| Young African-Americans' Low Vitamin D Levels Reported
African-American teenagers tested in a recent study had a greater incidence of low vitamin D levels than participants in several earlier investigations. University and Agricultural Research Service nutrition experts reported that finding in a recent issue of the American Journal of Clinical Nutrition (volume 83, pages 1135 to 1141). Vitamin D is essential for strong bones. Good sources include vitamin D-fortified milk and juices as well as fatty fish, and sunshine--which converts a natural chemical in skin into vitamin D. At sites in 14 American cities, the scientists examined levels of 25-hydroxy vitamin D in the blood (plasma) of 359 volunteers, predominantly African-American females aged 15 to 19. This form of the vitamin is a good indicator of total vitamin D stores. The researchers found that 87 percent of the volunteers--an unexpectedly high number--had an insufficient amount of 25-hydroxy vitamin D in their plasma.
Vitamin D Deficiency Common In United States
A multi-institutional collaborative study published in the Journal of Nutrition (135:2478-2485, 2005) found vitamin D intake inadequate in certain U.S. populations. Researchers estimated intake levels of vitamin D based on age, sex and race/ethnicity. They found vitamin D intakes highest among children and teenagers and lowest among the oldest age categories. Among children ages 1 through 8, adequate intake levels for vitamin D from food were met or exceeded by 69 percent of Mexican-Americans; 59 percent of non-Hispanic whites; and 48 percent of non-Hispanic blacks. However, only 4 percent of adults over age 51 or women ages 19 through 50 were estimated to consume recommended vitamin D levels from food. Mean dietary intakes of vitamin D from food and supplements were consistently highest among non-Hispanic white populations, although only small proportions of all those over age 51 had intakes above the recommended levels.
Vitamin D and Flavonoids Examined for Impact on Breast and Ovarian ...
While risk factors for breast and ovarian cancers include menopause, obesity, family history and specific genetic mutations, researchers also are looking at the role of diet in the development, as well as the treatment and prevention of these tumors. At the 97th Annual Meeting of the American Association for Cancer Research, two groups of scientists using sophisticated statistical techniques report their findings of possible preventive properties of Vitamin D against breast cancer. Two other groups of scientists present their work analyzing the possibility that natural antioxidants found in plants, substances called flavonoids, could play a powerful role in preventing both breast and ovarian cancer. Potential Reduction in Breast Cancer Risk Associated with Vitamin D: Abstract No. 4009 Though scientists have suspected that Vitamin D helps to prevent and possibly even treat breast cancer, population-based studies on the possible link have been few and of limited scope.
Fortified Bread Boosts Vitamin D Status
HELSINKI, Finland--Fortification of bread is safe and feasible way of increasing vitamin D status, according to a recent trial investigating the bioavailability of cholecalciferol from fortified bread given to women. The results were published in the Journal of Nutrition (136:123-7, 2006). In the trial, researchers from the University of Helsinki and the Danish Veterinary and Food Administration studied cholecalciferol stability, the concentration of the added cholecalciferol, and its dispersion and bioavailability in fortified bread. Three batches of fortified low-fiber wheat and high-fiber rye breads were baked; from each batch, three samples of dough and bread were analyzed for their cholecalciferol content. Then, researchers conducted a single-blind bioavailability study, randomly assigning 41 healthy women--25 to 45 years old with mean serum 25-hydroxyvitamin D concentration 29 nmol/L (range 1245 nmol/L)-- to one of four study groups.
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