Friday, June 08, 2007

Coffee, Tea or me?

For those who wanted to know, this was the topic of my presentation at the meeting, a case series of 4 patients with osteosclerosis from fluoride toxicity associated with tea consumption. The presentation was well-received, and I had numerous questions from the audience since this is extremely rare in the USA. However, fluorosis appears to be endemic in some parts of the world, probably related to high tea consumption and fluoride levels in drinking water. This generated an interesting discussion at the meeting because some amongst the audience came from these endemic areas and had some experience as well. We published this in a journal this month. I've included the abstract:
Acquired osteosclerosis is a rare disorder of bone formation but an important consideration in adults with sclerotic bones or elevated bone density results. In such patients, malignancy, hepatitis C, and fluorosis should all be considered when making a diagnosis. We describe 4 patients evaluated at our Metabolic Bone Disease Clinic from May 1, 1997, to July 1, 2006, whose bone disorders resulted from chronic fluoride exposure due to excessive tea intake.
Three of these patients had toxic serum fluoride levels (>15 μmol/L). Although the clinical presentation of the patients varied, all 4 had an unexpectedly elevated spine bone mineral density that was proportionately higher than the bone mineral density at the hip. Other clinical features included gastrointestinal symptoms such as nausea, vomiting, and weight loss; lower extremity pain sometimes associated with stress fractures of the lower extremities; renal insufficiency; and elevated alkaline phosphatase levels. Readily available, tea often contains high levels of fluoride. Obsessive-compulsive drinking behaviors and renal insufficiency may predispose to excessive fluoride consumption and accumulation. The current cases show that fluoride-related bone disease is an important clinical consideration in patients with dense bones or gastrointestinal symptoms and a history of excessive tea consumption. Furthermore, fluoride excess should be considered in all patients with a history of excessive tea consumption, especially due to its insidious nature and nonspecific clinical presentation.
Some interesting numbers:
Recommended adult intake: 3-4 mg fluoride/day
Fluoride content of regular tea: 2-6.5 mg per liter
Fluoride content in jasmine tea: >200 mg per liter
So, something to think about the next time you order that 3rd glass of teh tarik.