Fluoride in tea not necessarily beneficial for teeth

BARCELONA, Spain/LEIPZIG, Germany: Britons may need to rethink their national habit of afternoon tea, as new research presented at the IADR meeting in Barcelona in Spain suggests that the world’s most-consumed beverage contains more fluoride than previously thought. According to a study led by Dr Gary Whitford from the Medical College of Georgia, the concentration of fluoride in black tea can be as high as 9 mg/l compared to 1–5 mg/l found in earlier studies. The findings could explain the occurrence of advanced skeletal and dental fluorosis, a health condition that affects the stability of teeth and bones.

Whitford found that tea leaves accumulate not only fluoride (600 to more than 1,000 mg/kg), but also large amounts of aluminium. When the leaves are brewed, both substances form insoluble aluminium fluoride, which cannot be detected by common fluoride detection methods. By breaking the aluminium-fluoride bond through diffusion, he found that the amount of fluoride in all cases was 1.4 to 3.3 times higher. Dr Whitford said that this additional fluoride does not contribute to fluorosis when consumed moderately but heavy drinkers should be aware of the danger.

Fluorosis affects more than ten million people worldwide. It is found to be most severe in countries like China and India, where more then 60 million people are at risk. Besides the consumption of tea, common causes of excessive intake of fluoride are the inhalation of fluoride fumes in the chemical industries and the fluoridation of drinking water.