Camellia sinensis (leaf extract)

Green Tea Extract

Green tea extract lowers total and LDL cholesterol by a small amount and blood pressure by about 2 mmHg in pooled trials, but it does not produce clinically important weight loss. The main caution is the liver: concentrated extracts, unlike the drink, have caused rare but sometimes severe liver injury, and EFSA found that 800 mg or more of EGCG a day raised liver enzymes in trials.

A cup of green tea and a capsule of concentrated catechins are not the same exposure, and the safety reassurance for one does not carry over to the other.

Written by

Healthy and Herbal editorial team

Reviewed by

Healthy and Herbal editors

Updated

10 October 2026

Loose green tea leaves and a cup of green tea

At a glance

Last reviewed 10 October 2026

Evidence

Moderate

Best for

Small LDL reduction

Typical form & use

Catechin extract, taken with food

Onset

4+ weeks

Safety

Rare liver injury; EFSA flags 800 mg+ EGCG a day. 2 known interactions, most serious with blood pressure medication.

Check with your medications →

What it's used for

Evidence is rated per use. The same ingredient can be strong for one thing and traditional for another.

Use	Evidence	What the research shows
Cholesterol (total and LDL)Compare remedies for heart health →	Moderate	Two meta-analyses of randomised trials found green tea catechins or green tea lower total cholesterol by about 5 to 7 mg/dL and LDL cholesterol by about 2 to 5 mg/dL, with no effect on HDL or triglycerides in either. NCCIH describes the reduction as small. The effect is real across several pooled analyses but modest, and no trial tracked heart attacks or strokes.^1,2,5
Blood pressure	Limited	A meta-analysis of 13 trials found systolic pressure fell by 2.08 mmHg and diastolic by 1.71 mmHg, with larger drops in people whose systolic pressure started at 130 mmHg or above. The Cochrane review of tea for cardiovascular prevention found bigger drops for green tea but said the results were not stable to sensitivity analysis and rested on few trials. Rated 2 because the effect is small and the pooled result is fragile.^3,4
Weight loss	Limited	The Cochrane review of trials of at least 12 weeks found no meaningful loss outside Japan (mean difference −0.04 kg, 95% CI −0.5 to 0.4, six studies, 532 people). Japanese trials ranged from −0.2 to −3.5 kg and could not be pooled. The authors concluded any loss is small, not statistically significant and unlikely to be clinically important, and that green tea did not help maintain weight after weight loss. NCCIH says the effect is modest at most. A null Cochrane review caps this use at 2.^6,5

Use

Evidence

What the research shows

Cholesterol (total and LDL)Compare remedies for heart health →

Moderate

Two meta-analyses of randomised trials found green tea catechins or green tea lower total cholesterol by about 5 to 7 mg/dL and LDL cholesterol by about 2 to 5 mg/dL, with no effect on HDL or triglycerides in either. NCCIH describes the reduction as small. The effect is real across several pooled analyses but modest, and no trial tracked heart attacks or strokes.^1,2,5

Blood pressure

Limited

A meta-analysis of 13 trials found systolic pressure fell by 2.08 mmHg and diastolic by 1.71 mmHg, with larger drops in people whose systolic pressure started at 130 mmHg or above. The Cochrane review of tea for cardiovascular prevention found bigger drops for green tea but said the results were not stable to sensitivity analysis and rested on few trials. Rated 2 because the effect is small and the pooled result is fragile.^3,4

Weight loss

Limited

The Cochrane review of trials of at least 12 weeks found no meaningful loss outside Japan (mean difference −0.04 kg, 95% CI −0.5 to 0.4, six studies, 532 people). Japanese trials ranged from −0.2 to −3.5 kg and could not be pooled.

The authors concluded any loss is small, not statistically significant and unlikely to be clinically important, and that green tea did not help maintain weight after weight loss. NCCIH says the effect is modest at most. A null Cochrane review caps this use at 2.^6,5

How much

Ranges below are what studies used and what supplements commonly contain. They are not a recommendation for you. Start at the low end.

Studied range (cholesterol)

145–3,000 mg catechins a day²

The range across 20 trials lasting 3 to 24 weeks in one meta-analysis. Products differ in catechin and caffeine content, so the label figure for EGCG matters more than the milligrams of extract.

Typical tea drinking

90–300 mg EGCG a day⁷

EFSA's estimate of mean EGCG intake from green tea infusions in the EU. High-level tea drinkers reach up to about 866 mg a day.

Liver warning level

800 mg EGCG a day or more⁷

EFSA found trials at this dose as a supplement raised serum transaminases compared with control. Food supplements in the EU provide 5 to 1,000 mg EGCG a day. France recommends not exceeding 300 mg EGCG a day and taking supplements with a meal.

Timing · No source we read gives a best time of day. Green tea contains caffeine, so an extract taken late may affect sleep, though we did not find a source quantifying this.With food? · Take extracts with a meal. EFSA and the US Pharmacopeia review both note that concentrated extract taken on an empty stomach or as a single bolus gives higher EGCG blood levels, and the USP linked fasting use to a greater chance of adverse effects.How long to trial · Cholesterol trials ran 3 to 24 weeks, so a lipid test after about 4 weeks is the most sensible check. Stop and seek medical advice if you notice yellowing of the skin or eyes, dark urine, stomach pain or unusual tiredness.

How people take it

Capsule or tablet (concentrated extract)Check the EGCG figure on the labelThe form linked to liver injury reports and to the trials that raised liver enzymes. NCCIH says injury has been reported primarily with extracts in tablet or capsule form.

Brewed green teaAbout 90–300 mg EGCG a day at typical intakesEFSA considers traditionally prepared green tea generally safe at usual European intakes, though rare liver injury has been reported after infusions too. Most cholesterol trials used extract rather than the drink.

Safety

Who should avoid

Liver disease or a history of liver injury — rare severe cases, mainly from extracts
Pregnancy and breastfeeding — France advises against supplements; ask a clinician
Children and adolescents — French guidance advises against supplements
Iron deficiency — EFSA's proposed label wording advises asking a professional first
Caffeine sensitivity — green tea and its extracts contain caffeine
On an empty stomach — higher blood levels of EGCG, more risk of harm

Known interactions

CautionBlood pressure medication — At high doses green tea has been shown to lower blood levels of nadolol, a beta-blocker for high blood pressure and heart problems.

CautionStatins (cholesterol medication) — NCCIH reports green tea extract can lower blood levels of atorvastatin, which may make it less effective.

Questions people ask

Is green tea extract the same as drinking green tea?

No. A cup of green tea delivers modest amounts of EGCG, and NCCIH reports no safety concerns for the drink in adults. Supplements can deliver several times that in one dose, and the liver injury reports involve mainly tablets and capsules.

Does green tea extract help you lose weight?

Not by a meaningful amount. The Cochrane review found weight change of −0.04 kg outside Japan and concluded any loss is too small to matter clinically. Effects in Japanese trials were larger but varied widely and could not be pooled.

Can green tea extract damage your liver?

Rarely, but yes. EFSA reviewed the evidence and concluded doses of 800 mg EGCG a day or more raised liver enzymes in trials, and a US registry study attributed 40 cases of serious liver injury to green tea products. Most had a gene variant called HLA-B*35:01, which suggests the reaction is immune-mediated and hard to predict.

Does green tea lower cholesterol and blood pressure?

Slightly. Pooled trials show LDL falling by roughly 2 to 5 mg/dL and systolic blood pressure by about 2 mmHg. These are small changes and no trial has shown fewer heart attacks or strokes.

Sources (8)

Reader notes

Experiences and questions from readers, read by an editor before they appear. They are personal accounts, not evidence, and are not medical advice.

Last reviewed 10 October 2026 · Next review April 2027 · How we rate evidence

Green Tea Extract

At a glance

What it's used for

How much

How people take it

Safety

Who should avoid

Known interactions

Questions people ask

Is green tea extract the same as drinking green tea?

Does green tea extract help you lose weight?

Can green tea extract damage your liver?

Does green tea lower cholesterol and blood pressure?

Sources (8)

Reader notes

Used it? Share how it went, or ask a question.