From Science Daily:
Although green tea is enjoyed by millions for its numerous health benefits, University of California, Irvine researchers have discovered that excessive consumption adversely affected development and reproduction in fruit fly populations.
It’s unclear whether overconsumption could have the same impact on humans, but the findings suggest caution when using green tea, or any natural product, in high doses. Nutraceuticals such as green tea, while growing in popularity, are largely unregulated. Study results appear in the Journal of Functional Foods.
A UCI team led by Mahtab Jafari, associate professor of pharmaceutical sciences, investigated the effects of green tea toxicity on Drosophila melanogaster development and reproduction. Embryos and larvae were subjected to various doses of green tea polyphenols with the following results:
Larvae exposed to 10 milligrams of green tea were slower to develop, were born smaller and exhibited a dramatic decline in the number of emerged offspring. Ten milligrams of green tea made the flies more susceptible to starvation and heat stress but protected them against dehydration. Female offspring showed decreased reproductive output and a 17 percent reduction in lifespan; males were unaffected. Ten milligrams of green tea caused morphological abnormalities in reproductive organs, such as testicular and ovarian atrophy.
Jafari believes that high doses of green tea may cause “too much” apoptosis, or cell death, but in this study, she said, they did not evaluate mechanisms, which is the focus of her current research.
Derived from the plant Camellia sinensis, green tea is popular worldwide for its purported brain and…