Researchers find that vitamin D may reduce the risk of adult type 1 onset diabetes

by Barbara Hewitt on February 8, 2013

Researchers find that vitamin D may reduce the risk of adult type 1 onset diabetes

Adequate levels of vitamin D during young adulthood may reduce the risk of adult onset type 1 diabetes by as much as 50%, according to researchers. Initial studies at the Harvard School of Public Health (HSPH) in the United States provide the strongest findings to date to suggest that vitamin D may be protective against type 1 diabetes.

Scientists say that the findings, if confirmed in future studies, could lead to a role for vitamin D supplementation in preventing diabetes in adults. ‘It is surprising that a serious disease such as type 1 diabetes could perhaps be prevented by a simple and safe intervention,’ said lead author Kassandra Munger, research associate in the Department of Nutrition at HSPH.

In type 1 diabetes, once called juvenile onset or insulin dependent diabetes, the body’s immune system attacks and permanently disables the insulin making cells in the pancreas. About 5% of the estimated 25.8 million people in the United States with diabetes have type 1, according to the American Diabetes Association. Although it often starts in childhood, about 60% of type 1 diabetes cases occur after the age 20.

Previous studies have suggested that a shortage of vitamin D might boost type 1 diabetes risk, although those studies mostly examined the link between vitamin D levels in pregnancy or childhood and the risk of type 1 diabetes in children. Other research, in young adults, uncovered an association between high vitamin D levels and a lowered risk of multiple sclerosis, an autoimmune disease genetically and epidemiologically related to type 1 diabetes. This data suggests that inadequate vitamin D in adulthood may be an important risk factor for autoimmune diseases in general.

Quote from DiabetesForum.com : “A team of academic researchers has pinpointed how vitamin D3 and omega-3 fatty acids may enhance the immune system’s ability to clear the brain of amyloid plaques, one of the hallmarks of Alzheimer’s disease.”

The researchers at HSPH conducted a prospective case control study of US military personnel on active duty, using blood samples from the Department of Defense Serum Repository, which contains more than 40 million samples collected from eight million military personnel since the mid 1980s.

Identifying 310 individuals diagnosed with type 1 diabetes between 1997 and 2009, the team examined blood samples taken before onset of the disease, and compared the samples with those of 613 people in a control group. The researchers found that white, non-Hispanic, healthy young adults with higher serum levels (>75 nmol/L) of vitamin D had about half the risk of developing type 1 diabetes than those with the lowest levels of vitamin D (

‘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,’ said Alberto Ascherio, professor of epidemiology and nutrition at HSPH, the study’s senior author.

Worldwide, an estimated 1 billion people have inadequate levels of vitamin D in their blood, and deficiencies can be found in all ethnicities and age groups. While sun exposure is an excellent source of vitamin D, sunscreen, clothing, skin pigmentation, and winter months reduce vitamin D production. Food tends to be a poor source of vitamin D, with so called good sources, such as salmon and fortified milk, containing 400IU or less per serving.

‘Whereas it is premature to recommend universal use of vitamin D supplements for prevention of type 1 diabetes, the possibility that many cases could be prevented by supplementation with 1,000 to 4,000 IU/day, which is largely considered safe, is enticing,’ the authors said.


The opinions expressed in this article do not necessarily reflect the views of the DiabetesForum.com Community and should not be interpreted as medical advice. Please see your doctor before making any changes to your diabetes management plan.

{ 0 comments… add one now }

Leave a Comment

Previous post:

Next post: