This vitamin is turning out to be very important and recent data suggest that higher blood levels are associated with a reduced risk of colorectal cancer. Dr. Ralph Moss on his blog notes how the media have, not so surprisingly, made a mess of the study results. Some even imply that the vitamin is worthless. See his website at
Nutr Rev. 2006 May;64(5 Pt 1):226-33.
A potential role for vitamin D on HIV infection?
Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts, USA. email@example.com
Despite advances in the knowledge of vitamin D’s potent immunomodulatory activity, its role on HIV disease progression is unknown. Decreased concentrations of 1alpha,25-hydroxyvitamin D3, or 1,25(OH)2D, the active form of vitamin D, have been reported among HIV-infected people and attributed to defects in renal hydroxylation and increased utilization. A few studies also described low levels of 25-hydroxyvitamin D3, 25(OH)D, the vitamin obtained from solar synthesis and diet. An inverse association between 1,25(OH)2D concentrations and mortality has been reported from a small cohort of HIV-infected adults, and some cross-sectional studies have indicated positive correlations between 1,25(OH)2D and CD4+ cell counts. Additional observational studies are needed to confirm the associations between vitamin D status and HIV disease progression. These investigations would provide useful insights on the potential role of vitamin D supplementation to HIV-infected persons and the planning of intervention trials.