The November 10 issue of Newsweek contains a cover article entitled "God And Health - Is Religion Good Medicine? Why Science Is Starting To Believe"
The article mentions, on page 50:
"Dr. Suki Tepperberg, a family physician in Dorchester, Mass., has concerns about people who put too much faith in God's will. One of her patients, a Jehovah's Witness who has diabetes and hypertension, believes her illness is in God's hands and sometimes eats destructively, harming her health. Tepperberg is worried that, while this woman could take better care of herself, "she believes God really is the ultimate decision-maker".
I'll try linking to the article here:
http://http://www.msnbc.com/news/987695.asp?cp1=1
Sometimes the hyperlinky-dinky doesn't seem to work right.