Everything you need to know about green tea extract supplements

Green tea extract contains potent antioxidants naturally found in green tea that are associated with numerous health benefits. Here’s everything you need to know about green tea extract supplements and whether you want to consider adding them to your routine.

For centuries, people have hailed the health benefits of green tea —and for good reason. Green tea contains potent antioxidant compounds called polyphenols that have been shown to support skin, brain, and heart health, enhance weight loss, and possibly even protect against cancer [1, 2, 3]. But are there any benefits to taking green tea extract?
In this guide, we will take a closer look at what green tea extract is, any science-backed benefits, what you should look for in a green tea supplement, and how much you should take. So, pour yourself a cup of green tea and dive in!
green tea supplements

What is green tea extract?

Green tea extract is extracted from the leaves of the Camellia sinensis plant and is a highly concentrated form of green tea. It contains potent antioxidants–such as flavonoids and polyphenols like epigallocatechin gallate (EGCG)–that protect against cell damage and offer a variety of health benefits [1,4, 5].

Green tea extract benefits

Studies have shown that consuming green tea and green tea extract could have several positive effects on your health. From supporting weight loss to boosting energy, skin, and heart health and even protecting against cancer, here are the science-backed benefits of taking green tea extract. 

Green tea heart benefits

Drinking green tea is associated with a reduced risk of heart disease and a lower risk of heart disease-related death, particularly in males [1]. Green tea extract may also provide similar benefits and support heart health by helping to reduce blood pressure and improve cholesterol. 
These benefits are associated with green tea’s anti-inflammatory compounds like EGCG, which have been shown to reduce inflammation and relax blood vessels, as well as lower levels of “bad” LDL cholesterol [6,7].
The optimal dose of green tea extract for cholesterol and blood pressure benefits is unknown, but one study in obese patients with hypertension found that taking 379 mg/day of green tea extract produced favorable improvements in both blood pressure and cholesterol numbers [8]. 

Improved alertness, attentiveness, and mood

When you need a little pick-me-up, consider green tea extract for energy. 
Green tea naturally contains caffeine, a stimulant that has been shown to boost alertness, energy levels, and reaction time, as well as improve mood and memory [9]. Research also shows that EGCG may reduce oxidative damage and inflammation and might help increase attentiveness while promoting calm and relaxation [10]. 
Before you take green tea extract, it’s good to know just how much caffeine you’re getting. Be sure to read our FAQ section for more information about green tea extract and caffeine and tips for safe consumption. 

Healthier skin and improved acne

Studies investigating the benefits of green tea extract show topical green tea extract may be beneficial for both acne and aging skin. 
If you suffer from acne, topical application of green tea solutions or EGCG has been shown to help reduce sebum production, blackheads, and inflammation associated with acne [2]. 
Studies have also proven that green tea extract improves skin moisture, reduces roughness, and neutralizes free radicals, making it very effective for treating and slowing the age-related deterioration of the skin [11].  
For skin benefits, topical application is more effective than the ingestion of green tea or green tea extract [2]. Concentrations between 1-6% ECGC and 2-3% green tea solutions have produced positive results related to acne, skin moisture, and smoothness [2, 11].

It may boost weight loss

If you’re looking to lose weight, many studies exploring green tea extract for weight loss have shown that green tea may be worth considering. 
Green tea supplements, particularly those with caffeine, are associated with modest but statistically significant reductions in BMI, body weight, and waist circumference [2, 12, 13]. 
One study in obese women found taking 857 mg/day of green tea extract with EGCG produced more significant weight loss and waist circumference reductions than a placebo [12]. As a bonus, the green tea group also saw a decrease in total cholesterol and LDL cholesterol levels without any notable side effects [12]. 
Some researchers attribute green tea’s weight loss benefits to lower ghrelin production (the body’s primary hunger hormone) and an increase in adiponectin. This hormone helps with insulin sensitivity, inflammation, and fatty acid breakdown [12, 14].
Despite some potential benefits on the scale, green tea extract is not a miracle weight loss pill. Evidence shows that by itself, green tea extract does not lead to reductions in key measurements like weight or waist circumference [13]. Therefore, to maximize its potential weight loss benefits, you will need to combine green tea extract with a healthy diet, plenty of physical activity, and healthy sleep and stress-management habits.

Anti-cancer benefits

Researchers are also exploring the potential benefit of green tea extract for cancer. Early clinical studies have shown that the polyphenols present in green tea may play an important preventative role in the following types of cancer [1, 15, 16]:
  • Endometrial cancer: Green tea has been  linked to a reduced risk of developing cancer of the lining of the uterus [1]. 
  • Breast cancer: Drinking green tea may reduce the risk of breast cancer by 15% [17].
  • Ovarian cancer: Regularly drinking green tea seems to reduce the risk of ovarian cancer [1].
  • Colorectal cancer: Some studies have shown that green tea drinkers have a 30–40% lower chance of developing colorectal cancer [18].
Researchers also believe that polyphenols may help kill cancerous cells and stop them from growing. For example, laboratory studies have found that green tea extracts prevent the growth of prostate cancer cells in test tubes. Still, more research is needed to explore whether these benefits can be replicated in a clinical setting and whether green tea extract has any treatment benefit [3].
While these results seem promising, much of the research has involved green tea drinkers, not supplements, and many other studies have produced conflicting results. More research is needed to explore green tea's potential anti-cancer benefits, specifically using green tea extract.
green tea powder

What to look for in green tea extract supplements

When it comes to choosing a green tea extract supplement, it’s important to know that not all supplements are created equal. For example, some green tea supplements contain only dry green tea leaves, while others contain isolated forms of one or more polyphenols, like EGCG.
Here are some things to consider when choosing a green tea supplement.
  • Know what you’re getting: Because supplements are not government-regulated, they should be evaluated for purity and quality by a reputable testing organization.
  • The form of green tea and potency: You’ll want to know whether your supplement  contains only dry green tea leaves or isolated forms of antioxidants. Supplements made with isolated antioxidants will be more potent and potentially provide more significant benefits. 
  • Whether it contains EGCG: You will find antioxidants listed as polyphenols, catechins, or EGCG on a green tea supplement label. Since EGCG is the most widely researched green tea antioxidant and is closely linked to its health benefits, you should look for a supplement that contains this polyphenol [2]. 
  • How much caffeine the supplement contains: Green tea extract supplements can contain vastly different amounts of caffeine, from zero to mega doses of 200 mg or more. Consuming too much caffeine can leave you feeling jittery, cause heart palpitations, and interfere with sleep, so it’s good to know how much your supplement contains.  
Product Supplements Image5 2x (1)

What is the best green tea extract?

If you’re not sure about which green tea extract supplement is right for you, there’s no need to worry. At Elo, we provide science-backed personalized smart supplements made just for you based on at-home blood testing, biomarkers, a questionnaire, and data from wearables. Depending on your goals, your personalized blend may contain green tea extract, along with a variety of other targeted supplements to help you feel your best. 
We also offer 1:1 dietitian support with our Elo Health coaches so you can stay accountable, reach your goals, and better understand your health. 

How to take green tea extract

Green tea extract supplements come in liquid, powder, and capsule form and are typically standardized to the amount of polyphenols or antioxidants they provide [1]. For topical applications, green tea extract can also be found in certain creams or skincare products. 
Green tea extract pills (capsules) are popular because they are convenient and don’t have as strong a taste as liquid and powder forms can. If you like the taste of green tea, you can dilute green tea extract liquid in a glass of water and blend green tea extract powder into smoothies. 

How much should you take?

While there are no official green tea extract dosing guidelines, studies have shown favorable effects with a green tea extract intake of 300-800 mg/day [2]. Intake of EGCG from supplements (which typically make up about 40-50% of the polyphenols in green tea extract) appears safe at 338 mg/day [2, 19]. 

Green tea extract side effects

While green tea supplements are generally well tolerated, consuming large doses of green tea extract can increase the risk of side effects due to the caffeine content [1]. The side effects of green tea extract are comparable to caffeine and include restlessness, jitters, heart palpitations, and difficulty sleeping, and it may also worsen anxiety [1]. 
Green tea extract also contains a chemical linked with liver injury when used in high doses [1]. In humans, the maximum tolerated dose is around 4.2 g/m2 once daily, or 1.0 g/m2 thrice daily. For someone who is 5 feet 10 inches tall and weighs 150 pounds, acute toxicity would occur at a daily dose of 7.9 g/day or 1.9g 3x/day [1]. 
If you suddenly stop using green tea extract, you may experience caffeine withdrawal symptoms, such as headaches, irritability, and nervousness. To help prevent withdrawal, lower your dose slowly. Withdrawal is more likely if you have used green tea extract for a long time or in high doses [20].

Green tea extract precautions

Consult your doctor or pharmacist before taking green tea extract if you have any of the following conditions [20]: 
  • Anemia (iron deficiency anemia)
  • Bleeding problems
  • Diabetes
  • Glaucoma
  • Heart problems such as irregular heartbeat or recent heart attack
  • Stomach or intestinal problems such as ulcers or reflux disease (GERD)
  • Liver problems
  • Mental/mood disorders (such as anxiety and panic attacks)
  • Low levels of calcium in the blood 
  • Bone problems such as osteoporosis
Here are some other things to keep in mind before adding green tea extract to your routine.

May inhibit iron absorption

Green tea catechins, primarily EGCG, have been shown to inhibit iron absorption. To avoid this, consider taking green tea supplements two hours before or after eating iron-rich foods like meat, poultry, shellfish, beans, tofu, and fortified breakfast cereals. You can also reduce this interaction and enhance iron absorption by pairing your plant-based iron-rich foods with vitamin C [2]. 

Might reduce blood levels

Green tea has been shown to reduce blood levels and the effectiveness of certain blood pressure and heart medicines at high doses. Consult your healthcare provider before taking high doses of green tea extract [20]. 

May not be appropriate for pregnancy

If you are pregnant, consult your doctors about the risks and benefits of green tea extract supplements before taking them. As previously mentioned, most green tea supplements contain caffeine, and it is recommended that women limit caffeine during pregnancy. This product may also decrease folic acid, and low levels of folic acid are associated with an increased risk of neural tube defects [20].
green tea steeping in a glass kettle

Frequently asked questions about green tea extract

Is green tea extract safe?

Research repeatedly shows green tea extract is safe when taken in doses up to 800 mg/day, possibly for up to two years [1, 2]. Individual studies have shown single doses from 1,200-1,600 mg EGCG can be tolerated; however, as dose size increases, so does the incidence of side effects [2]. 
Toxicity can occur from very high doses of green tea extract. In humans, the maximum tolerated dose is around 4.2g/m2 once daily, or 1.0g/m2 thrice daily. For example, for someone who is 5 feet 10 inches tall and weighs 150 pounds, acute toxicity would occur at a daily dose of 7.9 g/day or 1.9g 3x/day [1]. 

How long does green tea extract take to work? 

While you may experience benefits sooner, many studies have shown green tea extract benefits in as little as 8-12 weeks of supplementation [2]. 

Where does green tea extract come from?

Green tea extract comes from the leaves of the Camellia sinensis plant. For green tea, young leaves of the plant are harvested, withered, steamed, or pan-fried, then dried. This process preserves many beneficial compounds in green tea, which can then be extracted and consumed as a supplement.

Does green tea extract have caffeine? 

Green tea extract often has caffeine. The amount of caffeine in green tea extract can vary widely, from mild (2-50 mg caffeine) to mega-dose (>200 mg caffeine). 
If you’re new to green tea supplements or don’t regularly consume caffeine, it’s best to start with a supplement that contains a more modest amount of caffeine (30-50 mg) and adjust your intake accordingly. Up to 400 mg of caffeine daily appears safe for most healthy adults [21]. Taking green tea extract earlier in your day will also minimize the risk of its caffeine affecting your sleep.
If you prefer to avoid caffeine, decaffeinated green tea supplements contain little to no caffeine. 


Green tea extract is a highly concentrated form of green tea that contains potent antioxidants. Green tea has several health benefits, from supporting weight loss to boosting energy, skin, and heart health and even protecting against cancer. Moderate intake of green tea extract in the 300-800 mg/day range appears safe and effective, possibly for up to two years [1, 2]. To get the most out of your green tea supplements, choose one that has been quality tested and contains EGCG. At Elo, our expert dietitians can help you determine whether green tea extract supplements might benefit you.
Disclaimer: The text, images, videos, and other media on this page are provided for informational purposes only and are not intended to treat, diagnose, or replace personalized medical care.

Key takeaways

  • Green tea extract may have several health benefits, from boosting weight loss and energy levels to improving skin and heart health and protecting against cancer. 
  • Moderate intake of green tea extract in the 300-800 mg/day range appears safe and effective, possibly for up to two years.
  • Green tea supplements often contain caffeine. Know how much your green tea extract contains and how much you’re getting from other supplements, foods, and beverages. Up to 400 mg of caffeine daily appears safe for most healthy adults. 
  • Consuming too much green tea extract can interfere with certain medications and lead to toxicity and liver damage. Stick to the recommended dose to minimize your risk of side effects or adverse reactions.
  • Elo Health dietitians can help you determine whether green tea extract might be beneficial and recommend the dosage that’s best for you.


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