The scientists then took a look at the intestines of the animals to measure bacteria and inspected the liver to measure fat deposits.
Mice who consumed the black and grean teas had less of the bacteria associated with the obesity and more of the bacteria linked with lean body mass.
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However, only those that consumed the black tea had more Pseudobutyrivibrio, a bacteria that could help explain the difference between how black tea and green tea change energy metabolism, scientists say.
"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," said lead author Susanne Henning in a statement. "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."
Researchers believe both teas have more than antioxidant benefits but gut microbiome ones, too.
"For black tea lovers,” Henning said, “there may be a new reason to keep drinking it."
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