EGCG: Benefits and Safety
A Plant Compound Found in Green Tea
Medically reviewed by Allison Herries, RDN
Epigallocatechin gallate (EGCG) is a type of plant compound called a catechin. Catechins are part of a larger group of plant compounds (polyphenols) associated with health benefits.
EGCG has the following properties:
It's the most abundant polyphenol in green tea.
It contributes to tea's benefits.
Acts as an antioxidant to protect against cell damage caused by unstable molecules (free radicals).
It has anti-inflammatory properties that may also minimize cell damage and stress.
Due to its anti-inflammatory properties, EGCG has been studied for its potential benefits for the following:
Cognitive health
Heart health
Cancer protection
Still, more research is needed.
This article discusses the potential benefits of EGCG. It also covers dosage and safety concerns.
EGCG Supplement Facts
Active Ingredient(s): Polyphenol, flavanol
Alternate Name(s): (-)-Epigallocatechin gallate, EGCG, epigallocatechin 3-gallate, tea catechin, epigallocatechin 3-gallate, teavigo, catechin derivative, epigallocatechol, 3-gallate, EGCG cpd
Legal Status: Over-the-counter dietary supplement, generally regarded as safe by the Food and Drug Administration (FDA) and European Food Safety Authority (EFSA)
Suggested Dose: Recommended not to exceed 338 milligrams of EGCG daily through supplements
Safety Considerations: Individuals with liver disease; possible interactions with medications
Nutrition Sources of EGCG
Green tea is the most potent source of EGCG. The EGCG content of tea varies depending on the water temperature and steeping time. Likewise, harvesting practices can affect the nutrient content of tea leaves.
Other sources of EGCG include the following:
Matcha tea is a highly potent source of EGCG. Unlike green tea, matcha is not an infusion. Matcha contains a higher EGCG content than green tea due to its greater amount of compounds.
Tatiana Lavrova / Getty Images
Female hand pouring tea into transparent cup.Uses of EGCG
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Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian (RD) or registered dietitian nutritionist (RDN), a pharmacist, or a healthcare provider. No supplement is intended to treat, cure, or prevent disease.
The potential health benefits of EGCG are numerous and extend to brain and heart health, cancer prevention, and multiple sclerosis. Here's the scoop on the research.
Cognition
A systematic review suggested drinking at least 100 milliliters (mL) (about 3 ounces) of green tea daily boosted cognition and brain function and may reduce the risk of dementia. Green tea also enhanced memory and attention span.
The cognitive benefits of green tea are well established. However, it is unclear whether EGCG or other compounds found in green tea are responsible for these positive health effects.
Some studies of human brain cells (in vitro research, performed in a lab) suggested EGCG crossed the blood-brain barrier, a layer of cells that protects the brain from harmful substances. This may contribute to EGCG’s calming and stress-reducing benefits.
Mood
Regularly consuming green tea improves memory and mood and protects against depressive symptoms.
Research suggests that 300 milligrams (mg) of EGCG may increase calmness and reduce stress. However, other research notes improved overall mood only with higher dosages (800 mg) of EGCG, and achieving 300 mg EGCG through green tea alone is difficult.
One cup (8 ounces) of brewed green tea has 187 mg of EGCG.
Reaching 800 mg of EGCG would require drinking an amount of green tea that would exceed caffeine recommendations of 400 mg daily. This is not recommended.
Blood Pressure
Adding green tea to your routine may keep your blood pressure in a healthy range. Research shows that consuming any amount of green tea daily lowers blood pressure compared to not drinking green tea.
Catechins in green tea, like EGCG, improve blood pressure by increasing nitric oxide production. Nitric oxide is a chemical that enlarges blood vessels, causing blood pressure to decrease.
One randomized controlled trial observed a decrease in blood pressure after eight weeks with 150 mg EGCG taken twice daily.
Despite the beneficial effects of green tea on blood pressure, limited research exists on the specific influence of EGCG.
Cancer Prevention
Catechins in green tea, such as EGCG, may prevent cells from dividing and spreading.
Among randomized controlled trials, dosages of EGCG vary and are often higher than typically found in green tea. You would need to drink eight glasses of green tea to achieve the same amount of EGCG found in a supplement.
Some research suggests a link between drinking green tea and a reduced risk of cancer. However, much of the evidence is inconsistent. Again, it is unclear if EGCG supplements will yield the same benefits as green tea.
The National Cancer Institute believes insufficient evidence exists to support or reject EGCG for cancer prevention decisively.
Multiple Sclerosis
Multiple sclerosis (MS) is a chronic condition in which the body attacks the central nervous system, impacting communication between neurons and the brain. Some people with MS may experience the following symptoms:
Pain
Poor coordination
Animal research found a neuroprotective (brain protecting) and anti-inflammatory effect of EGCG. However, human studies have not observed similar results.
One small study of people with progressive MS observed no difference in the loss of brain cells (brain atrophy) between participants taking up to 1,200 mg EGCG daily and those given a placebo.
Cholesterol
Research suggests EGCG may reduce low-density lipoprotein (LDL) cholesterol. Elevated cholesterol, particularly LDL, is a significant risk factor for cardiovascular disease (CVD).
Consuming 2 to 8 cups of green tea daily lowers LDL and total cholesterol levels.
Evidence conflicts on the benefits of EGCG supplements for triglyceride levels. One randomized controlled trial observed a 30 milligram/deciliter (mg/dL) decrease in triglyceride levels with 300 mg EGCG daily. But other research shows increased triglyceride levels with green tea catechin or EGCG supplements.
While some research demonstrates the cholesterol-lowering ability of EGCG supplements, no conclusive evidence exists to support a specific dosage.
Energy Expenditure
EGCG may increase the amount of energy your body uses for normal functioning (energy expenditure).
One meta-analysis found that 300 mg EGCG daily could promote greater energy metabolism.
Another study found that consuming 100 to 460 mg of EGCG with 80 to 300 mg of caffeine daily for at least 12 weeks supported weight loss and encouraged greater changes to body composition.
However, whether the same effects can be achieved with EGCG supplementation alone is unknown.
Dosage
There is no specific dose recommendation to reap the benefits of EGCG.
The FDA classifies EGCG and green tea catechins as generally recognized as safe (GRAS) but does not provide specific dosage recommendations. Moreover, dosages and supplement forms used in studies vary.
A 1-cup (8 ounces or 240 mL) serving of green tea provides roughly 187 mg of EGCG. However, this amount can vary, depending on the type of tea leaf and processing and storing methods.
Matcha tea is more concentrated than green tea. Some research indicates matcha may contain 137 times the amount of EGCG as green tea.
Concentrated capsules or tablets of green tea extract or catechins contain higher amounts of EGCG. Depending on the supplement, dosages can range from 25 to 750 mg of EGCG. Green tea extract added to drink products provides an average of 200 mg EGCG per serving.
Still, some research suggests that 1,000 to 1,600 mg daily for three months can be safe. Other recommendations include 5 mg pure EGCG per kilogram (kg) of body weight (mg/kg) daily.
Safety of EGCG
The National Center for Complementary and Integrative Health (NCCIH) at the National Institute of Health (NIH) notes that it is safe to consume up to 8 cups of green tea daily (providing nearly 1,500 mg EGCG).
It is not recommended to ingest more than 338 mg of concentrated EGCG daily in solid supplement form. However, it can be easy to exceed this amount with capsule or tablet supplements.
Side Effects
Potential side effects of green tea extract pills include the following:
Liver problems may occur with green tea extracts in pill form. People with liver disease should be more cautious, as higher doses of concentrated EGCG can contribute to liver problems.
Consult with a healthcare provider immediately if you are taking a green tea extract pill and experience these symptoms, as it may be a sign of liver trouble.
Interactions
EGCG may interact with certain medications. These medications include the following:
Nadolol: Nadolol is a beta-blocker that treats high blood pressure and heart problems. Drinking significant amounts of green tea or high doses of EGCG may reduce the effectiveness of nadolol.
Lipitor (atorvastatin): Lipitor lowers LDL cholesterol and triglycerides in circulation. EGCG supplements may reduce the absorption and effectiveness of Lipitor.
Consult your healthcare provider before starting a supplement, as other interactions are possible.
Precautions
The following precautions should be noted for use of EGCG and products containing green tea (and thus caffeine):
Allergy: Avoid EGCG and green tea if you're allergic to them or their components (parts). Seek immediate medical attention if you have a severe allergic reaction (itching, hives, shortness of breath).
Pregnancy: EGCG in green tea can be safely consumed during pregnancy. Limiting green tea to less than 6 cups daily is recommended due to the caffeine content. Six cups of green tea equals about 300 mg of caffeine, the upper limit recommended during pregnancy. However, EGCG may benefit women diagnosed with gestational diabetes (diabetes that occurs in pregnancy) during the third trimester. One small clinical trial found that supplementing with 500 mg EGCG daily improved maternal treatment outcomes and reduced the risk of neonatal complications due to gestational diabetes. Try to limit caffeine when pregnant.
Breastfeeding: Like pregnancy, EGCG consumed via green tea is safe up to six cups daily. Caffeine is passed through breast milk. Limiting caffeine intake to less than 300 mg daily is recommended.
Children: One study found EGCG at 10 mg/kg was safe in children with Down syndrome. However, there is no established safe limit for caffeine intake among children.
Liver conditions: People with liver disease should consult their healthcare provider before starting a supplement with green tea extract or EGCG.
Insomnia: Consider limiting or avoiding caffeine if you have sleep issues like insomnia.
Anxiety: Consider limiting or avoiding caffeine if you have anxiety.
GERD or ulcers: Consider limiting or avoiding caffeine if you have gastroesophageal reflux disease (GERD) or ulcers.
High blood pressure: Consider limiting or avoiding caffeine if you have high blood pressure (hypertension).
Heart rate issues: Consider limiting or avoiding caffeine if you have issues with the rate or rhythm of your heartbeat (arrhythmia).
Children and teenagers: Pediatricians advise against the use of caffeine for children under 12. They also suggest limiting caffeine to 100 mg (about two 12-ounce cans of soda) or less daily for those 12 to 18.
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In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says.
When choosing a supplement, look for products tested by third parties, such as U.S. Pharmacopeia (USP) or ConsumerLab.com, and consult a healthcare provider, an RD or RDN, or a pharmacist.
Summary
EGCG may improve mood, cognition, cholesterol, and blood pressure. Although the potential benefits of EGCG are plentiful, questions remain about the effectiveness of EGCG-specific supplements.
Regularly drinking green tea provides EGCG and other nutrients beneficial to health without exceeding recommended EGCG dosages. Despite the advantages of green tea, it is still important to be mindful of the caffeine content.
Frequently Asked Questions
What is EGCG?
EGCG is a plant compound (polyphenol) found in green tea leaves. EGCG is associated with numerous health benefits.
Is EGCG safe?
Capsule or tablet supplements of EGCG up to doses of 338 mg daily appear safe for most individuals. People with liver disease or a history of liver issues should consult their healthcare provider before taking EGCG supplements.
Do EGCG supplements have caffeine?
Some EGCG supplements contain caffeine, while others do not. Read the supplement label carefully.
Read the original article on Verywell Health.
