According to boffins at the University of Derby, some cheap supermarket-own tea bags contain dangerously high levels of fluoride - a chemical that can cause damage to teeth, bones and muscles.
Fluoride is essential for strong bones and teeth, which is why it's commonly found in toothpaste. But over 4mg per day can cause all sorts of worrying long term issues.
A study by PHD student Laura Chan, Professor Aradhana Mehra and Professor Paul Lynch from the University of Derby compared 38 tea products from supermarket 'value' brands. They discovered that four daily brews made using cheap tea bags from Tesco, Sainsbury's, Asda and Morrisons provided 75% to 120% of your daily intake of fluoride.
Now they're calling for fluoride levels to be stated on food packaging.
More expensive brands like PG Tips, Twining's and Typhoo have lower levels, but it's specialist brands like Oolong and Pu'er that contain the smallest amounts of fluoride (just 0.7 mg per litre).
Ms Chan said, "The tea plant, Camellia sinensis, is a fluoride accumulator, with mature leaves accumulating most of the fluoride. Excessive intake of fluoride can cause a variety of health problems including joint pain, muscle weakness, osteoporosis, brittle teeth, kidney problems and has even been linked to cancer."
She added, "People may be drinking excessive volumes of tea in addition to other dietary sources of fluoride and may not realise these potential health implications."
So the answer's pretty simple really...treat yourself to some proper good quality tea bags instead of the cheapest 'bottom shelf' options. They will contain less fluoride and probably taste nicer too. Simples.
What do you think?
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