More evidence links low vitamin D levels to type 2 diabetes
Researchers have found more evidence that low levels of vitamin D may be a risk factor for type 2 diabetes; especially among diverse ethnic groups. The newest study doesn’t prove vitamin D levels that are low lead to diabetes, but researchers did find an association between lower levels of the hormone and metabolic syndrome that is a risk factor for the disease.
Lower levels of vitamin D associated with metabolic syndrome
The findings, presented at The Endocrine Society’s 94th Annual Meeting, showed people with low vitamin D levels are more prone to metabolic syndrome, which is a cluster of conditions that lead to chronic diseases like diabetes.
Metabolic syndrome includes several risk factors that not only increase your risk for diabetes, but also heart disease and stroke. According to the National Institutes of Health, the most important risks for metabolic syndrome are central obesity (increased waist size) and insulin resistance.
High blood pressure – greater than 130/85 and for men, waist circumference greater than 40 inches and 35 inches for women – high triglyceride levels, low HDL or good cholesterol level and fasting blood sugar greater than 100mg/dL mean metabolic syndrome is present.
The study, which focused on participants of the Diabetes Prevention Program, looked at 25-hydroxyvitamin D levels in 3 groups of subjects.
When vitamin D levels were 30.6 nanograms per milliliter, or ng/mL, the chances of diabetes were halved, compared to those in the lowest group who had a vitamin D concentration of 12.1 ng/mL.
The current recommendation for ‘healthy’ vitamin D levels from The Institute of Medicine is 25-hydroxyvitamin D level of 20 to 30 ng/mL.
"This association has been documented before, but our study expands the association to people of diverse racial and ethnic backgrounds," said the lead author, Joanna Mitri, MD, a research fellow at Tufts Medical Center in Boston. "These include minority groups that are already at higher risk of diabetes."
All of the participants were also at risk for diabetes because they had prediabetes, which affects 79 million people in the U.S., age 20 and above; per 2010 statistics from the Centers for Disease Control and Prevention.
Several components of metabolic syndrome that can lead to diabetes were also associated with low vitamin D status. In the study, people with the highest vitamin levels had smaller waist size, higher HDL cholesterol levels and lower blood sugar levels.
Mitri explains the study doesn’t prove low vitamin D leads to diabetes. "However, the metabolic syndrome is common, and progression to Type 2 diabetes is high," she said.
If more studies prove vitamin D could be a culprit for metabolic syndrome and type 2 diabetes, Mitri says it would be of “public health importance, because vitamin D supplementation is easy and inexpensive."
Past studies link diabetes, complications to low vitamin D
A 2010 study merely suggested that vitamin D could help lower risk of type 1 and type 2 diabetes, found in both animal and human studies. The finding, published in the Journal of Steroid Biochemistry and Molecular Biology, showed vitamin D supplements during pregnancy or early childhood might lower the chances of type 1 diabetes. Some observational studies also report a link between low levels of the vitamin and type 2 diabetes.
In another new finding from the Endocrine Society’s meeting, researchers unfortunately found that high doses of the sunshine vitamin failed to prevent diabetes.
Another study related to vitamin D and diabetes, conducted in 2011, showed fortifying the diet with yogurt could cut heart attack risks.
The newest finding shows there is a need for ongoing research to determine what impact low levels of vitamin D has on metabolic syndrome and type 2 diabetes,
Since the vitamin is important for overall health, it never hurts to have your vitamin D level checked. Follow your doctor’s advice about adding any supplements.
The Endocrine Society
June 25, 2012
Nature News Blog
"Vitamin D fails diabetes test"
June 9, 2012
Vitamin D and Diabetes
Updated January 25, 2014