Thank you to Sayer Ji at GreenMedInfo.com (www.greenmedinfo.com) for posting this resource on FaceBook for comprehensive Vitamin D studies.
This is the link to the home page of Henry Lahore's Vitamin D Wiki:
http://www.vitamindwiki.com/tiki-index.php
Under the topic Celiac for example you get a synopsis and then a list of studies:
Celiac and vitamin D
http://www.vitamindwiki.com/tiki-index.php?page_id=745
Summary of the following material August 2010
Celiac disease has a strong genetic component.
Most, but not all, people with celiac disease have a gene variant.
An adequate level vitamin D seems to decrease the probability of getting celiac disease.
Celiac disease causes poor absorption of nutrients such as vitamin D.
Bringing the blood level of vitamin D back to normal in patients with celiac disease decreases symptoms.
There are hints that vitamin D may cure the disease. - see video, etc.
The prevalence of celiac disease, not just its diagnosis has increased 4X to 10X in the past 50 years