EXETER, England—Already associated with increased risk of osteoporosis, heart disease and diabetes, a new study links deficiency of vitamin D with increased cognitive decline in older adults, English researchers report. In the study, published July 12 in the Archives of Internal Medicine (2010;170(13):1135-41), researchers explored the link between blood serum levels of 25-hydroxyvitamin D (25[OH]D, a marker of vitamin D status) and the risk of cognitive decline in a population of more than 850 older adults.
Over a six year period, subjects with serum levels of 25(OH)D <25 nmol/L—severely deficient in vitamin D—had a 60 percent increased chance of having substantial cognitive decline on several cognitive tests compared with the adults with sufficient 24(OH)D levels (≥75 nmol/L). The association was significant even after adjusting for confounders and restricting analysis to subjects who were non-demented at the start of the study.
It has been reported more than 40 percent and up to 100 percent of older adults are deficient in vitamin D, with levels directly related to sunlight exposure and physical activity. An accompanying editorial in the same issue of the journal (170(13):1099-1100) noted there is an increasing quantity of observational data linking vitamin D deficiencies to increased risk of several chronic diseases. They suggested the links suggested by the observational studies should be explored in randomized clinical trials (RCTs) to determine appropriate populations and dosages that could benefit from supplementation, as well as review the safety of such interventions.
Such research provides a great opportunity for informed retailers, said Daniel Fabricant, Ph.D., vice president, global government and scientific affairs, Natural Products Association. “I think that with all of the wonderful scientific studies coming out on vitamin D, retailers are doing themselves a disservice if they don’t have third-party literature on hand to disseminate to their customers,” he said. “This was a key part of the Dietary Supplement Health & Education Act, and unfortunately one that is under- or incorrectly used, as the idea behind allowing the dissemination of third party literature was that where the science grew the consumer would benefit and be informed in a lawful and objective manner. While retailers can’t prescribe or give medical advice, they can give out the literature in its entirety, although not right next to the product, and reference the fact that studies like this may be why groups outside of the Institute of Medicine (IOM), like the American Academy of Pediatrics, are looking to up the daily intake for vitamin D for specific populations, in this case the elderly.” For more on the regulations governing the use of third-party literature, visit the NPA Web site.