Having sufficient vitamin D levels during young adulthood may reduce the risk of adult-onset type 1 diabetes by up to 50%.
The study, conducted by researchers at Harvard School of Public Health, provides the strongest evidence to date that supports vitamin D’s protective role against type 1 diabetes.
In type 1 diabetes a person’s immune system attacks and disables the insulinproducing cells in the pancreas, and as a result, the person can no longer produce insulin. Insulin is a hormone needed to convert sugars and starches into energy.
The Harvard researchers examined blood samples of US military personnel. They identified 310 individuals diagnosed with type 1 diabetes between 1997 and 2009. They examined the blood samples taken before the onset of the disease, and compared them with 613 matched healthy control samples.
The researchers found that white, non-hispanic, healthy young adults with higher vitamin D levels (≥40 ng/ml) had about half the risk of developing type 1 diabetes than those with the lowest levels (<30 ng/ml). The researchers found no association between vitamin D status and diabetes among Hispanic and non-Hispanic black participants, although this may be due to the small number of individuals in these groups.
Alberto Ascherio, MD, PhD, the study’s senior author concludes,
“The risk of type 1 diabetes appears to be increased even at vitamin D levels that are commonly regarded as normal, suggesting that a substantial proportion of the population could benefit from increased vitamin D intake.”