Quality Without a Name

My dentist today observed (as he does each six month exam) that my teeth are stained. He asked (as he does every six months) if it’s coffee, tea, or wine. I indicate I enjoy all three, but that my drinking of 60-100 oz of tea per day is the most likely culprit.

He mentioned as an anecdote that children from India and China had far fewer cavities due to their tea consumption, due to the fluoride content. I was aware that tea has fluoride content, and that there were even cases of fluorosis caused by excessive consumption of aged/brick teas in particular. As a huge fan of Pu-Erh, this is an important thing for me to be aware of, versus the casual drinker of teas who only partakes in younger varieties.

So, I can see this being possible, but I worried it might be a case of correlation versus causality. My personal hypothesis is that the discrepancy was more caused by the availability of sugared snacks and drinks to the American population than the presence of fluoride in tea.

It turns out that tea has two dental benefits; the first is that the acidity does a good job of killing nasty stuff in your mouth:

It found that caffeinated green tea was the best at fighting viruses, followed by caffeinated black tea. Decaffeinated blends were less effective as anti-viral agents.

Another study looked at chemicals in tea known as polyphenols. Experiments in the laboratory showed they slowed the growth of bacteria associated with bad breath.

Christine Wu, of the University of Illinois at Chicago, said: “Besides inhibiting the growth of pathogens in the mouth, black tea and its polyphenols may benefit human oral health by suppressing the bad-smelling compounds that these pathogens produce.”

That’s pretty neat. Slightly denser material talks about the fluoride aspect in this scientific summary:

Tea plants accumulate fluoride in their leaves. In general, the oldest tea leaves contain the most fluoride (9). Most high quality teas are made from the bud or the first two to four leaves—the youngest leaves on the plant. Brick tea, a lower quality tea, is made from the oldest tea leaves and is often very high in fluoride. Symptoms of fluoride excess (i.e., dental and skeletal fluorosis) have been observed in Tibetan children and adults who consume large amounts of brick tea (10, 11). Unlike brick tea, fluoride levels in green, oolong, and black teas are generally comparable to those recommended for the prevention of dental caries (cavities). Thus, daily consumption of up to one liter of green, oolong, or black tea would be unlikely to result in fluoride intakes higher than those recommended for dental health (12, 13). The fluoride content of white tea is likely to be less than other teas, since white teas are made from the buds and youngest leaves of the tea plant. The fluoride contents of 17 brands of green, oolong, and black teas is presented in the table below (12). These values do not include the fluoride content of the water used to make the tea. For more information, see the separate article on Fluoride.

Anyway, I guess the end result is I didn’t find a conclusive result, but I’ll keep on staining my teeth.