This new study involved more than 2000 people who were pre-diabetic or had risk factors (family history) for diabetes. These people were followed for more than 3 years and will continue to be followed for several more years.
The study did not include people who already had diabetes. It would be interesting to see the study expanded to include those who already have the condition or who have metabolic syndrome.
I believe in it! I personally take 6000 IU per day with my Doctor's blessing. I must admit though that I backed off on taking it lately as I have been experimenting with some of my other supplements. I have found that my blood sugar numbers have gone up a bit so I've learned my lesson. I will keep taking the 6000 IU for now on without fail! To read the study follow this link http://diabetes.webmd.com/news/20110628/study-vitamin-d-may-cut-risk-of-diabetes?src=RSS_PUBLIC