Hypertension, or High Blood Pressure and Japanese Green Tea

Hypertension, or high blood pressure, is when your blood pressure is above standard.

In this article we'll jump into how Japanese Green Tea helps lower high blood pressure, and the type of tea you should look for.

This article was last modified December 11th, 2022. by Yuki

Hypertension and Japanese Green Tea

There are slightly different criteria for Hypertension depending on the country. However, in Singapore, according to MOH, a blood pressure reading of 140/90 mmHg or higher is considered high blood pressure.

Hypertension has been rapidly increasing in Singapore. According to the Singapore National Health Survey (2020), the overall prevalence of Hypertension rose from 24.2% in 2017 to 35.5% in 2020. This occurrence means that more than 1/3 of the population has Hypertension. Males have a higher hypertension rate, with 41% of the people in 2020.

While Hypertension usually causes no symptoms, it can lead to much more severe diseases in the long term.

It can also lead to diseases and conditions such as atherosclerosis, stroke, heart attack, heart failure, kidney disease or failure, vision loss, sexual dysfunction, angina, and peripheral artery disease. [3]


How effective is Japanese Green Tea in Reducing High Blood Pressure?

Several human-based studies show that green tea and its catechins can help reduce high blood pressure.

A large-scale human-based study on 2,318 people concluded that a higher frequency of drinking green tea was associated with fewer cases of high blood pressure. [4]

Another research shows that drinking 500 mg of Catechins daily for three months has reduced high blood pressure. The improvement was more evident in people with higher blood pressure.

These studies highlight the promising potential of Japanese green tea in helping high blood pressure.


How does Japanese Green Tea Reduce High Blood Pressure?

First, let's understand how blood pressure increases. An enzyme called the angiotensin-converting enzyme, or ACE has a driving effect.

ACE creates angiotensin II in your body, which acts directly on blood vessels, causing their constriction and thereby raising blood pressure. Historically, Pharmaceutical companies targeted ACRE in the 1970s to create successful medicine to treat Hypertension.

Tea Catechins work similarly to these medicines to powerfully interfere with ACE.


The Benifuki Cultivar is Especially Effective

There are four types of Green Tea Catechins in Japanese Green Tea, and EGCG is perhaps the most well-known. This recognition comes from its robust health benefits and the fact that it is the most prominent type of green tea catechin in Japanese Green tea.

While EGCG has shown effectiveness in helping Hypertension, research shows that an altered form of EGCG, the "O-methylated EGCG," is especially potent.
The O-methylated EGCG has 5-6 times the absorption rate of normal EGCG in the human body.

The Benfifuki cultivar is a relatively rare cultivar that contains high amounts of O-methylated EGCG. It is a cultivar that is more suited for oxidized tea so you may find it more commonly in the form of Black tea or Oolong tea.

However, O-methylated EGCG significantly decreases when it is oxidized. You need to find a green tea form of the Benifuki cultivar to intake O-methylated EGCG. Finding this tea may be difficult to do in Singapore.

See also: All about O-Methylated EGCG and its health benefits


If You Can't Find the Benifuki Cultivar

If you can't find the rare green tea form of the Benifuki cultivar, drinking other Japanese Green tea is also effective. As mentioned above, other green tea catechins are also effective in helping Hypertension.

The green tea catechins EGC and EGCG mentioned above help by producing NO or Nitric Oxide in the body. Nitric oxide is known to control blood pressure by widening blood vessels. This tendency is not seen in the O-methylated EGCG stated above.

Look for standard types of Japanese green tea, such as Sencha and Tamaryokucha, to maximize the amount of EGC and EGCG.


How to prepare Benifuki Green Tea

If you have chanced upon the Benifuki Green Tea, it's essential to brewing in boiling water to extract the most O-methylated EGCG.

We recommend brewing the tea under a boiling pan on low heat for roughly 5 minutes to maximize the effect. This method, however, will add to the astringency of the tea.

If you are drinking Sencha or Tamaryokucha, we recommend brewing the tea with boiling water. The catechin EGCG is a nutrient that dissolves in water at temperatures 80 degrees Celsius. Therefore cold brewing will now allow the nutrients to be enjoyed.

Author Yuki

Yuki

Yuki is the Editor-in-Chief AND Community Manager at Tealife. He bleeds Japanese Tea and loves being a part of the Japanese Tea journey of others. Writes, does events, conducts tasting sessions, drinks, drinks and drinks tea! Easily accessible - hit him up on whatsapp (+65) 85882980.


References

[1] https://www.healthhub.sg/a-z/diseases-and-conditions/735/Understanding-Blood-Pressure-Readings

[2] https://www.moh.gov.sg/docs/librariesprovider5/default-document-library/nphs-2020-survey-report.pdf

[3] https://www.heart.org/en/health-topics/high-blood-pressure/health-threats-from-high-blood-pressure

[4] 村松ら編 茶の機能 (学会出版センター)2002