Green tea in dermatology – myths and facts

Abstract

Summary Green tea consumption has a long tradition in Asian countries – especially China. The epidemiologically and experimentally observed anticarcinogenic and antiinflammatory effects of green tea have led to the implementation of green tea extracts in multiple therapeutic applications – both in dermatological and cosmeceutical preparations. The most abundant evidence exists for the anticarcinogenic and chemopreventive effect of green tea or its major constituent epigallocatechin‐3‐gallate. Almost equally evident is the effect in infectious diseases such as cutaneous viral infections. For external genital warts, a topical ointment with green tea extracts was licensed in the USA in 2010, and recently also in Europe. Experimental evidence pinpointing the block of central signal transduction factors in inflammatory mechanisms has led to the evaluation of catechins in inflammatory disorders such as atopic dermatitis. The belief of green tea as a “wonder weapon” against diseases dates back thousands of years. According to a Chinese legend, ancient Emperor Shen Nung noted a delightful aroma after some leaves of a nearby tree had fallen into boiling water. He immediately proclaimed the new “drink” as “heaven‐sent”, starting the belief – persisting until today – of green tea as a medication from nature against many different diseases. This review summarizes biological effects and clinical implications of green tea.

Green tea moisturizer improves skin hydration in elderly

“…(25) Polyphenols in green tea may inhibit the activity of collagenase and increase the biosynthesis of collagen in fibroblasts to further protect the skin from free radicals. (9,26,27) Moisturizers protect the skin through occluding the TEWL process by creating a protective layer above the stratum corneum. Another mechanism is by increasing water absorption into the stratum corneum (humectant), and filling the gap between desquamating keratinocytes to create a softer skin (emollient).…”

A Randomized Controlled Trial of Green Tea Beverages on the in vivo Radical Scavenging Activity in Human Skin

“…Sinecatechins (green tea extract) ointment has been found effective in the therapy of condylomata accuminata, being the first botanical drug approved for prescription by the US Food and Drug Administration [70]. Similarly, the topical administration of green tea extract has yielded promising results in the treatment of rosacea, acne, and atopic dermatitis [70].…”

“…Sinecatechins (green tea extract) ointment has been found effective in the therapy of condylomata accuminata, being the first botanical drug approved for prescription by the US Food and Drug Administration [70]. Similarly, the topical administration of green tea extract has yielded promising results in the treatment of rosacea, acne, and atopic dermatitis [70]. However, as evidence arises that orally administered green tea may exert biological effects in the skin, further research is needed to evaluate the effectiveness of green tea supplementation in the treatment and prevention of dermatological conditions, especially those associated with oxidative stress.…”

Alternative Medicine for Hair Loss

“…Apart from these diseases, it can be used to prevent or treat AGA by selectively inhibiting 5α-reductase activity. Catechins, a group of very active flavonoids, are a major component of green tea representing 60-80% of all polyphenols [44,45]. There are four major catechins in green tea: epigallocatechin-3-gallate (ECGC), epigallocatechin (EGC), epicatechin gallate, and epicatechin [46,47].…”

“…There are four major catechins in green tea: epigallocatechin-3-gallate (ECGC), epigallocatechin (EGC), epicatechin gallate, and epicatechin [46,47]. ECGC is the most highly bioactive catechin among these constituents [45]. In a study, EGCG was found to cause significant human hair follicle elongation ex vivo.…”