Ever wonder why drinking green tea and other teas has been linked to longevity— not to mention cognitive health, protection against cardiovascular disease and much more? One reason is because of EGCG, a type of polyphenol antioxidant found in a variety of tea leaves.
While you can consume this catechin in supplement form, the best way to obtain it is by drinking several cups of high-quality, brewed tea each day. This habit has been shown in studies to support a healthy metabolism, help regulate blood pressure and protect the brain from age-related damage.
What Is EGCG?
EGCG, which stands for epigallocatechin gallate, is a beneficial plant compound called a polyphenol (which is a catechin, a type of flavonoid). It’s the most abundant catechin found in black and green tea leaves, although tea leaves contain other catechins too, such as epicatechin, gallocatechin and gallate derivatives.
Is green tea extract the same as EGCG? Green tea extract is made from dried green tea leaves, so it does contain EGCG, along with caffeine and other antioxidants. According to Examine.con, most green tea extract supplements are roughly 50 percent EGCG.
To increase your intake of this compound, the top EGCG foods and beverages to include in your diet are:
- Green tea (which has slightly higher amounts of catechins than black tea)
- Black tea
- White tea
- Oolong tea
- In smaller amounts, berries, including cranberries, strawberries, blackberries
- Other fruits like kiwis, cherries, pears, peaches, apples
- Some nuts, such as pistachios, pecans and hazelnuts
Did you know that green tea and black tea both come from the same plant? The Camellia sinensis evergreen shrub, which is native to China, India and other countries in Asia, produces nutrient-rich leaves that are harvested, steamed, dried or heated to make tea.
Black tea leaves are slightly more processed than green tea leaves, which lowers the flavonoid content and EGCG levels slightly.
Which green tea has the most EGCG?
The concentration of bioactive compounds, including polyphenols, in green tea can vary widely depending on preparation methods. Generally speaking, the type of green tea with the highest EGCG level is high-quality, ideally organic, brewed green tea.
You can help increase the EGCG concentration of your tea by steeping it in boiling water (not just hot water) and letting it sit for a full 10 minutes before removing the leaves. This method results in a stronger tea with a somewhat bitter taste, although the taste can be improved by adding some raw honey or fresh lemon juice.
You’ll also find high levels of EGCG in matcha green tea, a high-grade, finely ground, concentrated green tea that has been consumed in Japan for hundreds of years.
When you drink tea while eating a meal, some of the antioxidants may bind to minerals in the food you’re eating, making them a bit less bioavailable. If you want to maximize the amount of catechins you actually absorb, then drink tea alone and between meals.
If you’re looking to benefit from drinking more tea you’ll also want to avoid sweetened, bottled teas and premixed green teas, which are often lower in antioxidants and tend to be high in sugar.
Does EGCG contain caffeine?
EGCG is not the same thing as caffeine — however both are naturally found in both black and green teas.
The amount of caffeine in tea ranges from about 20 to 45 milligrams per eight-ounce cup, with black tea having a bit more than green tea. Both have a lot less caffeine than coffee, about half as much or even less depending on the kind of tea.
What is EGCG good for exactly? Based on what we know from available research, EGCG has certain anti-aging effects and can act like a natural therapeutic agent to aid prevention of some diseases.
This catechin has been shown to have these protective effects:
- Acts as an antioxidant and free radical scavenger
- Fights inflammation/inflammatory diseases by suppressing activity of pro-inflammatory chemicals
- Blocks neurodegeneration
- Acts as an anti-carcinogenic (protects against cancer)
- Has metal-chelating abilities
- Supports metabolic activities that may prevent weight gain and metabolic syndrome
- May help reduce development of cancer, diabetes, heart disease and neurodegenerative disorders
Here’s a bit more about some of the most well-known ECGC benefits and uses:
1. Fights Oxidative Stress/Inflammation
Studies investigating EGCG have found that it suppress accumulation of reactive oxygen species, alters signaling pathways in a way that prevents excessive inflammatory responses, lowers nitric oxide levels and reduces oxidative stress.
There’s also evidence suggesting that this polyphenol directly interacts with proteins and phospholipids and regulates signal transduction pathways, transcription factors, DNA methylation, mitochondrial function and autophagy (how the body cleans out damaged/dead cells).
All of this translates to enhanced protection against a wide range of health problems, especially those related to inflammation and aging.
2. Supports Heart Health
Catechins in tea leaves are thought to be responsible for many of their beneficial health effects linked to the heart and blood vessels.
According to Harvard Health Publishing, flavonoids help quell inflammation, and that in turn may reduce plaque buildup inside arteries, improve vascular reactivity, improve blood pressure and help lower LDL cholesterol levels.
There’s also evidence that regular tea drinkers may have a reduced risk of experiencing a heart attack or stroke.
3. Helps Protect the Brain
Researchers believe that EGCG has neuroprotective benefits due to its antioxidant effects and ability to invoke a range of cellular mechanisms in the brain. Consumption has been linked to increased protection against neurodegenerative diseases, such as Alzheimer’s disease, dementia and Parkinson’s disease.
Some studies have found that catechins can help reverse neural damage and prevent further neural death, decreasing declines in cognitive function as people age.
A number of large studies have found that adults who consume two to three cups of green tea daily for at least several years experience reduced prevalence of cognitive impairment, such a 30 percent to 40 percent lower risk of developing Parkinson’s.
In addition to suppressing cognitive dysfunction, EGCG may help increase learning ability by reducing oxidative damage in the brain.
4. Supports a Healthy Metabolism/Weight Loss
While not a quick fix for weight loss, there’s some evidence demonstrating that this compound can protect against metabolic syndrome and promote fat loss in several ways— such as by decreasing inflammation, suppressing your appetite and increasing energy expenditure. EGCG may also work in part by boosting thermogenesis (the body producing heat by using energy), although not every study has found evidence that these effects are substantial.
Consumption of two or more cups daily has been linked to a healthier body composition in certain studies.
For even stronger effects, EGCG and caffeine can be consumed together (such as from tea or some extracts and supplements). One study found that taking EGCG supplements along with caffeine for several months helped support fat loss among overweight adults.
One cup (eight ounces or 250 milliliters) of brewed green tea naturally contains about 50–100 milligrams of EGCG (and 30 to 40 milligrams of caffeine).
In addition to being found naturally in tea, EGCG supplements are also available over-the-counter.
What’s the best EGCG supplement to take?
Unfortunately, many supplements are not strictly regulated, making it difficult to ensure you get a pure product. Therefore the safest way to consume ECGC seems to be from real food/beverage sources, especially green and black tea.
Drinking one to four cups daily is thought to be healthy for most adults and poses little risk, unless someone is very sensitive to caffeine or oxalates found in tea (for example, because he or she has a kidney issue). Consuming two to three cups per day of high-quality brewed green tea (not bottled, sweetened green tea) is a common recommendation by health experts if you’re looking to benefit from catechins.
If you do decide to take EGCG supplements, how much should you take? There isn’t a standard recommendation, however one meta-analysis found that dosages between 150 and 2,500 milligrams of catechins daily from green tea or green tea extract was capable of helping improve patients’ cholesterol profiles.
Most experts recommend taking up to 400 milligrams in supplement form at first and not more than 800 milligrams before knowing how you react (and ideally with help from a health care provider).
Because there is a big range in terms of dosage recommendations, to narrow down how much you should consume, consider starting with a low dose between 150 and 400 milligrams daily and increasing slowly if needed. One study found beneficial effects on body weight when adults consumed up to 460 mg/day — therefore high doses might not be needed in most instances.
Risks and Side Effects
Because there’s limited evidence about the effectiveness and safety of EGCG supplements, it’s important to both follow dosage recommendations and to buy a high-quality product. Consuming high doses in supplement form has been linked to potential liver damage, so be careful to avoid taking too much.
To ensure you take an appropriate amount, look for a supplement that lists the amount of catechins and EGCG per serving. To limit risks for potential side effects, stick to doses under 800 mg/day.
If you’re very sensitive to caffeine or oxalates, minimize your tea consumption and avoid supplements that contain caffeine and other stimulants.
Stop using EGCG supplements if you notice any of the following symptoms:
- low blood sugar
EGCG supplements and green tea extract also shouldn’t be taken by pregnant women or patients suffering from renal failure, liver disease or certain heart conditions. If you take medications daily to control your cholesterol or blood pressure levels, talk to your doctor before supplementing.
- EGCG stands for epigallocatechin gallate. It’s a type of plant compound called a catechin that is found most abundantly in green and black tea leaves.
- EGCG benefits and uses include fighting inflammation and oxidative stress, supporting heart health and metabolic function, supporting weight loss, and protecting the brain against degeneration.
- To reap the benefits of this compound, most adults can safely consume two to four cups of brewed green tea daily.
- Be cautious when using EGCG supplements, starting with a low dose under 400 mg/day and monitoring your reaction.