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Epidemiological studies analyze the distribution and determinants of health and disease conditions. An epidemiological study conducted by researchers at University of California San Diego School of Medicine and Seoul National University suggests that deficiency in vitamin D may increase the risk of developing diabetes. Researchers studied 903 healthy adults 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, fasting plasma glucose and oral glucose tolerance were measured.
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 over the course of time.
For the study, the researchers identified the minimum healthy level of 25-hydroxyvitamin D in blood plasma to be 30 nanograms per milliliter. This is 10 ng/ml above the level recommended in 2010 by the Institute of Medicine, now part of The National Academies, a health advisory group to the federal government. Many groups, however, have argued for higher blood serum levels of vitamin D, as much as 50 ng/ml.
Participants with blood levels of 25-hydroxyvitamin D that were above 30 ng/ml had one-third of the risk of diabetes and those with levels above 50 ng/ml had one-fifth of the risk of developing diabetes, those with 25-hydroxyvitamin D levels below 30 ng/ml were considered vitamin D deficient. To reach 25-hydroxyvitamin D levels of 30 ng/ml, Garland said would require dietary supplements of 3,000 to 5,000 international units (IU) per day, less with the addition of moderate daily sun exposure with minimal clothing.
haleplushearty.org