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Assessment of dietary vitamin D requirements during pregnancy and lactation. Hollis BW, Wagner CL. Am J Clin Nutr. 2004 May;79(5):717-26. Review. PMID: 15113709 We found that high-dose maternal vitamin D supplementation not only improves the nutritional vitamin D status of breastfeeding infants but also elevates the maternal concentrations into the mid-normal range. Thus, a dual benefit is achieved from high-dose maternal supplementation. It is noteworthy that in the Finnish study, the authors added a disclaimer, "A sufficient supply of vitamin D to the breastfed infant is achieved only by increasing the maternal supplementation up to 2000 IU/d. Such a dose is far higher than the RDA [DRI] for lactating mothers [and therefore] its safety over prolonged periods is not known and should be examined by further study." This point of concern was valid when this study was conducted in 1986 (92); however, on the basis of the current findings of Vieth et al (2) and of Heaney et al (3)-which showed that vitamin D intakes <= 10 000 IU/d (250 µg) are safe for prolonged periods (up to 5 mo)-we believe that it is time to reexamine the understated DRI of vitamin D for lactating mothers. This work is now being conducted in our clinics and laboratory.

Vitamin D supplementation during Antarctic winter. Smith SM, Gardner KK, Locke J, Zwart SR. Am J Clin Nutr. 2009 Apr;89(4):1092-8. Epub 2009 Feb 18. PMID: 19225122 doi:10.3945/ajcn.2008.27189

Vieth R, Choo R, Deboer L, Danjoux C, Morton GC, Klotz L. \nRise in prostate-specific antigen in men with untreated low-grade prostate cancer is slower during spring-summer.\nAm J Ther. 2006 Sep-Oct;13(5):394-9.\nPMID: 16988533 [PubMed - indexed for MEDLI

Vitamin D and depressive symptoms in women during the winter: a pilot study. Shipowick CD, Moore CB, Corbett C, Bindler R. Appl Nurs Res. 2009 Aug;22(3):221-5. PMID: 19616172 doi:10.1016/j.apnr.2007.08.001 ESULTS: Vitamin D supplementation was associated not only with an increase in the serum D levels by an average of 27 ng/ml but also with a decline in the BDI-II scores of an average of 10 points. DISCUSSION: This study suggests that supplemental vitamin D3 reduces depressive symptoms.

Estimation of the dietary requirement for vitamin D in free-living adults >=64 y of age. Cashman KD, Wallace JM, Horigan G, Hill TR, Barnes MS, Lucey AJ, Bonham MP, Taylor N, Duffy EM, Seamans K, Muldowney S, Fitzgerald AP, Flynn A, Strain JJ, Kiely M. Am J Clin Nutr. 2009 May;89(5):1366-74. Epub 2009 Mar 18. PMID: 19297462 doi:10.3945/ajcn.2008.27334 Conclusion: To ensure that the vitamin D requirement is met by the vast majority (>97.5%) of adults aged ≥64 y during winter, between 7.9 and 42.8 µg vitamin D/d is required, depending on summer sun exposure and the threshold of adequacy of 25(OH)D. .

Statins and vitamin D. Aloia JF, Li-Ng M, Pollack S. Am J Cardiol. 2007 Oct 15;100(8):1329. Epub 2007 Jul 5. No abstract available. PMID: 17920383 A total of 208 women were randomized to receive vitamin D3 (n=104) or placebo (n=104). 51 women were on statins. At baseline, the subjects on statins had a significantly higher 25-OHD level than the subjects who were not on statins (51.2 ± 20.1 nmol/L versus 43.2 ± 18.0 nmol/L respectively, p=0.008). This was also true when averaging 25-OHD levels across the 3-year study period and looking at active and placebo patients separately. 185 subjects had follow-up 25-OHD levels drawn every 6 months during the study. Higher levels were seen in the statin use subgroup whether they were on placebo or active vitamin D (Figure 1Figure 1). There was no interaction seen between vitamin D use and statin use, i.e. the impacts are additive (p=0.5502). This significant difference is comparable to the increase in 25-OHD levels seen in Pérez-Castrillón's study (41 ± 19 versus 47 ± 19 nmol/L, p=0.003) [1]. Although Pérez-Castrillón et al found a statistically significant relation between total cholesterol and 25-OHD (r=0.277, p=0.002), we did not find a significant relation between total cholesterol and 25-OHD in our study population.

How much vitamin D3 do the elderly need? Viljakainen HT, Palssa A, Kärkkäinen M, Jakobsen J, Lamberg-Allardt C. J Am Coll Nutr. 2006 Oct;25(5):429-35. PMID: 17031013 Conclusions: A clear dose response was noted in S-25-OHD to different doses of vitamin D3. The recommended dietary intake of 15 µg is adequate to maintain the S-25-OHD concentration around 40-55 nmol/L during winter, but if the optimal S-25-OHD is higher than that even higher vitamin D intakes are needed. Interestingly, subjects with lower vitamin D status at baseline responded more efficiently to supplementation than those with more adequate status

The second committee meeting was held August 4-5, 2009 in Washington, DC and included an Information-Gathering Workshop on August 4, 2009. The agenda for this workshop is below, along with the PowerPoint presentations that were used by the speakers during the workshop. Please note, online presentations from this meeting are subject to copyright protection. Permission from the speaker is required prior to any copying, reproducing, or rebroadcasting any portion of the speaker's presentations. Additional copyright and legal policies of The National Academies can be read in the National Academies Legal Statement.

Holick, M. F., MacLaughlin, J. A. & Doppelt, S. H. (1981) Factors that influence the cutaneous photosynthesis of previtamin D3. Science 211:590-593 When human skin was exposed to simulated solar ultraviolet radiation, epidermal 7-dehydrocholesterol was converted to previtamin D3. During prolonged exposure to simulated solar ultraviolet radiation, the synthesis of previtamin D3 reached a plateau at about 10 to 15 percent of the original 7-dehydrocholesterol content, and previtamin D3 was photoisomerized to two biologically inert isomers, lumisterol3 and tachysterol3. Increases either in skin melanin concentration or in latitude necessitated increases in the exposure time to simulated solar ultraviolet radiation required to maximize the formation, but not the total content, of previtamin D3. In order of importance, the significant determinants limiting the cutaneous production of previtamin D3 are (i) photochemical regulation, (ii) pigmentation, and (iii) latitude.

Vitamin D is associated with improved survival in early-stage non-small cell lung cancer patients. Zhou W, Suk R, Liu G, Park S, Neuberg DS, Wain JC, Lynch TJ, Giovannucci E, Christiani DC. Cancer Epidemiol Biomarkers Prev. 2005 Oct;14(10):2303-9. PMID: 16214909 In conclusion, the joint effects of surgery season and recent vitamin D intake seem to be associated with the survival of early-stage non-small cell lung cancer patients. In summary, for early-stage NSCLC patients, patients who had surgery in summer with "high" recent vitamin D intake have a statistically significantly improved RFS and OS than patients who had surgery in winter with "low" vitamin D intake. These results should be confirmed in a prospective study to assess the serum vitamin D levels at time of surgery. If the results are confirmed, our results, combined with findings in other studies, suggest that dietary vitamin D supplementation may be advisable for early stages of lung cancer patients, particularly during the winter season and in groups that tend to be deficient in vitamin D.

Vitamin D in preventive medicine: are we ignoring the evidence? Zittermann A. Br J Nutr. 2003 May;89(5):552-72. Review. PMID: 12720576 Vitamin D is metabolised by a hepatic 25-hydroxylase into 25-hydroxyvitamin D (25(OH)D) and by a renal 1alpha-hydroxylase into the vitamin D hormone calcitriol. Calcitriol receptors are present in more than thirty different tissues. Apart from the kidney, several tissues also possess the enzyme 1alpha-hydroxylase, which is able to use circulating 25(OH)D as a substrate. Serum levels of 25(OH)D are the best indicator to assess vitamin D deficiency, insufficiency, hypovitaminosis, adequacy, and toxicity. European children and young adults often have circulating 25(OH)D levels in the insufficiency range during wintertime. Elderly subjects have mean 25(OH)D levels in the insufficiency range throughout the year. In institutionalized subjects 25(OH)D levels are often in the deficiency range. There is now general agreement that a low vitamin D status is involved in the pathogenesis of osteoporosis. Moreover, vitamin D insufficiency can lead to a disturbed muscle function. Epidemiological data also indicate a low vitamin D status in tuberculosis, rheumatoid arthritis, multiple sclerosis, inflammatory bowel diseases, hypertension, and specific types of cancer. Some intervention trials have demonstrated that supplementation with vitamin D or its metabolites is able: (i) to reduce blood pressure in hypertensive patients; (ii) to improve blood glucose levels in diabetics; (iii) to improve symptoms of rheumatoid arthritis and multiple sclerosis. The oral dose necessary to achieve adequate serum 25(OH)D levels is probably much higher than the current recommendations of 5-15 microg/d.

nfluence of season and latitude on the cutaneous synthesis of vitamin D3: exposure to winter sunlight in Boston and Edmonton will not promote vitamin D3 synthesis in human skin. Webb AR, Kline L, Holick MF. J Clin Endocrinol Metab. 1988 Aug;67(2):373-8. PMID: 2839537 doi:10.1210/jcem-67-2-373 These results quantify the dramatic influence of changes in solar UVB radiation on cutaneous vitamin D3 synthesis and indicate the latitudinal increase in the length of the "vitamin D winter" during which dietary supplementation of the vitamin may be advisable.

Calcium and vitamin d supplementation decreases incidence of stress fractures in female navy recruits. Lappe J, Cullen D, Haynatzki G, Recker R, Ahlf R, Thompson K. J Bone Miner Res. 2008 May;23(5):741-9. PMID: 18433305 doi: 10.1359/jbmr.080102 Conclusions: Generalizing the findings to the population of 14,416 women who entered basic training at the Great Lakes during the 24 mo of recruitment, calcium and vitamin D supplementation for the entire cohort would have prevented 187 persons from fracturing. Such a decrease in SFx would be associated with a significant decrease in morbidity and financial costs.

Teenage girls and elderly women living in northern Europe have low winter vitamin D status. Andersen R, Mølgaard C, Skovgaard LT, Brot C, Cashman KD, Chabros E, Charzewska J, Flynn A, Jakobsen J, Kärkkäinen M, Kiely M, Lamberg-Allardt C, Moreiras O, Natri AM, O'brien M, Rogalska-Niedzwiedz M, Ovesen L. Eur J Clin Nutr. 2005 Apr;59(4):533-41. PMID: 15714215 doi:10.1038/sj.ejcn.1602108 CONCLUSION: Vitamin D status is low in northern Europe during winter. More than one-third of the adolescent girls have vitamin D status below 25 nmol/l and almost all are below 50 nmol/l. Two-thirds of the elderly community-dwelling women have vitamin D status below 50 nmol/l. Use of vitamin D supplements is a significant positive determinant for S-25OHD for both girls and women (P = 0.001). SPONSORSHIP: The European Fifth Framework Programme (Contract No. QLK1-CT-2000-00623)

Food chain as origin of vitamin D in fish D. Sunita Rao and N. Raghuramulu. Comparative Biochemistry and Physiology Part A: Physiology Volume 114, Issue 1, May 1996, Pages 15-19 doi:10.1016/0300-9629(95)02024-1 Plankton, the chief food source of fish, was assessed as the possible dietary origin of vitamin D in fish. The presence of vitamin D compounds were examined in fresh water phytoplankton and zooplankton employing a series of chromatographic procedures. Abundant amounts of provitamins D and vitamins D (D2 and D3) were found in the fresh water plankton. The high amount of vitamin D observed may be due to exposure of plankton to sunlight because the plankton were caught during the summer month. Thus, plankton may be an important contributor to vitamin D in fish.

Incidence of reported cold/influenza symptoms according to season. The 104 subjects in the placebo group (light shade) reported cold and flu symptoms year around with the most symptoms in the winter. While on 800 IU per day (intermediate shade) the 104 test subjects were as likely to get sick in the summer as the winter. Only one of the 104 test subjects had cold/influenza symptoms during the final year of the trial, when they took 2,000 IU of vitamin D per day (dark shading). Adapted from: Aloia JF, Li-Ng M: Epidemic influenza and vitamin D. Epidemiol Infect 2007; 135: 1095-1096

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.

Maintaining adequate levels of vitamin D during winter months requires a daily dose of 20 micrograms, four times the current recommended dose, says a new study. The study, led by Susan Sullivan from the University of Maine, has important implications for ongoing consultations on vitamin D recommendations, with the current level of five micrograms (200 International Units) seen by many as insufficient.

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

"Last Wednesday night I gave a lecture to my clients on hunter-gatherer diets. The turnout was great and the information was well-received. I had it professionally video-recorded and will probably offer this as a DVD for sale (with the handout included). Watch for it in the future. Part of what I discussed was vitamin D3 supplementation. Since I have been supplementing with 4,000-10,000 Units of D3 per day I have noted enhanced recovery and size response from my training. Apparently, skeletal muscle has both surface receptors and nuclear receptors for D3 that augment calcium flux during contraction (from surface receptors) and have steroid-like effects at the nuclear level WRT protein synthesis. This D3 supplementation is not really "supplementation" but is instead "augmentation" to levels that would be normal if we got normal sun exposure as we did in our evolutionary past. Check out www.vitamindcouncil.org for more information. Also, check out this abstract below for your consideration. Also, check out this article."