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Vitamin D supplementation and total mortality: a meta-analysis of randomized controlled trials. Autier P, Gandini S. Arch Intern Med. 2007 Sep 10;167(16):1730-7. Review. PMID: 17846391 Conclusions Intake of ordinary doses of vitamin D supplements seems to be associated with decreases in total mortality rates. The relationship between baseline vitamin D status, dose of vitamin D supplements, and total mortality rates remains to be investigated. Population-based, placebo-controlled randomized trials with total mortality as the main end point should be organized for confirming these findings.

Venn BJ, Green TJ, Moser R, Mann JI. Related Articles, Links Free Full Text Comparison of the effect of low-dose supplementation with L-5-methyltetrahydrofolate or folic acid on plasma homocysteine: a randomized placebo-controlled study. Am J Clin Nut

In healthy people who have been exposed to tuberculosis, a single oral dose of vitamin D enhances their immunity against this bacterial infection.

Martineau AR, Wilkinson RJ, Wilkinson KA, Newton SM, Kampmann B, Hall BM, Packe GE, Davidson RN, Eldridge SM, Maunsell ZJ, Rainbow SJ, Berry JL, Griffiths CJ. A single dose of vitamin D enhances immunity to mycobacteria. Am J Respir Crit Care Med. 2007

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]

The same annual dose of 292 000 IU of vitamin D(3) (cholecalciferol) on either daily or four monthly basis for elderly women: 1-year comparative study of the effects on serum 25(OH)D(3) concentrations and renal function. Pekkarinen T, Välimäki VV, Aarum S, Turpeinen U, Hämäläinen E, Löyttyniemi E, Välimäki MJ. Clin Endocrinol (Oxf). 2009 May 25. [Epub ahead of print] PMID: 19486025 DOI: 10.1111/j.1365-2265.2009.03637.x

A positive dose-response effect of vitamin D supplementation on site-specific bone mineral augmentation in adolescent girls: a double-blinded randomized placebo-controlled 1-year intervention. Viljakainen HT, Natri AM, Kärkkäinen M, Huttunen MM, Palssa A, Jakobsen J, Cashman KD, Mølgaard C, Lamberg-Allardt C. J Bone Miner Res. 2006 Jun;21(6):836-44. PMID: 16753014 doi: 10.1359/jbmr.060302 We conclude that the current vitamin D recommendation for adolescent girls, at least in the northern latitudes, is too low to ensure sufficient vitamin D status during winter. Intake of vitamin D at rates of 10-15 μg/day aids to maintain stable S-25(OH)D concentrations during winter. Vitamin D induced BMC augmentation by decreasing bone resorption, but not affecting bone formation, which was reflected by the biochemical markers of bone turnover. Optimizing bone mineral gain in adolescence is crucial to the prevention of osteoporosis later in life. Increasing vitamin D intake to 10-15 μg/day aids in attaining this goal.

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.

Summary of evidence-based review on vitamin D efficacy and safety in relation to bone health. Cranney A, Weiler HA, O'Donnell S, Puil L. Am J Clin Nutr. 2008 Aug;88(2):513S-519S. Review. PMID: 18689393 We found inconsistent evidence of an association between serum 25-hydroxyvitamin D [25(OH)D] concentration and bone mineral content in infants and fair evidence of an association with bone mineral content or density in older children and older adults. The evidence of an association between serum 25(OH)D concentration and some clinical outcomes (fractures, performance measures) in postmenopausal women and older men was inconsistent, and the evidence of an association with falls was fair. We found good evidence of a positive effect of consuming vitamin D-fortified foods on 25(OH)D concentrations. The evidence for a benefit of vitamin D on falls and fractures varied. We found fair evidence that adults tolerated vitamin D at doses above current dietary reference intake levels, but we had no data on the association between long-term harms and higher doses of vitamin D.

Vitamin D requirements during lactation: high-dose maternal supplementation as therapy to prevent hypovitaminosis D for both the mother and the nursing infant. Hollis BW, Wagner CL. Am J Clin Nutr. 2004 Dec;80(6 Suppl):1752S-8S. PMID: 15585800

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

Low-dose supplementation with active hexose correlated compound improves the immune response to acute influenza infection in C57BL/6 mice. Nogusa S, Gerbino J, Ritz BW. Nutr Res. 2009 Feb;29(2):139-43. PMID: 19285605 doi:10.1016/j.nutres.2009.01.005

Effects of pistachios on cardiovascular disease risk factors and potential mechanisms of action: a dose-response study. Gebauer SK, West SG, Kay CD, Alaupovic P, Bagshaw D, Kris-Etherton PM. Am J Clin Nutr. 2008 Sep;88(3):651-9. PMID: 18779280

"Possible effects of berberine, a chemical found in small amounts in goldenseal, include headache, slow heart rate, nausea, vomiting, abdominal bloating, and low white blood cell count. It is not clear if the amount of berberine in goldenseal products is enough to cause these reactions. Toxic doses of berberine may cause seizures or irritation of the esophagus and stomach when taken by mouth. Berberine used intravenously (through the veins) may cause abnormal heart rhythms. Based on laboratory and animal studies, berberine may increase blood concentrations of bilirubin. Berberine theoretically may cause low blood pressure, although a different chemical in goldenseal, hydrastine, may actually cause increased blood pressure. There is limited study of the blood pressure effects of these agents in humans. Based on laboratory and animal studies, the use of goldenseal or berberine could increase the risk of bleeding. However, there are no reliable published reports of bleeding in humans. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary. Based on an initial report, goldenseal or berberine may cause increased sun sensitivity, although this is not a commonly reported symptom. Based on laboratory studies, berberine may lower blood sugar. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare provider, and medication adjustments may be necessary. "

"NOTTINGHAM, England, Dec. 29 (UPI) -- A drug derived from a mushroom -- cordycepin -- may be used to treat some cancers, British researchers say. Dr. Cornelia de Moor of The University of Nottingham in England and colleagues are investigating the drug originally extracted from a rare parasitic mushroom called cordyceps that grows on caterpillars. The researchers say low-dose cordycepin seems to inhibit the uncontrolled growth and division of cells and at high doses it also inhibits growth by stopping cells from sticking together. Both of these effects, they say, probably have the same underlying mechanism -- interfering with the production of cell proteins.

Berberine reduces the hypoxic-ischemic insult in rat pup brain. Benaissa F, Mohseni-Rad H, Rahimi-Moghaddam P, Mahmoudian M. Acta Physiol Hung. 2009 Jun;96(2):213-20. PMID: 19457765 DOI: 10.1556/APhysiol.96.2009.2.6 Pathologic review of the samples obtained from rats treated with different doses of berberine in comparison with samples from pups treated by normal saline showed that there was a significant reduction of brain injury and edema in the rats treated with berberine. Our study also demonstrates that berberine reduces brain ischemic-hypoxic injury dose-dependently. Therefore, beberine may be considered as useful anti-stroke agent.

n-3 fatty acids and cardiovascular disease. Breslow JL. Am J Clin Nutr. 2006 Jun;83(6 Suppl):1477S-1482S. Review. PMID: 16841857 The results of prospective cohort studies indicate that consuming fish or fish oil containing the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is associated with decreased cardiovascular death, whereas consumption of the vegetable oil-derived n-3 fatty acid {alpha}-linolenic acid is not as effective. Randomized control trials (RCTs) in the context of secondary prevention also indicate that the consumption of EPA plus DHA is protective at doses 3 g/d, EPA plus DHA can improve cardiovascular disease risk factors, including decreasing plasma triacylglycerols, blood pressure, platelet aggregation, and inflammation, while improving vascular reactivity. Mainly on the basis of the results of RCTs, the American Heart Association recommends that everyone eat oily fish twice per week and that those with coronary heart disease eat 1 g/d of EPA plus DHA from oily fish or supplements. Directions for future research include 1) RCTs to confirm the initial trials showing that EPA plus DHA decreases cardiovascular death and additional studies to determine whether this effect is due to EPA, DHA, or the combination; the dosage of the effective components; and whether the mechanism of action in humans is prevention of fatal arrhythmias. 2) Clinical studies to determine whether the reduction in cardiovascular disease risk factors is due to EPA, DHA, or the combination and the dosage of the effective components. 3) Clinical studies to determine whether vegetable oil-derived {alpha}-linolenic acid added to a diet enriched in n-6 fatty acids can effectively substitute for fish oil-derived EPA plus DHA.

Serum vitamin D concentration and prostate cancer risk: a nested case-control study. Ahn J, Peters U, Albanes D, Purdue MP, Abnet CC, Chatterjee N, Horst RL, Hollis BW, Huang WY, Shikany JM, Hayes RB; Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Project Team. J Natl Cancer Inst. 2008 Jun 4;100(11):796-804. Epub 2008 May 27. PMID: 18505967 doi:10.1093/jnci/djn152 CONCLUSION: The findings of this large prospective study do not support the hypothesis that vitamin D is associated with decreased risk of prostate cancer; indeed, higher circulating 25(OH)D concentrations may be associated with increased risk of aggressive disease. In summary, results from this large prospective study of men who underwent standardized prostate cancer screening in the context of a screening trial do not support the hypothesis that higher serum vitamin D status is associated with decreased risk of prostate cancer. The study showed no association of vitamin D level with nonaggressive disease; however, it raises the possibility that higher vitamin D level may be associated with increased risks for aggressive disease, although a clear monotonic dose-response relationship was lacking. Along with recent reports of adverse associations for higher vitamin D status and risk of pancreatic (32) and esophageal (33,34) cancer, caution should be taken in recommending high doses of vitamin D or sunlight exposure to the general public for prostate cancer prevention. Future analyses are warranted to confirm these results and to further clarify the effects of vitamin D on aggressive prostate cancer.

Should new vitamin D recommendations be made? According to a new study carried out at the University of California at Davis, the recommended dose of vitamin D that most experts recommend taking is too low during the winter months when there's less direct sunlight

Fall prevention with supplemental and active forms of vitamin D: a meta-analysis of randomised controlled trials. Bischoff-Ferrari HA, Dawson-Hughes B, Staehelin HB, Orav JE, Stuck AE, Theiler R, Wong JB, Egli A, Kiel DP, Henschkowski J. BMJ. 2009 Oct 1;339:b3692. doi: 10.1136/bmj.b3692. PMID: 19797342 doi: 10.1136/bmj.b3692 Conclusions Supplemental vitamin D in a dose of 700-1000 IU a day reduced the risk of falling among older individuals by 19% and to a similar degree as active forms of vitamin D. Doses of supplemental vitamin D of less than 700 IU or serum 25-hydroxyvitamin D concentrations of less than 60 nmol/l may not reduce the risk of falling among older individuals.