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Vitamin D is a nutrient that has come under increased scrutiny inrecent years as more of its roles in the human body are discovered.It has long been known to be important for healthy bone growth andmaintaining normal calcium levels in the blood. More recent studieshave also linked low vitamin-D levels to an increased risk ofdiabetes and cardiovascular disease as well as many cancers . Reduced vitamin D levels are also associated with higher fastingblood sugar, more insulin resistance and increased body fat,components of the metabolic syndrome. Vitamin D is obtained naturally through sun exposure as well asthrough certain foods, including fish, liver and eggs. It can alsobe taken through supplements, and many dairy products, margarinesand cereals are fortified with it. Although most people inCalifornia are traditionally thought to receive adequate vitamin Dthrough routine outdoor activity, this study indicates that this isnot the case in Northern California. A similar study recentlyconducted in Southern California found no difference in vitamin-Dlevels between subjects with and without metabolic syndrome, and inFlorida, even diabetics do not tend to have low vitamin-D levels.These results indicate that vitamin D levels are probably adequatefor most people living in those sunny latitudes, and that metabolicsyndrome and diabetes arise mostly because of other factors inthose areas. "That our results were so different from the study undertaken inSouthern California was amazing to us," said Jialal, who alsoserves as director of the Laboratory for Atherosclerosis andMetabolic Research at UC Davis. "The difference in latitude is notthat great, but apparently sun exposure in southern California isadequate and in northern California it is not." Controversy exists surrounding optimum blood levels of vitamin D.Current government guidelines for sufficient blood levels ofvitamin D as well as daily intake are based on those required forbone health and are much lower than what are now believed by manyexperts to help prevent cancer, diabetes and cardiovasculardisease. National Institutes of Health guidelines recommend aminimum blood level of 15 ng/mL as adequate for bone and overallhealth. However, many experts now feel that 30 to 100 ng/mL shouldbe the goal. Levels above 150 ng/mL are potentially toxic and canbe life-threatening. In this study, vitamin D levels averaged 23.1 ng/mL among peoplewith metabolic syndrome and 27.8 ng/mL in healthy controls, adifference that was found to be significant. Vitamin D deficiencyin this study was defined as less than 20 ng/mL, and was found in30 percent of subjects with metabolic syndrome and 8 percent ofhealthy controls. "Insufficiency" was defined as less than 30ng/mL: 84 percent of the metabolic syndrome group and 67 percent ofcontrols were found to have insufficient levels. Jialal's team intends to continue to investigate the connectionsbetween vitamin D and metabolic syndrome. They plan to study dietsof subjects with and without metabolic syndrome to determinewhether vitamin D intake is adequate. According to Jialal, it ispossible that people with metabolic syndrome have higher thanaverage needs for vitamin D. Because the vitamin is fat-soluble, ittends to get sequestered in fat, making it less likely to circulatein the blood and to be available to other tissues. They also plan to undertake a study on vitamin D supplementationfor people with metabolic syndrome to see if it lowers fastingblood sugars and increases insulin sensitivity, trends that wouldlower the risk of developing diabetes. "We have the potential to significantly delay or prevent theemergence of diabetes, heart attacks and strokes in people withmetabolic syndrome through vitamin D supplementation," said Dr.Jialal. "This may offer a very simple yet powerful weapon to combatthis burgeoning health problem in our society." The other UC Davis study authors include Professor Sridevi Devaraj,student volunteer Ganesh Jialal and technologist Teri Cook measuredthe vitamin-D levels. David Siegel assisted in the study design andmanuscript preparation. This study was supported by grants from theNational Institutes of Health and American Diabetes Association. Source: Carole Gan University of California - Davis Health System Additional References Citations. We are high quality suppliers, our products such as neoprene products , China diving equipment for oversee buyer. To know more, please visits ski wear .
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