
30 Aug 2013 Black tea may help prevent tooth decay
The scientists say that consuming at least three cups of black tea a day helps to fight two key strains of bacteria, Lactobacillus and Strepococcus mutans, which are both linked tooth decay and gum disease.
Lead researcher Dr Carrie Ruxton, whose results are published in the British Nutrition Foundation’s Nutrition Bulletin, said: “Evidence specific to black tea suggests that three to four cups a day could help to reduce levels of bacteria in the mouth.
“I’m sure this news is set to be welcomed by dentists and hygienists alike as they continue to educate the nation on the need for greater oral care.”
Scientists found that black tea continued to fight tooth decay, even if people added sugar to it. Green tea has also shown similar benefits and also prevents bad breath by destroying compounds in the mouth that lead to both bad breath and tooth decay.
Ruxton explained that when bacteria in the mouth reacts to carbohydrates in food, it creates acid, which in time breaks down the tooth enamel, causing tooth decay and the need for fillings. Black tea helps to combat this because it reduces the amount of harmful bacteria in the mouth, which lessens the quantity of plaque acids released when eating.
Black and green tea contains catechins, disease-fighting flavonoids, which have anti-bacterial properties. A review of previous related studies added that green tea says it can help burn fat because it facilitates greater expenditure of energy.
Dr Tim Bond, spokesman for the Tea Advisory Panel explained that until now, relatively little has been known about the benefits of tea in reducing dental cavities and tooth decay.
He added: “This benefit is thought to be due to a reduction in inflammation in the oral cavity and prevention of the adhesion and growth of bacteria linked to periodontal disease.
“In terms of weight management, Dr Ruxton’s published review found further supporting effects for green tea when consumed by overweight and obese adults.
“How green tea might contribute to weight management needs further research, but this latest research review suggests that the catechin ingredients could impact on satiety and thermogenesis and may counter the reductions in metabolism seen when body weight falls.”
He explained that the latest research just adds to the wealth of things we already know about tea, including the fact that is is good for heart health and reducing certain risks of cancers.
Abstract of the study:
Tea is the most commonly consumed beverage in the world, after water. Associations between regular tea drinking and a reduced risk of coronary heart disease are well established. The mechanism may relate to bioactive compounds found in tea, which exert anti-arteriosclerotic, anti-oxidative and anti-inflammatory effects. However, evidence for other diverse health benefits is emerging.
The aim of this review was to evaluate research on three new areas of interest in relation to tea drinking: (1) weight management (and glycaemic control); (2) oral health; and (3) gut health.
Databases were searched for meta-analytical, human intervention and epidemiological studies published between 1990 and 2013. For weight management, modest, positive effects were found for green tea when ingested by overweight/obese adults, possibly related to thermogenic effects.
Epidemiological studies indicate that tea drinking in general may protect against tooth loss, certain oral/digestive cancers and Helicobacter pylori infection, although the studies were few in number with differing methodologies.
A growing body of mechanistic studies suggests that tea has anti-cariogenic, anti-adhesive, anti-bacterial and possible pre-biotic effects – all with the potential to impact positively on the pathogenesis of chronic diseases.
Clearly, larger trials are needed to confirm these effects in humans and establish optimal intakes. In the meantime, tea drinking appears to be a simple and beneficial way to support health.
Journal Reference:
Emerging evidence for tea benefits
Article first published online: 16 AUG 2013; DOI: 10.1111/nbu.12040
Nutrition Bulletin; Volume 38, Issue 3, pages 287–301, September 2013