Celebrity watchdogs are buzzing that the hideous red marks that erupted around Holmes' mouth shortly after the couple announced their romance in early May are the nasty side effects of a Church of Scientology "detoxification" procedure involving the vitamin niacin...
The B-complex vitamin - which is used in traditional medicine to decrease cholesterol and improve circulation - can cause a red flush on the face and a diffuse itchy rash on the body when taken in large doses.
So was niacin the cause of Katie's temporary disfigurement?
At Lowdown's request, Manhattan dermatologist Paul Frank examined photographs of the future Mrs. Cruise.
"Although I can't say for sure, this looks like a cold-sore attack," Frank said. "Niacin shouldn't trigger cold sores."
Well then, what does?
"Stress is the No. 1 cause," he replied. "God knows Scientology stresses me out!"
Scientologists say no to this...
"Whatever is on Katie's face has nothing to do with us. It's insulting that you would ask such a thing."