EGCG

Best for

Lose weight

Large effect, needs confirmation 379–1970 mg/day 6–12 weeks 3 studies, n=250 #1 of 72 studied

32 papers
5 of 103 outcomes
3 positive
1 severe

EGCG shows a large effect on movement-related weight outcomes in adults with overweight or obesity, but confirmation is needed; fat-use benefits remain early signals.

Risk, worst reported severity

hepatotoxicity by usnic acid severe
digestive symptoms (bloating, constipation) mild

All 8 events and interactions

Outcome Effect Evidence Dose Time Rank

Worth watching 3 Interesting effects seen in early studies

Lose weight Large effect, needs confirmation

Weight loss means carrying less total body weight over time. 22581111 · 27054321 · 30400924

large

3 RCTs 3 papers · n=250

379–1970 mg

6–12 wk

#1 /72

Use more fat for energy Promising early signal

Fat burning means your body uses stored or circulating fat as a source of energy. 19952844 · 26184298 · 36695951 +1

moderate

2 RCTs 4 papers · n=130

250–1450 mg

0–0 wk

#9 /21

Lose belly fat Promising early signal

Belly fat is fat stored around the abdomen, including fat deep inside the belly. 22581111 · 30400924

moderate

2 RCTs 2 papers · n=46

379–856.8 mg

6–12 wk

#5 /40

Early research 2 Not enough research to say yet

A smaller body size Not enough research

Clothes can fit differently when body size changes. 30400924

small

1 RCT 1 papers · n=146

856.8 mg

6 wk

—

Lose body fat Not enough research

Body fat loss changes the proportion of your body that is fat tissue. 27054321

trivial

1 RCT 1 papers · n=58

1350–1970 mg

12 wk

#1 /41

Outcome	Effect	Evidence	Dose	Time	Rank
Worth watching 3
Lose weight Large effect, needs confirmation Weight loss means carrying less total body weight over time.	large	3 RCTs 3 papers · n=250	379–1970 mg	6–12 wk	#1 /72
Use more fat for energy Promising early signal Fat burning means your body uses stored or circulating fat as a source of energy.	moderate	2 RCTs 4 papers · n=130	250–1450 mg	0–0 wk	#9 /21
Lose belly fat Promising early signal Belly fat is fat stored around the abdomen, including fat deep inside the belly.	moderate	2 RCTs 2 papers · n=46	379–856.8 mg	6–12 wk	#5 /40
Early research 2
A smaller body size Not enough research Clothes can fit differently when body size changes.	small	1 RCT 1 papers · n=146	856.8 mg	6 wk	—
Lose body fat Not enough research Body fat loss changes the proportion of your body that is fat tissue.	trivial	1 RCT 1 papers · n=58	1350–1970 mg	12 wk	#1 /41

Effect tiers come from native-unit MCID where available, Cohen's d otherwise.

Protocol

Dose, timing & forms

How much

The early weight-management trials examined roughly 379 to 1,970 mg/day of EGCG or comparable catechin-rich green tea preparations. That is a very wide research range, and the largest weight-loss signal still needs confirmation, while broader reviews of green tea preparations show inconsistent average results. 1 2 Start conservatively rather than chasing the top end of the range, especially with concentrated extracts. ³

When and how long

Research tests EGCG as a daily routine, not as an occasional pre-workout boost, so consistency matters more than a precise clock time. 1 2 Take a concentrated extract with a meal rather than on an empty stomach, and avoid treating higher doses as better because supplement-level catechins raise liver-safety concerns. ³

Forms & standardisation

Choose a product that lists its actual EGCG amount or total green tea catechins, rather than one that simply says “green tea leaf.” Most human weight-management research used green tea extracts containing several catechins, and often caffeine, so evidence for those blends does not cleanly transfer to caffeine-free isolated EGCG. 1 2 Avoid products that hide a large proprietary extract dose without telling you its catechin content.

Safety events

hepatotoxicity by usnic acid severe

digestive symptoms (bloating, constipation) mild

gastrointestinal events (bloating, diarrhoea, nausea, abdominal pain, constipation) mild

headache mild

increased liver enzymes (ALT/AST elevations)

increased bleeding time

fatigue

heartburn

In context

What this is and how it works

Across 3 studies (n=250), EGCG reduced weight-related movement outcomes; quantitative effect and MCID were not provided.1
The review covered 32 papers and 103 outcomes, including four early fat-use studies involving 130 participants.
Findings primarily involve green tea extracts and overweight or obese adults, limiting certainty for isolated EGCG supplements.

EGCG, short for epigallocatechin gallate, is a plant compound called a catechin that naturally occurs in green tea. Brewed tea delivers a relatively gentle amount, while capsules and powdered extracts can pack a much more concentrated dose. Research often tests EGCG as part of a green tea extract, sometimes alongside caffeine, rather than as a completely isolated ingredient. 1 2

EGCG appears to slow one cleanup enzyme that clears norepinephrine, a chemical messenger that tells fat cells to release stored fuel. Think of it as keeping the “use stored fuel” signal on the screen a little longer, which helps explain the fat-oxidation shift seen in a small exercise study. 4 That shift does not automatically translate into lasting weight loss, and larger reviews find that body-weight results vary across studies. 1 2

Bottom line

EGCG is worth watching if you want a modest, evidence-aware addition to a weight-management routine and you already have the basics in place. The fat-use research is intriguing, but sustained weight loss remains unproven and results differ across products and people. Skip high-dose extracts if you have a history of liver problems or unexplained elevated liver enzymes. 1 2 ³

Frequently asked

Common questions

Does EGCG work for weight loss?

Early trials show an interesting weight-loss signal, but reviews of green tea preparations find inconsistent results and only modest average changes. Treat EGCG as an experiment alongside food and activity habits, not a shortcut. ¹ ²

Is EGCG the same as drinking green tea?

EGCG is a major catechin in green tea, but a concentrated extract can deliver far more than a cup of brewed tea. Many weight-management trials also used mixtures of catechins and caffeine, so their results do not prove that isolated EGCG works identically. ¹ ²

Can EGCG increase fat burning during exercise?

A small human study found that green tea extract increased fat oxidation during moderate exercise. That is a fuel-use change, not proof of meaningful long-term fat loss. ⁴

Is high-dose EGCG safe?

Concentrated green tea catechin supplements have been linked with elevated liver enzymes in some people. Stop use and seek medical advice for symptoms such as unusual tiredness, dark urine, or yellowing of the skin or eyes. ³

Sources

Generated August 27, 2026

EGCG

Dose, timing & forms

What this is and how it works

Common questions

More evidence for EGCG

From Monk's Bowl to Molecule: How EGCG Walked Out of Tea and Into Modern Medicine

Focus & memory: evidence map across 45 supplements

Metabolic health: evidence map across 82 supplements

What egcg actually does

Adverse events and drug interactions

Sources

More evidence for EGCG

NewFrom Monk's Bowl to Molecule: How EGCG Walked Out of Tea and Into Modern Medicine

NewFocus & memory: evidence map across 45 supplements

NewMetabolic health: evidence map across 82 supplements

From Monk's Bowl to Molecule: How EGCG Walked Out of Tea and Into Modern Medicine

Focus & memory: evidence map across 45 supplements

Metabolic health: evidence map across 82 supplements