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An evaluation of the vitamin D3 content in fish: Is the vitamin D content adequate to satisfy the dietary requirement for vitamin D? Lu Z, Chen TC, Zhang A, Persons KS, Kohn N, Berkowitz R, Martinello S, Holick MF. J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):642-4. Epub 2007 Jan 30. PMID: 17267210 doi: 10.1016/j.jsbmb.2006.12.010 Surprisingly, farmed salmon had approximately 25% of the vitamin D content as wild salmon had. The vitamin D content in fish varied widely even within species. These data suggest that the tables that list the vitamin D content are out-of-date and need to be re-evaluated. Little is known about the effect of cooking on the vitamin D content in fish. When farm salmon was baked, almost all of the vitamin D content, i.e. 240 IU of vitamin D3 was recovered from 3.5 oz. of salmon. The initial concentration in the uncooked salmon was 245 IU of vitamin D3. However, when the salmon was fried in vegetable oil, approximately 50% (123 IU of vitamin D3 was recovered.) We also evaluated the vitamin D content in mackerel which is traditionally considered to be an excellent source of vitamin D3 because of its oily content. However, in the one sample that we tested, we only observed 24 IU of vitamin D3 in 3.5 oz.

Optimal vitamin D status attenuates the age-associated increase in systolic blood pressure in white Americans: results from the third National Health and Nutrition Examination Survey. Judd SE, Nanes MS, Ziegler TR, Wilson PW, Tangpricha V. Am J Clin Nutr. 2008 Jan;87(1):136-41. PMID: 18175747 Conclusions: SBP is inversely associated with serum vitamin D concentrations in nonhypertensive white persons in the United States. This observation provides a rationale for studies on the potential effects of vitamin D supplementation as a method to reduce SBP in persons at risk of hypertension.

Childhood sun exposure influences risk of multiple sclerosis in monozygotic twins. Islam T, Gauderman WJ, Cozen W, Mack TM. Neurology. 2007 Jul 24;69(4):381-8. PMID: 17646631 Conclusion: Early sun avoidance seems to precede the diagnosis of multiple sclerosis (MS). This protective effect is independent of genetic susceptibility to MS.

The role of vitamin D in cancer prevention. Garland CF, Garland FC, Gorham ED, Lipkin M, Newmark H, Mohr SB, Holick MF. Am J Public Health. 2006 Feb;96(2):252-61. Epub 2005 Dec 27. Review. PMID: 16380576 DOI: 10.2105/AJPH.2004.045260 Vitamin D status differs by latitude and race, with residents of the northeastern United States and individuals with more skin pigmentation being at increased risk of deficiency. A PubMed database search yielded 63 observational studies of vitamin D status in relation to cancer risk, including 30 of colon, 13 of breast, 26 of prostate, and 7 of ovarian cancer, and several that assessed the association of vitamin D receptor genotype with cancer risk. The majority of studies found a protective relationship between sufficient vitamin D status and lower risk of cancer. The evidence suggests that efforts to improve vitamin D status, for example by vitamin D supplementation, could reduce cancer incidence and mortality at low cost, with few or no adverse effects

Association between serum 25(OH)D concentrations and bone stress fractures in Finnish young men. Ruohola JP, Laaksi I, Ylikomi T, Haataja R, Mattila VM, Sahi T, Tuohimaa P, Pihlajamäki H. J Bone Miner Res. 2006 Sep;21(9):1483-8. doi: 10.1359/jbmr.060607 Conclusions: A lower level of serum 25(OH)D concentration may be a generally predisposing element for bone stress fractures. Considering the obvious need of additional vitamin D in prevention of stress fractures, the effects of vitamin D fortification of foods and supplementation will be subjects of interest for future research PMID: 16939407

Comment: The strengths of this randomized study include its high level of adherence and its use of a vitamin D dose sufficient to cause a biologically meaningful increase in serum levels. The adult daily value for vitamin D is 400 IU, but many U.S. women are vitamin-D-deficient (N Engl J Med 2007; 357:266). The Institute of Medicine considers doses up to 2000 IU to be without significant risk for adverse health effects. In addition to consuming dietary sources of vitamin D (see Table 1), most women will need supplements to achieve adequate intake. Multivitamins usually contain 400 IU of vitamin D.

Comment: Although lower risk associated with vitamin D exposure was shown most consistently for ER+/PR+ tumors, the result might simply reflect that this tumor subtype was the most common. Nonetheless, these findings support vitamin D's beneficial effects on breast cancer risk, regardless of hormone-receptor status. Sun exposure and dietary intake (Table 1) are key sources of vitamin D.

Hypovitaminosis D is associated with insulin resistance and beta cell dysfunction. Chiu KC, Chu A, Go VL, Saad MF. Am J Clin Nutr. 2004 May;79(5):820-5. PMID: 15113720 Conclusions: The data show a positive correlation of 25(OH)D concentration with insulin sensitivity and a negative effect of hypovitaminosis D on ß cell function. Subjects with hypovitaminosis D are at higher risk of insulin resistance and the metabolic syndrome. Further studies are required to explore the underlying mechanisms.

Use of cod liver oil during the first year of life is associated with lower risk of childhood-onset type 1 diabetes: a large, population-based, case-control study. Stene LC, Joner G; Norwegian Childhood Diabetes Study Group. Am J Clin Nutr. 2003 Dec;78(6):1128-34. PMID: 14668274 Conclusion: Cod liver oil may reduce the risk of type 1 diabetes, perhaps through the antiinflammatory effects of long-chain n-3 fatty acids.

The role of vitamin D in cancer prevention. Garland CF, Garland FC, Gorham ED, Lipkin M, Newmark H, Mohr SB, Holick MF. Am J Public Health. 2006 Feb;96(2):252-61. Epub 2005 Dec 27. Review. PMID: 16380576 DOI: 10.2105/AJPH.2004.045260 Vitamin D status differs by latitude and race, with residents of the northeastern United States and individuals with more skin pigmentation being at increased risk of deficiency. A PubMed database search yielded 63 observational studies of vitamin D status in relation to cancer risk, including 30 of colon, 13 of breast, 26 of prostate, and 7 of ovarian cancer, and several that assessed the association of vitamin D receptor genotype with cancer risk. The majority of studies found a protective relationship between sufficient vitamin D status and lower risk of cancer. The evidence suggests that efforts to improve vitamin D status, for example by vitamin D supplementation, could reduce cancer incidence and mortality at low cost, with few or no adverse effects.

Vitamin D and its role in skeletal muscle. Ceglia L. Curr Opin Clin Nutr Metab Care. 2009 Sep 18. [Epub ahead of print] PMID: 19770647 SUMMARY: Further studies are needed to fully characterize the underlying mechanisms of vitamin D action in human muscle tissue, to understand how these actions translate into changes in muscle cell morphology and improvements in physical performance, and to define the 25-hydroxyvitamin D level at which to achieve these beneficial effects in muscle.

Serum 25-hydroxyvitamin D and colon cancer: eight-year prospective study. Garland CF, Comstock GW, Garland FC, Helsing KJ, Shaw EK, Gorham ED. Lancet. 1989 Nov 18;2(8673):1176-8. PMID: 2572900 Blood samples taken in 1974 in Washington County, Maryland, from 25 620 volunteers were used to investigate the relation of serum 25-hydroxyvitamin D (25-OHD) with subsequent risk of getting colon cancer. 34 cases of colon cancer diagnosed between August, 1975, and January, 1983, were matched to 67 controls by age, race, sex, and month blood was taken. Risk of colon cancer was reduced by 75% in the third quintile (27-32 ng/ml) and by 80% in the fourth quintile (33-41 ng/ml) of serum 25-OHD. Risk of getting colon cancer decreased three-fold in people with a serum 25-OHD concentration of 20 ng/ml or more. The results are consistent with a protective effect of serum 25-OHD on colon cancer.

Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey. Ginde AA, Mansbach JM, Camargo CA Jr. Arch Intern Med. 2009 Feb 23;169(4):384-90. PMID: 19237723 Conclusions Serum 25(OH)D levels are inversely associated with recent URTI. This association may be stronger in those with respiratory tract diseases. Randomized controlled trials are warranted to explore the effects of vitamin D supplementation on RTI.

Strong correlations have been noted between cardiovascular diseases and low bone density / osteoporosis-connections so strong that the presence of one is considered a likely predictor of the other. This relationship has led to the hypothesis that these conditions share core pathophysiological mechanisms. Recent advances in our understanding of the complimentary roles played by vitamin D3 and vitamin K2 in vascular and bone health provide support for this hypothesis, along with insight into key metabolic dysfunctions underlying cardiovascular disease and osteoporosis. Part II, The Vitamin K Connection to Cardiovascular Health, reviews the ways in which vitamin K regulates calcium utlization, preventing vascular and soft tissue calcification while complimenting the bone-building actions of vitamin D, and also discusses vitamin K safety and dosage issues, and the necessity of providing vitamin K and vitamin A along with vitamin D to preclude adverse effects associated with hypervitaminosis D.

Association between plasma 25-hydroxyvitamin D and breast cancer risk. Crew KD, Gammon MD, Steck SE, Hershman DL, Cremers S, Dworakowski E, Shane E, Terry MB, Desai M, Teitelbaum SL, Neugut AI, Santella RM. Cancer Prev Res (Phila Pa). 2009 Jun;2(6):598-604. Epub 2009 May 26. PMID: 19470790 In summary, these results add to a growing body of evidence that adequate vitamin D stores may prevent breast cancer development. Whereas circulating 25-OHD levels of >32 ng/mL are associated with normal bone mineral metabolism, our data suggest that the optimal level for breast cancer prevention is ≥40 ng/mL. Well-designed clinical trials are urgently needed to determine whether vitamin D supplementation is effective for breast cancer chemoprevention.

To conclude, our findings suggest an association between large-dose vitamin D supplementation in infancy and an increased risk of atopy, allergic rhinitis, and asthma later in life. Further study is required to determine whether these observations could imply that vitamin D supplementation in infancy may have long-term effects on immune regulation, or if they reflect some unmeasured determinants of vitamin D supplementation Infant vitamin d supplementation and allergic conditions in adulthood: northern Finland birth cohort 1966. Hyppönen E, Sovio U, Wjst M, Patel S, Pekkanen J, Hartikainen AL, Järvelinb MR. Ann N Y Acad Sci. 2004 Dec;1037:84-95. DOI: 10.1196/annals.1337.013 PMID: 15699498

In the last post, we talked about the new report on vitamin D and cancer from the International Agency for Research into Cancer (IARC). In this one, we'll summarise what the report has to say on the balance between getting enough vitamin D through sun exposure and reducing the risk of skin cancer by being SunSmart. IARC calls for more trials to really pin down the effects of vitamin D supplements - either positive or negative - depending on how much vitamin D people already have in their system. Until then, they feel that there is no solid basis for changing any existing recommendations about vitamin D.

A recent Wall Street Journal article "Defending Against Disease -- With Vitamin D New Studies Suggest It Isn't Just Bones That Might Benefit" by the wonderful Melinda Beck highlights benefits of Vitamin D3. In TYP, we've known the benefits for years :) but it's nice to see the rest of the world catching up. The benefits of Vitamin D3 are potent, powerful immunomodulation -- to the point where autoimmune diseases, viral and bacterial infections and cancer are effectively reduced. What is the value for heart disease and diabetes prevention? In hemodialysis patients, great lessons are can be learned. Nephrologists often describe patients with severe (stage 5) chronic kidney disease (CKD) patients on hemodialysis as having 'hearts of stone, blood vessels of glass.' Unfortunately over 70% of chronic hemodialysis patients have coronary artery disease (and Lp(a)). What medical science shows is that Agatston coronary calcification scores can be dramatically reduced when vitamin D is replenished and calcium is restricted. Sevelamer (Renagel) is a calcium-free, metal-free polymer phosphate binder. In 52-weeks, calcium restriction, a phosphate-binder and vitamin D resulted in one individual in a 21% reduction in Agatston CAC score (from 968 to 756; see Figure 2).

Seasonal affective disorder (SAD) is a type of winter-time depression experienced by people those who live in northern latitudes such as those of New York, Seattle, all of Canada, and Northern Europe. I believe it is primarily a disorder of sunlight/vitamin D deficiency. Vitamin D, when administered in late winter, produces a positive effect on mood in only five days.[1] One theory for this is that vitamin D stimulates the brain to produce more serotonin. In a wintertime experiment, serum vitamin D levels doubled in six months through supplementation and dramatically increased scores on a wellbeing assessment.[2] Two groups were given either 1,000 IU or 4,000 IU of vitamin D daily. And although both groups improved, the higher dose produced better results.

Clinical Responses to a Mega-dose of Vitamin D3 in Infants and Toddlers With Vitamin D Deficiency Rickets. Soliman AT, El-Dabbagh M, Adel A, Ali MA, Aziz Bedair EM, Elalaily RK. J Trop Pediatr. 2009 Jun 8. [Epub ahead of print] PMID: 19506025 doi:10.1093/tropej/fmp040 Conclusion: An IM injection of a mega dose of cholecalciferol is a safe and effective therapy for treatment of VDD rickets in infants and toddlers with normalization of all the biochemical parameters and healing of radiological manifestations. Measurement of serum 25(OH)D level is highly recommended in all short children with a clear need for a general vitamin D supplementation for all infants and young children in Qatar.