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Circulating vitamin D3 and 25-hydroxyvitamin D in humans: An important tool to define adequate nutritional vitamin D status. Hollis BW, Wagner CL, Drezner MK, Binkley NC. J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):631-4. Epub 2007 Jan 10. PMID: 17218096 In the present study, we sought to investigate what circulating 25(OH)D levels would result in populations exhibiting no substrate limitations to the vitamin D-25-hydroxylase. To perform this, we chose two distinct populations. The first were individuals from a year-found sunny environment who spent a good deal of time outdoors. The second were a group of lactating women receiving a substantial daily oral dose of vitamin D3. Surprisingly, a study such as this previously had not been undertaken. There are several reasons for this. First, finding a group of sun-exposed individuals is not an easy task; in fact, we had to go to Hawaii to find them. Secondly, very few studies have been performed where subjects actually received adequate vitamin D3 supplementation to make them replete. Finally, it is very difficult and costly to measure circulating vitamin D3 and relate it to circulating 25(OH)D. The results of our study are far-reaching. This study also demonstrates that individuals can be vitamin D deficient with significant sun exposure if the skin area exposed is limited as was suggested several years ago (19). Finally, whether one receives their vitamin D3 orally or through UV exposure, the vitamin D-25-hydroxylase appears to handle it in an equivalent fashion with respect to maintaining circulating 25(OH)D levels. Thus, we believe that the relationship between circulating vitamin D and 25(OH)D may define adequate nutritional vitamin D status.

Together, the earlier data and the data of Heaney et al indicate that an oral dose of vitamin D2 or vitamin D3 would lead to a comparable increase in circulating 25(OH)D concentrations in children and adults when the initial 25(OH)D3 concentrations in the groups are similar and when equivalent oral vitamin D doses expressed per kilogram body weight/d are given. Serum 25-hydroxyvitamin D response to oral vitamin D intake in children. Zittermann A. Am J Clin Nutr. 2003 Sep;78(3):496-7. PMID: 12936937

Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomised double blind controlled trial. Trivedi DP, Doll R, Khaw KT. BMJ. 2003 Mar 1;326(7387):469. PMID: 12609940 CONCLUSION: Four monthly supplementation with 100 000 IU oral vitamin D may prevent fractures without adverse effects in men and women living in the general community.

Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is limited. Glerup H, Mikkelsen K, Poulsen L, Hass E, Overbeck S, Thomsen J, Charles P, Eriksen EF. J Intern Med. 2000 Feb;247(2):260-8. PMID: 10692090 Conclusions. Severe vitamin D deficiency is prevalent amongst sunlight-deprived individuals living in Denmark. In veiled Arab women, vitamin D deficiency is the result of a combination of limitations in sunlight exposure and a low oral intake of vitamin D. The oral intake of vitamin D amongst veiled ethnic Danish Moslems was, however, very high, at 13.53 µg (approximately 600 IU), but they were still vitamin D-deficient. Our results suggest that the daily oral intake of vitamin D in sunlight-deprived individuals should exceed 600 IU; most probably it should be 1000 IU day-1 to secure a normal level of 25-hydroxyvitamin D. This finding is in contrast with the commonly used RDA (recommended daily allowance) for adults in Europe: 200 IU day-1.

Dietary vitamin D and cancers of the oral cavity and esophagus. Lipworth L, Rossi M, McLaughlin JK, Negri E, Talamini R, Levi F, Franceschi S, La Vecchia C. Ann Oncol. 2009 Sep;20(9):1576-81. Epub 2009 Jun 1. PMID: 19487490 Conclusion: We observed inverse associations between dietary vitamin D intake and risk of SCCE and, perhaps, oral/pharyngeal cancer, which were most pronounced among heavy current smokers and heavy consumers of alcohol.

Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomised double blind controlled trial. Trivedi DP, Doll R, Khaw KT. BMJ. 2003 Mar 1;326(7387):469. PMID: 12609940 Conclusion: Four monthly supplementation with 100 000 IU oral vitamin D may prevent fractures without adverse effects in men and women living in the general community.

Differences in vitamin D status between countries in young adults and the elderly. McKenna MJ. Am J Med. 1992 Jul;93(1):69-77. PMID: 1385673 PURPOSE: To compare vitamin D status between countries in young adults and in the elderly. MATERIALS AND METHODS: Reports on vitamin D status (as assessed by serum 25-hydroxyvitamin D) from 1971 to 1990 were reviewed. Studies were grouped according to geographic regions: North America (including Canada and the United States); Scandinavia (including Denmark, Finland, Norway, and Sweden); and Central and Western Europe (including Belgium, France, Germany, Ireland, The Netherlands, Switzerland, and the United Kingdom). RESULTS: Vitamin D status varies with the season in young adults and in the elderly, and is lower during the winter in Europe than in both North America and Scandinavia. Oral vitamin D intake is lower in Europe than in both North America and Scandinavia. Hypovitaminosis D and related abnormalities in bone chemistry are most common in elderly residents in Europe but are reported in all elderly populations. CONCLUSIONS: The vitamin D status in young adults and the elderly varies widely with the country of residence. Adequate exposure to summer sunlight is the essential means to ample supply, but oral intake augmented by both fortification and supplementation is necessary to maintain baseline stores. All countries should adopt a fortification policy. It seems likely that the elderly would benefit additionally from a daily supplement of 10 micrograms of vitamin D.

High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their infants: a 6-month follow-up pilot study. Wagner CL, Hulsey TC, Fanning D, Ebeling M, Hollis BW. Breastfeed Med. 2006 Summer;1(2):59-70. PMID: 17661565 doi:10.1089/bfm.2006.1.59. Objective: To examine the effect of high-dose maternal vitamin D3 (vitD) supplementation on the nutritional vitD status of breastfeeding (BF) women and their infants compared with maternal and infant controls receiving 400 and 300 IU vitD/day, respectively. Design: Fully lactating women (n = 19) were enrolled at 1-month postpartum into a randomized- control pilot trial. Each mother received one of two treatments for a 6-month study period: 0 or 6000 IU vitD3 plus a prenatal vitamin containing 400 IU vitD3. The infants of mothers assigned to the control group received 300 IU vitD3/day; those infants of mothers in the high-dose group received 0 IU (placebo). Maternal serum and milk vitD and 25(OH)D were measured at baseline then monthly; infant serum vitD and 25(OH)D were measured at baseline, and months 4 and 7. Urinary calcium/creatinine ratios were measured monthly in both mothers and infants. Dietary and BF history and outdoor activity questionnaires were completed at each visit. Changes in skin pigmentation were measured by spectrophotometry. Data were analyzed using chi-square, t-test, and analysis of variance (ANOVA) on an intent-to-treat basis. Conclusion: With limited sun exposure, an intake of 400 IU/day vitamin D3 did not sustain circulating maternal 25(OH)D levels, and thus, supplied only extremely limited amounts of vitamin D to the nursing infant via breast milk. Infant levels achieved exclusively through maternal supplementation were equivalent to levels in infants who received oral vitamin D supplementation. Thus, a maternal intake of 6400 IU/day vitamin D elevated circulating 25(OH)D in both mother and nursing infant.

Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials. Bischoff-Ferrari HA, Willett WC, Wong JB, Giovannucci E, Dietrich T, Dawson-Hughes B. JAMA. 2005 May 11;293(18):2257-64. Review. PMID: 15886381 Conclusions Oral vitamin D supplementation between 700 to 800 IU/d appears to reduce the risk of hip and any nonvertebral fractures in ambulatory or institutionalized elderly persons. An oral vitamin D dose of 400 IU/d is not sufficient for fracture prevention.

High-dose oral vitamin D3 supplementation in the elderly. Bacon CJ, Gamble GD, Horne AM, Scott MA, Reid IR. Osteoporos Int. 2009 Aug;20(8):1407-15. Epub 2008 Dec 20. PMID: 19101755 Sixty-three elderly participants were randomized to three regimens of vitamin D supplementation: a 500,000-IU loading dose; the loading dose plus 50,000 IU/month; or 50,000 IU/month. CONCLUSIONS: Large loading doses of vitamin D(3) rapidly and safely normalize 25OHD levels in the frail elderly. Monthly dosing is similarly effective and safe, but takes 3-5 months for plateau 25OHD levels to be reached.

An estimate of cancer mortality rate reductions in Europe and the US with 1,000 IU of oral vitamin D per day. Grant WB, Garland CF, Gorham ED. Recent Results Cancer Res. 2007;174:225-34. Review. PMID: 17302200

Vitamin D and its major metabolites: serum levels after graded oral dosing in healthy men. Barger-Lux MJ, Heaney RP, Dowell S, Chen TC, Holick MF. Osteoporos Int. 1998;8(3):222-30. PMID: 9797906

Barger-Lux MJ, Heaney RP, Dowell S, Chen TC, Holick MF. Vitamin D and its major metabolites: serum levels after graded oral dosing in healthy men.Osteoporos Int. 1998;8(3):222-30.PMID: 9797906 [PubMed - indexed for MEDLINE]

Grant WB, Garland CF, Gorham ED. An estimate of cancer mortality rate reductions in Europe and the US with 1,000 IU of oral vitamin D per day. Recent Results Cancer Res. 2007;174:225-34. PMID: 17302200 [PubMed - in process]

October 6th, 2008 A study led by researchers at the University of California, San Diego School of Medicine suggests that use of oral Vitamin D supplements bolsters production of a protective chemical normally found in the skin, and may help prevent skin infections that are a common result of atopic dermatitis, the most common form of eczema.

Prevention of nonvertebral fractures with oral vitamin D and dose dependency: a meta-analysis of randomized controlled trials. Bischoff-Ferrari HA, Willett WC, Wong JB, Stuck AE, Staehelin HB, Orav EJ, Thoma A, Kiel DP, Henschkowski J. Arch Intern Med. 2009 Mar 23;169(6):551-61. PMID: 19307517 Conclusion Nonvertebral fracture prevention with vitamin D is dose dependent, and a higher dose should reduce fractures by at least 20% for individuals aged 65 years or older.

Conclusions: Healthy men seem to use 3000-5000 IU cholecalciferol/d, apparently meeting > 80% of their winter cholecalciferol need with cutaneously synthesized accumulations from solar sources during the preceding summer months. Current recommended vitamin D inputs are inadequate to maintain serum 25-hydroxycholecalciferol concentration in the absence of substantial cutaneous production of vitamin D. Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol. Heaney RP, Davies KM, Chen TC, Holick MF, Barger-Lux MJ. Am J Clin Nutr. 2003 Jan;77(1):204-10. Erratum in: Am J Clin Nutr. 2003 Nov;78(5):1047. PMID: 12499343

A randomised comparison of increase in serum 25-hydroxyvitamin D concentration after 4 weeks of daily oral intake of 10 microg cholecalciferol from multivitamin tablets or fish oil capsules in healthy young adults. Holvik K, Madar AA, Meyer HE, Lofthus CM, Stene LC. Br J Nutr. 2007 Sep;98(3):620-5. Epub 2007 Apr 24. PMID: 17456248 We conclude that fish oil capsules and multivitamin tablets containing 10 microg cholecalciferol administered over a 4-week period produced a similar mean increase in s-25(OH)D concentration.

"This website is about Vitamin D and MS Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS), with an uncertain cause. Colleen Hayes and Donald Achaeson have suggested that insufficient sunlight exposure and chronic viral infections might be unrelated environmental risk factors for MS. These risk factors may act synergistically to enable the pathogenic autoimmune response. The prevalence of MS is highest where environmental supplies of vitamin D are lowest. Sunshine enables the production of vitamin D3 (VD3) in the skin. Epidemiological studies have shown that higher vitamin D blood levels are associated with lower risk, less relapses and a slower progression of multiple sclerosis. Higher vitamin D levels can be achieved in part by increased oral intake of VD3. Optimal health requires serum 25 hydroxyvitamin D levels higher than 20 ng/ml (50 nmol/L) P Lips, 40 ng/ml (100 nmol/L) P Heaney or at least 40 ng/ml (100 nmol/L) R Vieth. "

Pharmacokinetics of a single, large dose of cholecalciferol. Ilahi M, Armas LA, Heaney RP. Am J Clin Nutr. 2008 Mar;87(3):688-91. PMID: 1832660 Conclusions: Cholecalciferol (100 000 IU) is a safe, effective, and simple way to increase calcidiol concentrations. The dosing interval should be ≤2 mo to ensure continuous serum calcidiol concentrations above baseline. Our study highlights that 100 000 IU cholecalciferol is a safe, efficient, and cost-effective means to increase calcidiol concentrations in the elderly. From this study we can safely recommend 100 000 IU cholecalciferol dosed every 2 mo in persons with moderate baseline calcidiol concentrations. However, in those persons with baseline calcidiol concentrations < 20 ng/mL, even this large dose will not adequately raise their calcidiol concentrations.