Green tea continues to offer a plethora of therapeutic benefits for many tea drinkers. But in knowing what the valuable components of green tea has to offer, those looking for a little extra boost of the good stuff have started turning to more concentrated doses in the form of green tea extract. Recently, however, green tea extract has gained some notoriety as cases of adverse health effects have come to light after consumption by some individuals.
Green tea extract is a derivative of the tea plant and used in dietary and fitness supplements. This extract contains a much more concentrated dose of the polyphenol Epigallocatechin Gallate, or EGCG, which is part of what makes drinking normal green tea so beneficial for everyone. At a cellular level, EGCG may prevent or reduce the severity of cancer, but is also especially regarded for its ability to increase the body’s metabolism. As a result, green tea is often turned to for its perceived benefits in weight loss through fat reduction and thus why its extract is often used in dieting supplements.
The problem therein is the dosing to which people are submitting themselves. A cup of green tea, on average, will contain about 180mg of EGCG. Enjoying even up to 8 cups of green tea everyday is not unusual for many people and, in most cases, is great for getting the most out of what it has to offer. Bear in mind, most tea drinkers will draw out their consumption of tea from morning to evening, giving the body time to process the tea as it needs to. The slow and continuous intake of green tea throughout the day is utilised by the liver to increase the metabolism of fats, otherwise known as the thermogenic effect.
However, in the case of supplements, like capsules and powders, dosing levels of EGCG can range. A “low” dosage would be the equivalent of drinking 1-2 cups of green tea, all the way up to very high dosing, which can sit in the 800-1600mg range. When taken in one go this dose is basically the equivalent of chugging nearly 4 litres of green tea at once. Test subjects that have been exposed to these high doses have reported nausea and other discomfort. Unfortunately, the side effects of sudden spikes in EGCG to the liver have proven to be more harmful in a handful of cases. Considered as a toxic dose, these levels of EGCG can overwhelm the liver as well as induce toxicity in the kidneys and intestine. As membranes of these organs get damaged, the toxic levels of EGCG can then enter the bloodstream, leaving high concentrations in the blood causing further molecular and cellular damage. In many instances, toxic dosing of EGCG has led to requiring liver transplants, or death.
The problem of too much EGCG entering the body’s system in toxic amounts is further exacerbated by not eating before taking green tea extracts. How much of a drug that remains unchanged by the time it is absorbed into the circulatory system is referred to as bioavailability. Fasting whilst using green tea supplements was found to increase the bioavailability of EGCG, thus ensuring most of the dosage was reaching the liver, for better or for worse. Whilst maintaining a healthy diet and eating regularly could alleviate this effect, many dieting supplement labels recommend very little to no eating when using the product. Fasting may prove less detrimental when consuming low dose supplements but, judging by the available research, could prove to be quite damaging when using high doses of green tea extract.
This blog post has only taken into account the research surrounding concentrated doses of EGCG. People thinking about using dieting supplements with green tea extract should also take into consideration any other chemical components that are also on the ingredients list. Things like caffeine (which is also present in green tea extract), appetite suppressants, and garcinia cambogia extracts may also increase any risk factors when combined with EGCG. In cases where liver failure has occurred the cause cannot necessarily be narrowed down to just one element in a supplement. Experts have suggested that sometimes it might just be a matter of an individual being unable to cope with the combination of chemical reactions.
All of this information aside, regular tea drinkers and those who want to drink more tea should not be deterred from enjoying copious cuppas. As mentioned, drawing out the consumption of green tea throughout the day is a healthy practice and recommended to benefit from the nutritional components. The average individual would not guzzle 4 litres of green tea in one go and as such should not be consuming supplements with the equivalent concentrated dose of green tea extract. About 400mg of EGCG is enough to start conjuring negative effects on the body. In spite of this, supplement brands claim the fat burning potential rests in the realm of 400-500mg of EGCG. Scientific data has shown that just having a cup of tea with breakfast, lunch, and dinner is enough to start burning calories (of course coupled with a healthy diet and physical activity).
The old adage of everything in moderation is definitely applicable to green tea extracts. For anyone embarking on a diet regime and thinking of using this supplement, consider first talking to a qualified health care practitioner or a pharmacist.
Or for an alternative, intensely green tea hit, maccha is another excellent option. As a powdered green tea, it offers a more concentrated amount of health properties when compared to standard loose leaf tea, but is a more natural concentration than green tea extract. Learn more here.
Everyone should continue to enjoy their green tea in the confidence that it has been an exceptional source of nutrition for at least 4000 years. Green tea extracts, on the other hand, are only a fairly recent phenomenon manufactured for the purpose of offering a quick fix, which is not necessarily a sure thing. While this may seem like an ideal supplement for some, caution should always be exercised. Plus who needs a quick fix when nothing beats sipping on a refreshing and revitalising cup of pristine green tea?