Polyphenol Content of Bottled Teas "Surprises" Scientists

Bottled teas may not be as healthful as some consumers might think, according to research presented at this week...s national meeting of the American Chemical Society (ACS).

Researchers at the biotechnology company WellGen (North Brunswick, NJ) assessed the polyphenol content of 49 branded bottled teas, as NPR reports, and the results were surprising: 'Out of 49 samples, half of the bottle teas contain less then 10 milligrams of polyphenols,' lead researcher Shiming Li told NPR.

ACS states that an average cup of brewed black or green tea may contain between 50 and 150 mg of polyphenols, yet in six bottled teas purchased from supermarkets, Li measured polyphenol contents 81, 43, 40, 13, 4, and 3 mg per 16-ounce bottle.

'Someone would have to drink bottle after bottle of these teas in some cases to receive health benefits,' said Li. 'I was surprised at the low polyphenol content. I didn...t expect it to be at such a low level.' Half of the teas contained what Li considered 'virtually no' antioxidants.

The researchers used high-performance liquid chromatography (HPLC) to measure polyphenol content in what WellGen is calling 'the first measurements of polyphenols in bottled tea beverages.' WellGen hopes that this research will encourage future use of the technology to better consumer understanding of nutrition.