Green tea has changed a few skin measurements in small clinical trials. Human studies have yet to show a reliable visible skin benefit from an ordinary cup.
Green tea appears in skin advice so often that the conclusion can seem settled before we look at the research. It contains antioxidants, while UV exposure and acne both involve processes that catechins may influence. Surely drinking green tea must help.
The biology gives researchers a reason to investigate green tea. It does not tell us whether drinking it produces a visible change in human skin.
So far, human trials have reported small changes in selected measurements, particularly redness after controlled UV exposure. They have not shown a reliable visible benefit from a usual cup. Much of the research used standardised drinks or concentrated extracts containing defined, and sometimes very high, catechin doses.
Can Results From Green Tea Extract Apply to Brewed Tea?
Green tea contains polyphenols called catechins. The one discussed most often is epigallocatechin gallate, usually shortened to EGCG.
Once swallowed, catechins pass through the gut and liver, where much of the original material is converted into metabolites. Human studies have detected these metabolites in skin. However, the quantity and chemical form that reach skin differ from what was present in the drink or capsule. A high-dose extract study cannot tell us what a usual cup will do unless the catechin exposures are comparable.
| What participants consumed | Example from human skin research | What we can learn |
|---|---|---|
| Brewed green tea | Three cups daily for two weeks | Whether that tea changed the specific skin measurement used in the study |
| Standardised catechin drink | A research drink providing 1,402 mg of catechins each day | What a controlled, high catechin intake did under trial conditions |
| Green tea extract | Capsules providing a defined EGCG dose | What that concentrated dose did, including any adverse effects |
| A usual cup made at home | Catechin content varies with the tea, amount used and brewing method | The dose cannot be assumed to match a drink or extract used in a trial |
Similar confusion appears in claims that drinking more water produces better-hydrated skin. Consumption alone does not establish how much reaches the skin or whether the visible result changes.
Does Drinking Green Tea Protect Skin From UV Damage?
Researchers often measure UV-induced redness because it can be produced and quantified under controlled conditions. A small area of skin receives a chosen UV dose, then redness is measured later. The test captures one part of the skin’s response rather than months or years of ordinary sun exposure.
A 2021 systematic review and meta-analysis found that oral green tea catechins reduced redness after low experimental UV doses. The effect appeared around 1.25 to 1.30 times the minimal erythema dose, which is the lowest dose that produces visible redness. Only a small number of trials contributed to the analysis.
One trial included 60 women who consumed a research drink containing 1,402 mg of catechins each day for 12 weeks. UV-induced redness fell by 16% after six weeks and by 25% after 12 weeks. Read the study
Those findings apply to a standardised, catechin-rich drink. The trial did not test one or two cups of ordinary tea.
In another randomised trial, participants took 1,080 mg of green tea catechins with vitamin C each day for three months. The supplement did not reduce UV-induced redness or the measured inflammatory responses. Read the study
Redness also tells us less about UV injury than many headlines suggest. UV radiation can damage DNA in skin cells, while the visible redness develops partly through inflammatory signals released afterwards. A catechin preparation could affect those signals without preventing the earlier DNA injury.
Researchers tested this directly by measuring cyclobutane pyrimidine dimers, a type of DNA lesion caused by UV radiation. Oral green tea catechins did not reduce these lesions after higher-dose simulated sunlight. Read the study
I would not describe oral green tea as sun protection. Sunscreen reduces the amount of UV that enters the skin. These trials examined selected responses after UV exposure had occurred. Less experimental redness does not mean that someone can spend longer in the sun safely.
Less redness after UV exposure does not necessarily mean less skin damage.
Does Drinking Green Tea Help Acne?
One oral trial involved 80 women aged 25 to 45 with moderate to severe acne. Participants took either a decaffeinated green tea extract or placebo for four weeks. The daily extract dose contained 856 mg of EGCG.
Women taking the extract developed fewer inflammatory lesions on the nose, around the mouth and on the chin than women taking placebo. Total facial lesion counts did not differ significantly between the groups, and 64 participants completed the trial. Read the study
The study did not test brewed green tea, and the improvement was confined to selected facial areas during a four-week trial. It cannot support using a cup of tea as an acne treatment.
European safety reviewers found significant increases in liver enzymes in supplement studies that provided at least 800 mg of EGCG per day. The acne trial used 856 mg. Although that trial did not establish liver injury, I would not copy its dose for cosmetic self-treatment.
A systematic review and meta-analysis found that topical green tea preparations reduced inflammatory and non-inflammatory acne lesions. The oral studies did not show a significant reduction in total acne lesions. This was an indirect comparison across separate trials, rather than a study assigning participants to a topical product or a drink.
Topical delivery depends on formulation. EGCG breaks down readily, while the product base controls how much can enter follicular skin. Applying tea to the face or choosing any product with green tea on its ingredient list does not reproduce a clinical formula.
Does Drinking Green Tea Prevent Wrinkles?
Laboratory studies provide reasons to investigate green tea catechins. UV exposure activates processes involved in collagen breakdown, as I explain in What Is Skin Aging, Really?. Catechins can influence some of them in cells and experimental models.
The clinical question is whether an oral green tea preparation improves photoaged human skin.
In a two-year, double-blind trial, oral green tea polyphenols did not improve the clinical appearance or microscopic features of photoageing more than placebo at the end of the study. Read the study
Other trials combined oral supplements with topical green tea or used multi-ingredient drinks, so any change cannot be assigned to oral green tea alone.
Cell research can explain how an ingredient might work, but it cannot demonstrate that a drink reduces wrinkles. If wrinkles are your main concern, my comparison of retinol and vitamin C for skin ageing examines topical ingredients that have been studied for visible skin outcomes.
Can Green Tea Make Skin Glow?
“Glow” has no fixed clinical definition. It may refer to texture, pigmentation, hydration or the way light reflects from the skin. A study must measure the claimed feature before it can support a visible glow claim.
In one small trial, 32 people drank three cups of Benifuuki green tea, Yabukita green tea or water each day for two weeks. Both teas increased radical-scavenging activity measured in the skin by about 28% to 29% compared with water. Read the study
The test assessed how skin handled a laboratory-generated radical. The researchers did not measure facial clarity, smoothness or luminosity. We can report the antioxidant measurement, but we cannot rename it “glowing skin.”
Pro tip: When a product claims to improve skin through antioxidants, check what the study measured. Antioxidant capacity is a biochemical result. A visible claim needs photographs, clinical grading or an instrument that measures the relevant feature.
Are Green Tea Extract Supplements Safe?
Ordinary green tea and concentrated green tea extracts have different safety profiles.
The European Food Safety Authority found that catechins from green tea infusions are generally considered safe. In supplement trials, EGCG doses at or above 800 mg per day were associated with significant increases in liver enzymes. The available studies did not allow EFSA to identify a supplemental dose that would be safe for everyone.
Australia’s Therapeutic Goods Administration has also warned that green tea extracts can cause rare and unpredictable liver injury. Most Australian reports involved concentrated extracts, and many products contained several ingredients. The TGA considers harm from ordinary green tea consumption unlikely for most people.
A capsule may look like a convenient way to obtain more catechins, but higher exposure does not guarantee a better skin result. The risk can change as the dose rises.
I would avoid a proprietary blend that does not state its EGCG content. Without the dose, you cannot compare the supplement with the clinical trials or the safety assessment. Anyone with liver disease, abnormal liver tests or regular medicines should ask a doctor or pharmacist before taking a concentrated green tea extract.
Would I Drink Green Tea for My Skin?
I would drink green tea because I enjoy it, not because I expect it to treat acne or prevent wrinkles.
I drink green tea because I enjoy it. Current human research would not persuade me to add it for a skin concern, and I would not buy a concentrated extract for cosmetic benefits.
The studies of ordinary tea are too small and short to support a visible skin claim. Trials using standardised drinks or extracts cannot fill that gap because their doses and preparations differ from a usual cup.
When you see a skin claim about green tea, check what people consumed and what the study measured. A trial using a capsule and recording a laboratory biomarker cannot establish a visible benefit from brewed tea.
Research Used
- Di Sotto, A. et al. (2022). Efficacy and safety of oral green tea preparations in skin ailments: A systematic review of clinical studies. Nutrients, 14(15), 3149.
- Kapoor, M.P. et al. (2021). Green tea catechin association with ultraviolet radiation-induced erythema: A systematic review and meta-analysis. Molecules, 26(12), 3702.
- Heinrich, U. et al. (2011). Green tea polyphenols provide photoprotection, increase microcirculation, and modulate skin properties of women. The Journal of Nutrition, 141(6), 1202–1208.
- Farrar, M.D. et al. (2015). A randomized controlled trial of green tea catechins in protection against ultraviolet radiation-induced cutaneous inflammation. The American Journal of Clinical Nutrition, 102(3), 608–615.
- Farrar, M.D. et al. (2018). Oral green tea catechins do not provide photoprotection from direct DNA damage induced by higher-dose solar-simulated radiation. Journal of the American Academy of Dermatology, 78(2), 414–416.
- Megow, I. et al. (2017). A randomized controlled trial of green tea beverages on the in vivo radical-scavenging activity in human skin. Skin Pharmacology and Physiology, 30(5), 225–233.
- Lu, P.H. and Hsu, C.H. (2016). Does supplementation with green tea extract improve acne in post-adolescent women?. Complementary Therapies in Medicine, 25, 159–163.
- Kim, S. et al. (2021). The effects of green tea on acne vulgaris: A systematic review and meta-analysis of randomized clinical trials. Phytotherapy Research, 35(1), 374–383.
- Janjua, R. et al. (2009). A two-year, double-blind, randomized placebo-controlled trial of oral green tea polyphenols on photoageing skin. Dermatologic Surgery, 35(7), 1057–1065.
- EFSA Panel on Food Additives and Nutrient Sources Added to Food (2018). Scientific opinion on the safety of green tea catechins. EFSA Journal, 16(4), 5239.
- Therapeutic Goods Administration (2018). Camellia sinensis (green tea) extract.
