Green Tea Effects on Cognition, Mood and Human Brain Function

Green tea effects on cognition, mood and human brain function: A systematic review.

Abstract
BACKGROUND:
Green tea (Camellia sinensis) is a beverage consumed for thousands of years. Numerous claims about the benefits of its consumption were stated and investigated. As green tea is experiencing a surge in popularity in Western culture and as millions of people all over the world drink it every day, it is relevant to understand its effects on the human brain.

PURPOSE:
To assess the current state of knowledge in the literature regarding the effects of green tea or green tea extracts, l-theanine and epigallocatechin gallate both components of green tea-on general neuropsychology, on the sub-category cognition and on brain functions in humans.

METHODS:
We systematically searched on PubMed database and selected studies by predefined eligibility criteria. We then assessed their quality and extracted data. We structured our effort according to the PRISMA statement.

OUTCOME:
We reviewed and assessed 21 studies, 4 of which were randomised controlled trials, 12 cross-over studies (both assessed with an adapted version of the DELPHI-list), 4 were cross-sectional studies and one was a cohort study (both assessed with an adapted version of the Newcastle-Ottawa assessment scale). The average study quality as appraised by means of the DELPHI-list was good (8.06/9); the studies evaluated with the Newcastle-Ottawa-scale were also good (6.7/9).

CONCLUSIONS:
The reviewed studies presented evidence that green tea influences psychopathological symptoms (e.g. reduction of anxiety), cognition (e.g. benefits in memory and attention) and brain function (e.g. activation of working memory seen in functional MRI). The effects of green tea cannot be attributed to a single constituent of the beverage. This is exemplified in the finding that beneficial green tea effects on cognition are observed under the combined influence of both caffeine and l-theanine, whereas separate administration of either substance was found to have a lesser impact.

10.1016/j.phymed.2017.07.008

 

Green Tea Extract Linked to Tinnitus
Having a cup of piping hot green tea feels good for the body as well as the soul. But new evidence suggests that we should moderate our intake of the powerful antioxidants found in green tea.

Green tea extract, which is found mostly in supplements, reportedly causes ringing in the ears. According to a Consumer Reports article dated March 21, 2017, the same supplement many use for weight loss can have serious, even fatal side effects. Green tea extract, according to the article, can reduce the absorption of iron, exacerbate glaucoma, elevate blood pressure and heart rate and cause liver damage.

According to a 2014 American College of Gastroenterology report, you really can get “too much of a good thing.” Green tea has a whole host of health benefits associated with it. One of the main components of green tea are the antioxidants or catechins, which provide the health benefits we hear about almost daily.

Apparently, though, when too much green tea is consumed, like the amounts found in green tea extract, those very same antioxidants can prevent the body from metabolizing food and creating energy. This can lead to jaundice, hepatitis and liver failure. Ringing in the ears or tinnitus is a subsequent side affect. Because green tea extract is used in supplements, the concentration is too high, making them something to avoid. But not all supplements are bad. Ones like Lipo-Flavonoid, have been widely recognized for more than half a century.

Some tinnitus sufferers agree that an increase in green tea exacerbates their tinnitus symptoms. On a TinnitusTalk.com forum page, where a member discussion revolves around alternative treatments and research, it is suggested that cutting out green tea and caffeine for at least three months can alleviate symptoms. Members noted that caffeine and alcohol could also be potential culprits.

Green tea is not the enemy. It still helps improve mental alertness, cognitive thinking and increase urine output. It can also help with a multitude of illnesses like depression, headaches, stomach disorders, bone loss, certain cancers and Parkinson’s disease, just to name a few.

It is still a very good thing, but as with all good things, moderation is key. Stay away from the supplements and anything with green tea extract as the concentration is too high. What’s more, you can actually overdose from having toxic levels in your system, which can lead to death, according to a WebMD article.

If you are a tinnitus sufferer, you might want to give it the three month try and see if the ringing in your ears subsides or not. In the meantime, supplements like Lipo-Flavonoid, were specifically developed to reduce ringing in the ears. Plus, it’s the No. 1 doctor recommended ear health supplement. There’s even a nighttime version, which includes melatonin to assist with sleep disruptions.

 

So what's the green tea brand that has been more effective to reduce tinnitus or hyperacusis?

 

You cannot count on green tea to do any of that, but it's still very healthy if the quality is good. If it worked we all would be slamming down green tea on this site.

Cheap teabags are pretty much poison, extreme levels of fluoride in them. The least amount of fluoride is in white tea or japanese green tea, China is more polluted and the tea bush is very good at drawing all kinds of bad stuff from the soil.

There's special tea that has artificially increased levels of GABA. Though expensive, this would probably be the best kind

The world of green tea is wonderful but it's unfortunately a pretty expensive hobby