Tufts University researchers isolated a factor in diabetes research that may reduce the risk of diabetes developing from a pre-diabetic condition. They spent several years studying and analyzing studies of the possible link between Vitamin D and reduced risk of diabetes for several years.
Recently, the researchers published their newest findings, which showed that high-risk patients with the highest blood levels of the vitamin were at 28% lower risk of developing diabetes than were those with the lowest levels.
Led by Anastassios Pittas, MD, an associate professor at Tufts School of Medicine and an adjunct associate professor at the Friedman School, the team studied 2.039 participants in the Diabetes Prevention Program (DPP), a multicenter trial of approaches to prevent diabetes in pre-diabetic people.
Unlike previous studies that measured Vitamin D status only once, blood levels of the vitamin D in the group were tested many times over an average of 2.7 years. After adjusting for all other risk factors and for DPP life adjustments in half of the patients, researchers found the top one-third with the highest levels of Vitamin D were at significantly less risk of developing diabetes.
“The findings are very promising but do not prove cause and effect,” Dr Pittas warns, “and the evidence to support general supplementation with vitamin D for diabetes prevention does not currently exist.
“There have been numerous previous occasions where highly encouraging data from observational studies led to irrational exuberance and widespread adoption of the intervention which proved premature, as subsequent trials did not confirm the benefit (e.g. hormone therapy, Vitamin E).”
However, in a 2011 random trial published in the American Journal of Clinical Nutrition, Pittas and his colleagues found that Vitamin D improved the workings of the pancreas, an organ that plays a key role in the disease. The researchers compared Vitamin D levels in 608 women recently diagnosed with diabetes to levels in 559 women without diabetes.
After adjusting for other pertinent factors, the study showed that those with the highest blood levels of Vitamin D were 48% less likely to have developed diabetes than those women with the lowest levels.
Also in 2011, the research team studied a systematic review published in the European Journal of Clinical Nutrition. They analyzed 11 prior randomized trials and 8 observational studies of Vitamin D and diabetes. Their conclusion was that daily intake of Vitamin D in excess of 500 IU was associated with a 13% lower risk of diabetes than daily intake of less than 200 IU. Those with the highest blood levels of Vitamin D had a 43% lower risk of developing diabetes compared to those with the lowest levels.
Dr Pittas said, “These promising findings from observational studies about Vitamin D and diabetes need to be confirmed in clinical trials. If the association between Vitamin D and diabetes is confirmed, there are important implications because Vitamin D is easy and inexpensive to supplement.”
He observed that it’s best to follow the daily recommendations of the Institute of Medicine, which call for 600 IU of Vitamin D for those under 70 years of age and for 800 IU for those over 70 years of age.
from Tufts University Health & Nutrition Letter, June 2012 Current study published in Diabetes Care