Green Tea Extract may Cause Liver Damage in People with Certain Genetic Variations

Long-term consumption of high-dose green tea extract may cause liver damage in a small fraction of the population, which makes us wonder if green tea is all that healthy. Whenever we think about losing weight, a cup of hot green tea seems to top our checklist. There are numerous studies backing that cup of green tea with all the health benefits, but for some people with certain genetic variations, this cup might not be all that beneficial.

"Learning to predict who will suffer liver damage is potentially important because there’s growing evidence that high-dose green tea extract may have significant health benefits for those who can safely take it," said Hamed Samavat, senior author of the study and an assistant professor of nutrition sciences at the Rutgers School of Health Professions.

The collected data from the Minnesota Green Tea Trial, a large study of green tea's effect on breast cancer, on individuals with specific genetic variations that were more likely to display symptoms of liver stress after consuming 843 milligrammes per day of the primary anti-oxidant in green tea, a catechin called epigallocatechin gallate (EGCG).

Laura Acosta's research looked into two genetic variants that affected the production of an enzyme that breaks down EGCG.The Minnesota Green Tea Trial was chosen as it was a substantial, well-designed trial with a distinct demographic. The year-long, placebo-controlled trial enrolled over 1,000 postmenopausal women and gathered data at an interval of 3, 6, 9, and 12 months.

Early symptoms of liver damage were slightly more common than usual in women with one variant in the catechol-O-methyltransferase (COMT) genotype and highly predicted by a variation in the uridine 5'-diphospho-glucuronosyltransferase 1A4 (UGT1A4) genotype, according to a study.

After nine months of taking the green tea supplementation, those with the elevated UGT1A4 genotype had an increase in the enzyme that suggests liver stress of nearly 80%, while those with the low-risk genotype saw an increase of 30%.

"We’re still a long way from being able to predict who can safely take high-dose green tea extract," said Samavat, who noted the risk of liver toxicity is only associated with high levels of green tea supplements and not with drinking green tea or even taking lower doses of green tea extract. "Variations in this one genotype don’t completely explain the variations in liver enzyme changes among study participants. "The full explanation probably includes a number of different genetic variations and probably a number of non-genetic factors".

"Still," Samavat continued, "we do think we have identified an important piece of the puzzle and taken a step toward predicting who can safely enjoy any health benefits that high-dose green tea extract provides".

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Benefits of Green Tea

Green tea has been linked to a number of health advantages, including the prevention of many kinds of cancer, heart disease, and liver illness. Many of green tea's health benefits are linked to its catechin content, specifically epigallocatechin-3-gallate. In vitro and animal research have provided evidence for the underlying processes of green tea catechins and their biological activities. Human research on the use of green tea catechins to treat metabolic syndrome, such as obesity, type II diabetes, and cardiovascular risk factors, is currently underway.

Long-term tea catechin consumption may be protective against high-fat diet-induced obesity and type II diabetes, as well as lowering the risk of cardiovascular disease. More research that adheres to international standards should be conducted to track the pharmacological and clinical outcomes.

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Side-effects of Green Tea

Green tea, like the ying-yang, has a plethora of health claims in favor of its consumption, but due to the simple availability and increased popularity of highly concentrated green tea extracts, sometimes mixed with a more-is-better mentality, various health hazards associated with green tea use have begun to emerge. Among these dangers are the potential risk of liver damage, the possibility of interfering with prescription drugs and altering their therapeutic efficacy, and the possibility of causing harm when combined with other popular herbal therapies. And with recent research, it has been suggested that green tea can cause severe side effects, such as liver damage.

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The Right Way to Drink Green Tea

For the majority of us, green tea is an elixir that offers a healthy way of life.

• We know it is an excellent antioxidant, aids in fat burning, inhibits bad breath, defends against cardiovascular disease, and has anti-aging qualities. But does that mean we may guzzle several cups of green tea blindly every day, assuming they are doing all of the above? Not really, according to experts.
• 2 to 3 cups of green tea per day. Green tea contains a lot of antioxidants and natural plant elements, including tannins and flavonoids. Excessive consumption might induce toxicity or liver damage. So, limit yourself to two to three cups each day.
• Never drink green tea on an empty stomach: While caffeine might provide a much-needed boost to your day, it can also have an unfavorable effect on stomach balance. Instead, opt for a fruit or a cup of warm water with lemon and honey.
• Also, not immediately after meals: Many people drink green tea after daily meals, not realizing that consuming green tea right after meals will decrease nutrient absorption. This means that whatever you consume is not adequately digested because the caffeine and tannins act as impediments. This can also dilute stomach fluids, leading to poor digestion. Green tea is best consumed for 30–45 minutes, either before or after meals.
• No late-night sipping: Avoid drinking green tea late at night because it can disrupt your sleep routine and boost your stress levels.
• Reusing green tea bags is not recommended because, in addition to the horrifyingly high caffeine concentration of an old tea bag, wet tea bags are prone to microbial infestation. Don’t use it more than twice in a row. However, it is better to use green tea leaves for your cup of tea.
• Drink extra plain water. Green tea is also a diuretic, which means it may cause frequent urination. So, drink more water to keep your body hydrated.

Green tea has two sides, just like a coin; if consumed the right way, it can be beneficial for health, but just like anything in excess, even green tea in excess can do more harm than good.



Source-Medindia