An epidemiological study conducted by researchers at University of California San Diego School of Medicine and Seoul National University suggests that persons deficient in vitamin D may be at much greater risk of developing diabetes.
The scientists studied a cohort of 903 healthy adults (mean age: 74) with no indications of either pre-diabetes or diabetes during clinic visits from 1997 to 1999, and then followed the participants through 2009. Vitamin D levels in blood were measured during these visits, along with fasting plasma glucose and oral glucose tolerance.
Over the course of time, there were 47 new cases of diabetes and 337 new cases of pre-diabetes, in which blood sugar levels are higher than normal but not yet high enough to be categorized as type 2 diabetes.
Study co-author Cedric F. Garland, DrPH, adjunct professor in the UC San Diego School of Medicine Department of Family Medicine and Public Health, said persons with 25-hydroxyvitamin D levels below 30 ng/ml were considered vitamin D deficient. These persons, the researchers found, were up to five times at greater risk for developing diabetes than people with levels above 50 ng/ml.
Garland, who has previously investigated connections between vitamin D levels and various types of cancer, said the study builds upon previous epidemiological research linking vitamin D deficiency to a higher risk of diabetes. Epidemiological studies analyze the distribution and determinants of health and disease conditions. They do not necessarily prove cause-and-effect.
"Further research is needed on whether high 25-hydroxyvitamin D levels might prevent type 2 diabetes or the transition from pre-diabetes to diabetes," said Garland. "But this paper and past research indicate there is a strong association."
The current recommended average daily amount of vitamin D is 400 IU for children up to 1 year; 600 IU for ages 1 to 70 years (less for pregnant or breastfeeding women) and 800 IU for persons over 70, according to the National Institutes of Health. Higher daily amounts of vitamin D are generally considered safe, but blood serum levels exceeding 125 ng/ml have been linked to adverse side effects, such as nausea, constipation, weight loss, heart rhythm problems and kidney damage.
Courtesy: NewsMedicalLifeSciences
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