Health is better at serum 25(OH)D above 30ng/mL

2011 Holick, 2011, Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society Practice Guideline, Journal of Clinical Endocrinology and Metabolism, 96, 1911, 10.1210/jc.2011-0385 Holick, 2006, High prevalence of vitamin D inadequacy and implications for health, Mayo Clinic Proceedings, 81, 353, 10.4065/81.3.353 Holick, 2008, Vitamin D deficiency: a worldwide problem with health consequences, American Journal of Clinical Nutrition, 87, 1080S, 10.1093/ajcn/87.4.1080S Holick, 2011, Health benefits of vitamin D and sunlight: a D-bate, Nature Reviews Endocrinology, 7, 73, 10.1038/nrendo.2010.234 Peterlik, 2005, Vitamin D and calcium deficits predispose for multiple chronic diseases, European Journal of Clinical Investigation, 35, 290, 10.1111/j.1365-2362.2005.01487.x Priemel, 2010, Bone mineralization defects and vitamin D deficiency: histomorphometric analysis of iliac crest bone biopsies and circulating 25-hydroxyvitamin D in 675 patients, Journal of Bone and Mineral Research, 25, 305, 10.1359/jbmr.090728 Heaney, 2003, Calcium absorption varies within the reference range for serum 25-hydroxyvitamin D, Journal of the American College of Nutrition, 22, 142, 10.1080/07315724.2003.10719287 Shapses, 2011, Effect of alendronate and vitamin D3 on fractional calcium absorption in a double-blind, randomized, placebo-controlled trial in postmenopausal osteoporotic women, Journal of Bone and Mineral Research, 26, 1836, 10.1002/jbmr.395 Heaney, 2004, Serum 25-hydroxy-vitamin D and the health of the calcium economy, 227 Bordier, 1978, Vitamin D metabolites and bone mineralization in man, Journal of Clinical Endocrinology and Metabolism, 46, 284, 10.1210/jcem-46-2-284 Barger-Lux, 2002, Effects of above average summer sun exposure on serum 25-hydroxyvitamin D and calcium absorption, Journal of Clinical Endocrinology and Metabolism, 87, 4952, 10.1210/jc.2002-020636 Trivedi, 2003, Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomized double blind controlled trial, British Medical Journal, 326, 469, 10.1136/bmj.326.7387.469 Bischoff-Ferrari, 2009, Fall prevention with supplemental and active forms of vitamin D: a meta-analysis of randomized controlled trials, British Medical Journal, 339, b3692, 10.1136/bmj.b3692 Bischoff-Ferrari, 2005, Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials, Journal of the American Medical Association, 293, 2257, 10.1001/jama.293.18.2257 Bischoff-Ferrari, 2012, A pooled analysis to define vitamin D dose requirements for fracture prevention, New England Journal of Medicine, 367, 40, 10.1056/NEJMoa1109617 Grant, 2005, Oral vitamin D3 and calcium for secondary prevention of low-trauma fractures in elderly people (Randomised Evaluation of Calcium or Vitamin D, RECORD); a randomized placebo-controlled trial, Lancet, 365, 1621, 10.1016/S0140-6736(05)63013-9 Jackson, 2006, Calcium and vitamin D supplementation and the risk of fractures, New England Journal of Medicine, 354, 669, 10.1056/NEJMoa055218 Willett, 1998 Levine, 1997, Trial of calcium to prevent preeclampsia, New England Journal of Medicine, 337, 69, 10.1056/NEJM199707103370201 Chung, 2009, Vitamin D and calcium: a systematic review of health outcomes, Evidence Report Technology Assessment, 183, 1 Whitehouse, 2012, Maternal serum vitamin D levels during pregnancy and offspring neurocognitive development, Pediatrics, 10.1542/peds.2011-2644 Gagnon, 2012, Low serum 25-hydroxyvitamin D is associated with increased risk of the development of the metabolic syndrome at five years: results from a National, Population-Based Prospective Study (The Australian Diabetes, Obesity and Lifestyle Study: AusDiab), The Journal of Clinical Endocrinology and Metabolism, 10.1210/jc.2011-3187 Heaney, 2012, The nutrient problem, Nutrition Reviews, 70, 165, 10.1111/j.1753-4887.2011.00469.x Luxwolda, 2012, Traditionally living populations in East Africa have a mean serum 25-hydroxyvitamin D concentration of 115nmol/L, British Journal of Nutrition, 10.1017/S0007114511007161 Ginde, 2009, Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey, Archives of Internal Medicine, 169, 384, 10.1001/archinternmed.2008.560