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Tufts MC physician receives $40 million NIH grant to study the effects of vitamin D on type 2 diabetes

Endocrinologist and Co-Director of the Diabetes Center at Tufts Medical Center Anastassios G. Pittas, MD, MS may be on the verge of an important scientific breakthrough in the fight against type 2 diabetes. And the solution is much simpler than you might think.

A research team led by Pittas recently received a National Institutes of Health grant of more than $40 million over five years to conduct the Vitamin D and Type 2 diabetes (D2d) study (, a nationwide clinical trial to test whether vitamin D supplementation can reduce the likelihood of developing diabetes in people at the highest risk for the disease.

Essential research to reduce diabetes in the U.S.

A chronic disease with no known cure, diabetes can lead to potentially life-threatening complications, including stroke, blindness, and diseases of the heart, kidney and nervous system. According to the Centers for Disease Control and Prevention, diabetes resulted in more than 69,000 fatalities in the United States in 2010 and is now the 7th-leading cause of death in the country today. About two million new people over age 20 were diagnosed with diabetes in 2010 alone. Currently, nearly 26 million Americans are living with diabetes while 79 million more (about one-third of the adult U.S. population) are at a high risk for developing the disease. The American Diabetes Association estimates that diabetes costs the U.S. health care system approximately $245 billion in 2012.

“It is critically important to find new methods that are safe, effective and easy to use to stem the tide of future diabetes cases,” said Pittas. “Even though it is well-established that maintaining a healthy diet and staying physically active can lower the risk of diabetes, the number of people with the disease continues to increase.”

Is vitamin D the solution?

Commonly synthesized through sunlight exposure and found in many foods such as dairy products and seafood, vitamin D also can be easily obtained at any pharmacy or supermarket. Sales of vitamin D supplements in the United States have skyrocketed to $425 million annually, making it one of the top selling supplements in the country and one of the most talked about topics in health and medicine.  “While there is a lot of hype about vitamin D and its health benefits, there is not yet any conclusive evidence from long-term clinical trials to support a recommendation of vitamin D supplementation for diabetes prevention,” cautioned Pittas.

The D2d study, which is coordinated out of the Division of Endocrinology at Tufts Medical Center, is the first of its kind to specifically examine whether vitamin D has an effect on prevention of type 2 diabetes. If the study confirms Pittas’ hypothesis, it could have a significant impact on the quality of life for millions of people and could potentially save the American health care system billions of dollars.

About 2,500 people at high risk for diabetes will participate in the D2d study, which will take place at 20 medical centers in 17 different states across the country. Participants will receive either vitamin D supplementation or placebo and will be followed for development of diabetes twice a year for up to four years.  Results are expected in 2018.

“At the completion of the study, our goal is to have conclusive evidence as to whether vitamin D supplementation lowers the risk of diabetes,” said D2d Project Manager Patricia Sheehan, RN, MPH, MS. “The first step in reaching this objective is encouraging people at high risk for diabetes to take part in this important clinical trial.”

For more information or to sign up to participate in the study, please call 617-636-2843, e-mail or visit the study’s website at For media, please read the press release.

D2d study collaborating clinical sites


Tufts Medical Center (Boston, MA)


National Institute of Diabetes and Digestive and Kidney Diseases – Phoenix (Phoenix, AZ)


Los Angeles Roybal Comprehensive Health Center (Los Angeles, CA)

Stanford University Medical Center (Palo Alto, CA)


Translational Research Institute for Metabolism and Diabetes (Orlando, FL)


Atlanta VA Clinical Research Center (Decatur, GA)


Northwestern University (Chicago, IL)


University of Kansas Medical Center (Kansas City, KS)


Pennington Biomedical Research Center (Baton Rouge, LA)

Tulane University Health Sciences (New Orleans, LA)


Maine Medical Center - CORE (Portland, ME)


MedStar Health Research Institute (Hyattsville, MD)


HealthPartners Riverside Clinic (Minneapolis, MN)


Omaha VA Medical Center (Omaha, NE)

New York

Beth Israel Medical Center (New York, NY)

North Carolina

Duke Health Center (Durham, NC)

South Carolina

MUSC Weight Management Center (Charleston, SC)


University of Tennessee Health Science Center (Memphis, TN)


Baylor College of Medicine (Houston, TX)

University of Texas Southwestern Medical Center (Dallas, TX)