Health Problems Associated with Excessive Green Tea Consumption

For hundreds of years, green tea has been praised for its several health advantages. But with respect to a new research, the beverage could do more damage than good if taken in huge amounts.

In a new research presented in the Journal of Functional Foods, investigators show how exposure to extreme quantities of green tea impaired the reproductive function of fruit flies, along with the growth of their offsprings.

While it is not clear whether the beverage has the same effect on human beings, the research team says their results warrant warning towards taking huge amounts of green tea and other nutraceuticals.

Green tea is produced from fresh leaves of the Camellia sinensis plant. Because green tea is one of the least processed types of tea, it preserves the greater part of its antioxidants and polyphenols, which are identified to be mostly beneficial for health.

Earlier research has recommended green tea can help weight loss, decrease cholesterol and protect towards several illnesses, such as cancer, heart disease and Alzheimer’s disease.

However, some research have claimed adverse health effects if the drink is taken in huge doses; animal research have connected too much green tea intake to dramatic weight loss and reduced embryonic development.

Green tea ‘should be taken in small amounts’

To achieve their results, lead researcher Mahtab Jafari, and colleagues subjected embryos and larvae of fruit flies, or Drosophila melanogaster, to different doses of green tea.

Fruit flies are usually used to study human health issues due to the fact they share 75% of the same genes that trigger disease in humans.

The team identified that 10 milligrams (mg) of green tea lead to sluggish development of larvae. There was also a considerable decrease in the number and size of offspring that emerged.

Female offspring subjected to 10 mg of the beverage revealed a decrease in reproductive output, along with a 17% decrease in lifespan.

Further, the investigators identified 10 mg of green tea led to morphological irregularities in reproductive organs of the fruit flies, such as atrophy in the testicles and ovaries.

Green tea was seen to secure the flies against dehydration, but it also enhanced susceptibility to heat stress and starvation.

While the research did not evaluate the mechanisms by which green tea impacted the development and reproduction of the fruit flies, they hypothesize that higher doses of the beverage may induce excessive apoptosis, or programmed cell death, to deliver such effects.

Leaving comments on the results, Jafari states that:

“While green tea could have health advantages at low amounts, our research and some others have revealed that at higher doses, it may have adverse consequences. Additional work is required to make any clear recommendations, but we can recommend that green tea be taken in moderation.”

The research team now plans to check the effects of other nutraceuticals in fruit flies, along with pinpoint and evaluate the metabolites of natural products in the flies. “These tests will allow us to have a much better understanding of toxic doses in human beings,” notes Jafari.