The findings, if confirmed in future studies, could lead to a role for vitamin D supplementation in preventing this serious autoimmune disease in adults. The study was published online February 3, 2013 and will appear in the March 1 print edition of the American Journal of Epidemiology.
"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.
This study provides the strongest findings to date to suggest that vitamin D may be protective against type 1 diabetes.
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 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—suggesting that inadequate vitamin D in adulthood may be an important risk factor for autoimmune diseases in general.
Long-term study of military personnel
The researchers conducted a prospective case-control study of U.S. military personnel on active duty, using blood samples from the Department of Defense Serum Repository, which contains more than 40 million samples collected from 8 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.
About vitamin D
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 "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 1,000-4,000 IU/day, which is largely considered safe, is enticing," the authors said.
This study was funded by the National Institute of Neurological Disorders and Stroke (grant NS046635).
"Preclinical Serum 25-Hydroxyvitamin D Levels and Risk of Type 1 Diabetes in a Cohort of U.S. Military Personnel," Kassandra L. Munger, Lynn I. Levin, Jennifer Massa, Ronald Horst, Tihamer Orban, and Alberto Ascherio, American Journal of Epidemiology: online February 3, 2013; March 1, 2013 print edition.
Visit the HSPH website for the latest news, press releases, and multimedia offerings.
Harvard School of Public Health is dedicated to advancing the public's health through learning, discovery, and communication. More than 400 faculty members are engaged in teaching and training the 1,000-plus student body in a broad spectrum of disciplines crucial to the health and well being of individuals and populations around the world. Programs and projects range from the molecular biology of AIDS vaccines to the epidemiology of cancer; from risk analysis to violence prevention; from maternal and children's health to quality of care measurement; from health care management to international health and human rights. For more information on the school visit: http://www.hsph.harvard.edu
HSPH on Twitter: http://twitter.com/HarvardHSPH
HSPH on Facebook: http://www.facebook.com/harvardpublichealth
HSPH on You Tube: http://www.youtube.com/user/HarvardPublicHealth
HSPH home page: http://www.hsph.harvard.edu
Marge Dwyer | EurekAlert!
Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
18.10.2017 | Materials Sciences
18.10.2017 | Physics and Astronomy
18.10.2017 | Physics and Astronomy