22 April 2018
Thought I’d share one of my obsessions on the blog today- green tea! I have a weakness for green tea flavoured anything (ice cream, mochi, latte, soba…and the list goes on) and everything (sencha, genmaicha, ocha, matcha…you name it) so let’s talk about the benefits of green tea!
Green tea and me; almost a love story
The benefits of drinking green tea are well known- namely anti-cancer, anti-aging, anti-inflammation. To date, there are more than 900 human, animal and laboratory studies on the health benefits of green tea including its ability to inhibit cancer development and growth. Where the skin is concerned, topical green tea has been shown to protect against cancer, sun damage, inflammation and reverse signs of aging.
Now before you start devouring another cup of green tea ice cream or slather green tea bags on your face, let’s first examine the science of topical green tea.Read on to see some of my own pictures too!
Gyukuro tea, from a tea salon in Tokyo. One of my must visits whenever I'm back in this city
The use of topical green tea in dermatology is an exciting development ever since green tea was found to reverse the damage from UV rays on the skin. The use of naturally occurring botanical products like green tea and vitamin C is also particularly appealing to well-informed consumers as an alternative way to protect themselves. Compared to synthetic products, botanical products are regarded as safer and less toxic- but that’s a debate for another day.
The antioxidant properties of botanicals are extensively studied and have left to their uses in cancer trials and skincare. Green tea contains antioxidants called polyphenols; more specifically epicatechins, of which the most abundant and well-studied is (-)-epigallocatechin-3-gallate (EGCG) for its anti-inflammatory, sun protective, and anti-cancer properties. Several studies have also confirmed EGCG’s benefits after topical application.
Gyukuro tea leaves are grown in the shade and are covetted for the purity of their taste.
Protection against sun UV ray damage (photoaging)
UV rays from the sun are the biggest cause of aging to the skin and have been found to cause skin cancers.
Polyphenols in green tea absorb UV rays from the sun and prevent penetration of UV radiation in the skin, thereby enhancing the effect of sunscreen when used together. This helps to reduce skin damage from the sun such as pigmentation, fine lines and wrinkles.
UV rays from the sun also damage DNA, proteins and lipids in the skin. Our bodies have natural protective mechanisms to reduce damage by UV rays but when these mechanisms are overwhelmed and depleted by excessive stresses from the sun and the environment, antioxidants can enhance these protective mechanisms.
Tsujiri in Gion, Kyoto. No yummier way to load up on antioxidants!
Remember Hugh Jackman’s PSA forsunscreen and sunprotection? The sun-loving actor was a victim of basal cell carcinoma, a type of skin cancer caused by the sun’s harmful UV rays. In fact, due to the aggressive nature of this skin cancer, Jackman has had skin cancer removed at least 6 times.
Besides basal cell carcinoma, the sun’s UV rays play a big role in the cause of another type of skin cancer called squamous cell carcinoma. Our DNA is a major target for UV rays and this leads to DNA damage i.e. mutation and when unchecked, this leads to the development of cancer.
EGCG in green tea has been shown to prevent cancer initiation and growth by multiple pathways including free radical neutralisation and inhibiting cancer spread.
Higashiya in Ginza, Tokyo, is another must visit for tea connoisseurs
Besides their antioxidant and protective benefits, polyphenols have been found to stimulate collagen formation and slow down the age-related breakdown of collagen, thereby maintaining skin texture and thickness.
Inflammation in tissue has been identified as one of the causes that lead to cancer and depletes our body’s antioxidant reserves. Green tea has been found to mitigate inflammation through various pathways and replenish our antioxidant reserves.
Polyphenols in green tea are well known for their antioxidant properties. Besides neutralising free radicals which damage structures in the skin which give rise to signs of aging,
UV rays also cause the formation of free radicals which damage cell structures like proteins and lipids.
Oh that feeling when your green tea ice-cream is bigger than your head!
Topically applied green tea has shown to provide better protection against UV rays than when consumed orally. A study in 2001 showed that topical green tea blocked UV ray infiltration and restored the skin’s depleted antioxidant levels after exposure to sunlight.
Oily skin and acne
As mentioned in my previous post (here), green tea emulsion has been found to reduce sebum secretion. Several studies have also shown that topical green tea also improves acne severity.
That’s amazing! Does this mean I should start including green tea in my skincare regime? How do I go about it?
So here’s the catch- the benefits of topical green tea is not about tea itself-it is the polyphenols i.e. the active ingredient that count. This means that the concentration of green tea (which is more often quoted than the polyphenol content) is not useful to us. Unfortunately, the variability of green tea preparations across different places also means that the polyphenol content in tea cannot be easily measured.
However, the flip side is that green tea and polyphenols have been found to be very safe to be applied topically. My take on this is: welcome green tea in your skincare routine. While we wait for more stringent ways to quantify the constituents of green tea, it is a safe skincare ingredient to start with. Now excuse me while I tuck into my cup of green tea…
Skin photoprotection by natural polyphenols: anti-inflammatory, antioxidant and DNA repair mechanisms. Nichols JA, Katiyar SK. Arch Dermatol Res. 2010 Mar;302(2):71-83
Green tea polyphenolic antioxidants and skin photoprotection. Katiyar SK, Elmets CA. Int J Oncol. 2001 Jun;18(6):1307-13.
Protective mechanisms of green tea polyphenols in skin. OyetakinWhite P, Tribout H, Baron E. Oxid Med Cell Longev. 2012;2012:560682.