Green Tea Extract: EGCG & Safety
A cup of green tea and a green tea capsule are not the same thing. Extracts concentrate catechins such as EGCG, and the EU now caps how much EGCG a supplement may provide each day. Learn how to read percentages, count caffeine and spot liver warning signs. No health claim for green tea extract is authorised in the EU.
What green tea extract is
Green tea comes from the leaves of Camellia sinensis, the same plant used for black tea, but the leaves are heated soon after picking so they do not oxidise. The leaves contain catechins, a family of polyphenols, of which EGCG (epigallocatechin gallate) is the most abundant. They also contain caffeine and the amino acid L-theanine.
Green tea extract concentrates these compounds into capsules or powders. Studies have looked at green tea and its catechins in many areas, including body weight, with mixed and generally modest results. No health claim for green tea extract is authorised in the EU, and the EU has tightened the rules on EGCG in supplements, so this guide focuses on amounts and safety. You can find green tea extract in our vitamins and supplements range.
Forms you'll see on labels
| Form | What to know |
|---|---|
| Standardised extract (% polyphenols) | States total polyphenols, for example 50% or 98%. EGCG is only part of that figure. |
| Standardised extract (% EGCG) | States EGCG directly, for example 45%. This is the figure that matters for the EU limit. |
| Decaffeinated extract | Most caffeine removed. Useful if you are sensitive to caffeine, but catechin content is unchanged. |
| Matcha powder | Whole ground tea leaves. Contains caffeine and catechins at lower concentrations than extracts. |
| Multi-ingredient weight or energy blends | Often combined with caffeine, coffee extract and other stimulants. Amounts of green tea may be pooled with other extracts. |
| Iced tea sachets and drinks | Beverages with small amounts of tea. Not comparable to extract capsules. |
Examples from our shelves for some of the forms in the table above.
How much: the EU EGCG limit and caffeine
- NRV: none. Catechins are not nutrients.
- EU limit: since December 2022, EU law (Regulation 2022/2340) requires green tea extract supplements to provide less than 800 mg of EGCG per daily portion. EFSA had found that intakes of 800 mg EGCG a day or more from supplements were linked to raised liver enzymes.
- Required EU warnings: products must state that they should not be used by pregnant or breastfeeding women or children under 18, should not be taken on an empty stomach, and should not be combined with other green tea products on the same day.
- Caffeine: a cup of brewed green tea usually provides roughly 30 to 50 mg of caffeine. Extracts vary widely, so check the label if it is not decaffeinated.
- Food sources: brewed green tea. Drinking green tea as a beverage has not been linked to the liver problems seen with concentrated extracts.
Who should check with a doctor or pharmacist first
- Liver: uncommon but serious liver injury has been reported with green tea extract tablets and capsules, usually within 1 to 6 months. Stop and see a doctor if you notice tiredness, nausea, dark urine or yellowing of the skin or eyes. People with liver conditions should not use extracts without medical advice.
- Pregnancy and breastfeeding: EU rules say extracts should not be used at these times. Ask your doctor about caffeine from tea.
- Children and under-18s: EU labelling says not for under-18s. Check the age on the pack.
- Medicines: green tea can lower blood levels of nadolol (a beta-blocker), and green tea extract can lower levels of atorvastatin. Ask a pharmacist about any regular medicine.
- Iron: tea catechins can reduce how much iron you take up from plant foods. If you have been told your iron is low, take tea and extracts away from meals.
- Caffeine sensitivity, heart rhythm concerns or anxiety.
How to read the label
- Find EGCG per serving: multiply the extract weight by the EGCG percentage. 400 mg of a 45% EGCG extract provides 180 mg EGCG.
- Polyphenols are not EGCG: a 98% polyphenol figure includes several catechins, so EGCG will be lower.
- Add up servings: two capsules twice a day means four times the per-capsule amount. Stay below 800 mg EGCG from all products combined.
- Caffeine: look for a stated caffeine figure or the word decaffeinated, and count coffee, energy drinks and pre-workouts too.
- Bundles: check whether more than one item in a bundle or routine contains green tea.
Bahrain and GCC notes
Take green tea extract with a meal, not on an empty stomach, which matters if you are fasting in Ramadan: use it with iftar or suhoor and avoid it late at night if caffeine affects your sleep. Gulf diets often include plenty of karak and Arabic coffee, so add those to your caffeine total. Store capsules in a cool, dry place away from direct sunlight.
Reading a real label
BP Green Tea 400 mg, 60 Capsules| On the label | What it means |
|---|---|
| 400 mg green tea extract | Per capsule |
| 160 mg caffeine | About the same as 2 cups of brewed coffee; count it toward 400 mg a day |
| No EGCG % listed | Standardised extracts state polyphenols or EGCG |
| Take with a meal | As the label directs |
No health claim is authorised for this ingredient in the EU. We share facts only.
Products with Green Tea Extract
Always read the label and check the amount per serving.
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BPBP Antioxidant Wellness Bundle
BPBP Green Tea 400 mg, 60 CapsulesFrequently asked questions
How do I work out the EGCG in my capsule?
Multiply the extract weight by the EGCG percentage on the label. If only total polyphenols are given, the EGCG content will be lower than that figure.
Is drinking green tea the same as taking an extract?
No. Extracts are far more concentrated, and the liver concerns relate mainly to extract tablets and capsules rather than brewed tea.
Does green tea extract contain caffeine?
Usually yes, unless it is labelled decaffeinated. Check the caffeine figure and count other sources such as coffee and energy drinks.
Should I take green tea extract on an empty stomach?
No. EU labelling rules state that green tea extract supplements should not be taken on an empty stomach.
Is there an authorised EU health claim for green tea extract?
No. No health claim for green tea extract is authorised in the EU.
