While the health benefits of green tea have long been known, nutrition experts now say English Breakfast tea is also good for us.
They found that drinking black tea changes bacteria in the gut. The percentage of bacteria associated with obesity decreased, while those associated with lean body mass increased.
Study co-author Dr Zhaoping Li, from the University of California Los Angeles, said the findings suggest that the health benefits of both green tea and black tea go beyond their antioxidant benefits.
She said: “For black tea lovers, there may be a new reason to keep drinking it.”
Weight loss diet: Researchers say a daily cup of tea changes the way body breaks down fat
Previous studies indicated that chemicals in green tea called polyphenols are absorbed and alter the energy metabolism in the liver.
But the new findings show that black tea polyphenols, which are too large to be absorbed in the small intestine, stimulate the growth of gut bacteria and also boost energy metabolism in the liver, helping to break down fat.
Professor Susanne Henning, who led the study at UCLA Centre for Human Nutrition, said: “It was known that green tea polyphenols are more effective and offer more health benefits than black tea polyphenols since green tea chemicals are absorbed into the blood and tissue.
“Our new findings suggest that black tea, through a specific mechanism through the gut microbiome, may also contribute to good health and weight loss in humans.”
For black tea lovers, there may be a new reason to keep drinking it
She added: “The results suggest that both green and black teas are prebiotics, substances that induce the growth of good microorganisms that contribute to a person’s wellbeing.”
Bodies representing the tea industry in the UK welcomed the new research, which was tested on mice.
Bill Gorman, executive chairman of the United Kingdom Tea and Infusions Association, said: “Black and green tea have a number of nutritional values and benefits which is something the Chinese established about 5,000 years ago.
“However, what we have now is the scientific rigour and expertise to show what tea actually does in the body.”
Weight loss diet: Nutrition experts said English Breakfast tea is good for us
The new study is published in the European Journal of Nutrition. Britain is in the midst of an obesity crisis that is costing the NHS billions of pounds each year.
The nation’s obesity “timebomb” has been blamed for sharp rises in Type 2 diabetes and other serious health conditions. Latest UK figures show that some 67 per cent of men and 57 per cent of women are now either overweight or obese.
But the problem is also becoming acute in children. Some 19 per cent of children aged between 10 and 11 are now obese while a further 14 per cent are overweight.
Of children aged between four and five, 9 per cent are classed as obese and 12 per cent are overweight.
In the new study, four groups of mice received different diets – two of which were supplemented with green tea or black tea extracts.
Weight loss diet: Drinking black tea changes bacteria in the gut
The diets were low-fat and high sugar, high-fat and high-sugar, high fat, high-sugar and green tea extract and high-fat, high-sugar and black tea extract.
After four weeks, the weight of mice given green or black tea extracts dropped to the same levels as the mice that received the low-fat diet during the study.
The researchers also measured gut bacteria in the mice and fat deposits in their livers.
In the mice that consumed either type of tea extract, there was less of the type of bacteria associated with obesity and more of the bacteria linked to lean body mass.
However, only the mice that consumed black tea extract had an increase in a type of bacteria called pseudobutyrivibrio, which could help explain the difference between how black tea and green tea change energy metabolism.
Published at Thu, 05 Oct 2017 23:01:00 +0000