Green tea extract explained: what it is and side effects
Green tea comes from Camellia sinensis leaves that are steamed, pan fried and dried without fermentation. The NIH says extracts range from lightly processed leaves to concentrates of single compounds such as EGCG. Six of the products we reviewed list green tea extract, and one label prints its amount: 75 mg per serving.
- What it is
- Plant
- Amounts the NIH names
- 141 to 1,207 mg of green tea catechins per dose in studies
- In the products we reviewed
- 6, 1 print the amount
What green tea extract is
- Green tea is made from the leaves of the Camellia sinensis plant, which are steamed, pan fried and dried but not fermented.1
- Green, black and oolong teas all come from the same plant, Camellia sinensis, prepared in different ways.1
- The tea plant was first grown in China thousands of years ago.1
- The main active compounds in green tea are caffeine and catechins, mostly epigallocatechin gallate (EGCG).2
- A typical brewed cup of green tea has about 240 to 320 mg of catechins and 45 mg of caffeine.2
- Green tea extracts range from lightly processed tea leaves to concentrates of single compounds such as EGCG.2
How much green tea extract each product gives
NIH: 141 mg to 1,207 mg per dose
Amount not printed: the dashed line shows the most it can be, the whole blend
Before you take it
If you take medicines
Foods and drinks
- Food
- Liver problems are more likely when green tea extract is taken on an empty stomach, so the USP advises taking it with food.2
Side effects
- Green tea as a drink has no reported safety concerns for adults, but it does contain caffeine.1
Ask a doctor first
- Liver injury has been reported in some people who used green tea products, mostly green tea extract tablets or capsules, though it is uncommon.1
- Green tea can lower blood levels of some medicines, such as nadolol and atorvastatin, so people who take medicine should talk with a health care provider first.1
- Green tea is a source of caffeine, and caffeine during pregnancy should stay at moderate levels.1
These statements have not been evaluated by the FDA. A supplement is not a medicine.
The 6 products we reviewed that list green tea extract
| Product | Form and serving | Green tea extract per serving | Our score | Price a bottle | Buy |
|---|---|---|---|---|---|
 GlucoTonic#1 in blood sugar support | Liquid drops1 ml | Not printedIn a 200 mg proprietary blend | 9.9 | $49 | Check price |
 Insufend#2 in blood sugar support | Capsules1 capsule | Not printedIn a 525 mg proprietary blend | 9.6 | $49 | Check price |
 FitSpresso#2 in weight loss support | Capsules1 capsule | 75 mg | 9.5 | $39 | Check price |
 Sugar Defender#3 in blood sugar support | Liquid drops1 ml | Not printedIn a 200 mg proprietary blend | 9.5 | $49 | Check price |
 Glyco Harmony#5 in blood sugar support | Liquid drops1 ml | Not printedIn a 200 mg proprietary blend | 9.3 | $49 | Check price |
 SeroBurn#3 in weight loss support | Capsules2 capsules | Not printedIn a 843.5 mg proprietary blend | 9.3 | $49 | Check price |
Questions people ask
What is green tea extract?
Green tea extract ranges from lightly processed tea leaves to concentrates of single compounds such as epigallocatechin gallate (EGCG). The NIH names caffeine and catechins, mostly EGCG, as green tea's main active compounds.
How much caffeine does green tea have?
A typical brewed cup of green tea has about 45 mg of caffeine, according to the NIH. It also has about 240 to 320 mg of catechins.
What are the side effects of green tea extract?
Uncommon liver injury has been reported in some people who used green tea products, mostly extract tablets or capsules. Green tea as a drink has no reported safety concerns for adults, but it contains caffeine. If you are pregnant, ask a clinician before starting, since caffeine during pregnancy should stay at moderate levels.
When should I take green tea extract?
The USP advises taking green tea extract with food. Liver problems are more likely when the extract is taken on an empty stomach.
Which products we reviewed contain green tea extract?
Six products we reviewed list green tea extract: GlucoTonic, Insufend, FitSpresso, Sugar Defender, Glyco Harmony and SeroBurn. FitSpresso prints 75 mg per 1 capsule serving. The other five list it inside proprietary blends without printing a separate amount for green tea extract.
Also in these products
Sources
The products, amounts and prices come from each product's label and checkout, as its review shows them. AI drafts our pages from listed sources, figures are checked against them, and we have not tried the products.
- 1NIH National Center for Complementary and Integrative Health, Green Tea: Usefulness and Safetynccih.nih.gov/healthchecked
- 2NIH Office of Dietary Supplements, Dietary Supplements for Weight Loss, Fact Sheet for Health Professionalsods.od.nih.gov/factsheetschecked