenopausal Vitamin D treatment on vaginal atrophy. Maturitas. 2004 Dec 10;49(4):334-7.
Zittermann A, Schleithoff SS, Tenderich G, et al. Low vitamin D status: a contributing factor in the pathogenesis of congestive heart failure? J Am Coll Cardiol. 2003 Jan 1;41(1):105-12.
Zittermann A. Vitamin D in preventive medicine: are we ignoring the evidence? Br J Nutr. 2003 May;89(5):552-72.