Researchers from the San Diego School of Medicine at the University of California have found a correlation between vitamin D and incidence of Type 1 diabetes. The 6 year study of the blood levels of nearly 2,000 individuals suggested a preventive role for vitamin D. The research appears the December issue of Diabetologia, a publication of the European Association for the Study of Diabetes.
"Previous studies proposed the existence of an association between vitamin D deficiency and risk of and Type 1 diabetes, but this is the first time that the theory has been tested in a way that provides the dose-response relationship," said Cedric Garland, DrPH, FACE, professor in UCSD's Department of Family and Preventive Medicine.
This study used samples from millions of blood serum specimens. The researchers analyzed 1,000 samples of serum from healthy people who later developed type 1 diabetes and 1,000 healthy controls whose blood was drawn on or near the same date but who did not develop type 1 diabetes. By comparing the serum concentrations, investigators were able to determine the optimal serum level needed to lower an individual's risk of developing type 1 diabetes.
Based mainly on results of this study, Garland estimates that the level of 25(OH)D needed to prevent half the cases of type 1 diabetes is 50 ng/ml. A consensus of all available data indicates no known risk with this dosage.
"While there are a few conditions that influence vitamin D metabolism, for most people, 4,000 IU per day of vitamin D will be needed to achieve the effective levels," Garland suggested. He urges interested patients to ask their health care provider before increasing vitamin D intake.
"This beneficial effect is present at these intakes only for vitamin D" cautioned Garland. "Reliance should not be placed on different forms of vitamin D and mega doses should be avoided, as most of the benefits for prevention of disease are for doses less than 10,000 IU/day."