Green tea is one of the most commonly consumed teas in the world.
Green tea extract is its concentrated form, with just one capsule containing the same amount of active ingredients as an average cup of green tea.
Like green tea, green tea extract is a great source of antioxidants. These have been credited with a range of health benefits, from promoting heart, liver and brain health to improving your skin and even reducing the risk of cancer ().
What’s more, many studies have looked at green tea extract’s ability to aid weight loss. In fact, many weight loss products list it as a key ingredient.
This article explores 10 science-based benefits of green tea extract.
The health benefits of green tea extract are mostly due to its high antioxidant content.
Antioxidants can help reduce oxidative stress by fighting cell damage caused by free radicals. This cell damage is associated with aging and several diseases ().
Polyphenol antioxidants called catechins comprise the majority of green tea extract’s antioxidant content. Among the catechins in green tea, epigallocatechin gallate (EGCG) is the most researched and thought to provide the most health benefits.
Studies have shown that green tea extract increases the antioxidant capacity of the body and protects against oxidative stress (, , ).
For example, one study had 35 obese people take 870 mg of green tea extract for eight weeks. Their blood antioxidant capacity increased from 1.2 to 2.5 μmol/L, on average ().
Green tea extract boosts antioxidant capacity, which may help prevent various health problems caused by oxidative stress.
Summary:Green tea extract is rich in antioxidants called catechins, which have been shown to increase antioxidant capacity and protect against oxidative stress.
Oxidative stress increases fat buildup in the blood, which promotes inflammation in the arteries and leads to high blood pressure (, ).
Fortunately, the antioxidants in green tea extract can decrease inflammation and help reduce blood pressure. They can also inhibit fat absorption in cells, helping reduce blood fat levels (, , , ).
One study had 56 obese people with high blood pressure take 379 mg of green tea extract daily for three months. They showed a significant decrease in blood pressure, compared to the placebo group ().
Additionally, they experienced significant reductions in blood fat levels, including lower triglycerides and total and LDL cholesterol ().
Another study in 33 healthy people found that taking 250 mg of green tea extract daily for eight weeks reduced total cholesterol by 3.9% and LDL cholesterol by 4.5% ().
Given that high blood pressure and high blood fat levels are risk factors for heart diseases, regulating them can promote heart health.
Summary:The catechins in green tea may help reduce blood pressure and improve blood fat levels, which promotes heart health.
The antioxidants in green tea extract, especially EGCG, have been shown to protect brain cells from oxidative stress ().
This protection can help reduce brain damage that could lead to mental decline and brain diseases like Parkinson’s, Alzheimer’s and dementia (, , ).
Furthermore, green tea extract can decrease the action of heavy metals like iron and copper, both of which can damage brain cells (, ).
It’s also been shown to help memory by enhancing the connection between different parts of the brain.
One study had 12 people drink a soft drink containing 27.5 grams of green tea extract or a placebo. Then, while the participants worked on memory tests, brain images were obtained to assess brain function.
The green tea extract group showed an increase in brain function and improved task performance, compared to the placebo group ().
Summary:Green tea extract has been shown to have a positive effect on brain health and memory, and may help protect against brain diseases.
Green tea extract is rich in catechins, and it contains a decent amount of caffeine.
Interestingly, it seems that this combination of ingredients is responsible for its weight loss properties (, , , ).
Both catechins and caffeine have been shown to assist in weight loss by regulating the hormones that can enhance thermogenesis (, , ).
Thermogenesis is the process by which your body burns calories to digest food and produce heat. Green tea has been shown to boost this process by making your body more effective at burning calories, which can lead to weight loss ().
One study had 14 people take a capsule containing a mixture of caffeine, EGCG from green tea and guarana extract before each meal. It then examined the effect on calorie burning.
It found that the participants burned 179 more calories, on average, in the following 24 hours ().
Another study showed that 10 healthy men burned 4% more calories during the 24 hours after consuming a green tea extract capsule containing 50 mg of caffeine and 90 mg of EGCG ().
What’s more, a 12-week study that had 115 overweight women take 856 mg of green tea extract daily observed a 2.4-lb (1.1-kg) weight loss among participants ().
Summary:Green tea extract can aid weight loss by increasing the number of calories your body burns through thermogenesis.
The catechins in green tea extract may also help reduce inflammation caused by some liver diseases like non-alcoholic fatty liver disease (NAFLD) (, ).
One study gave 80 participants with NAFLD either 500 mg of green tea extract or a placebo daily for 90 days ().
The green tea extract group showed significant reductions in liver enzyme levels, which is an indication of improved liver health ().
Similarly, 17 patients with NAFLD took 700 ml of green tea, which contained at least 1 gram of catechins, daily for 12 weeks. They had significant decreases in liver fat content, inflammation and oxidative stress ().
Interestingly, it’s important to stick to the recommended dosage for green tea extract, as exceeding it has been shown to be harmful to the liver ().
Summary:Green tea extract seems to help improve liver function by decreasing inflammation and oxidative stress.
The maintenance of your body’s tissues and organs is characterized by cell death and regrowth. Specialized cells known as stem cells produce new cells to replace those that die. This process keeps cells active and healthy.
However, when this balance is disrupted, cancer can occur. This is when your body starts producing dysfunctional cells, and cells don’t die when they should.
The antioxidants in green tea extract, especially EGCG, seem to have favorable effects on the balance of cell production and death (, , ).
One study explored the effects of taking 600 mg of green tea catechins per day for a year on patients at risk of developing prostate cancer.
It found that the likelihood of developing cancer was 3% for the green tea group, compared to 30% for the control group ().
Summary:Green tea extract has been shown to help maintain cell health. It may even help prevent some types of cancer, though more research is needed.
Whether taken as a supplement or applied to the skin, green tea extract has been shown to improve skin health ().
A large review demonstrated that when applied to the skin, green tea extract can help treat a variety of skin problems, such as dermatitis, rosacea and warts. Also, as a supplement, it has been shown to help with skin aging and acne (, , ).
For example, a study showed that consuming 1,500 mg of green tea extract daily for four weeks resulted in significant reductions in red skin bumps caused by acne ().
Moreover, both supplements and the topical application of green tea extract seem to help prevent skin conditions like loss of skin elasticity, inflammation, premature aging and cancer caused by exposure to UV rays (, ).
A study in 10 people revealed that applying a cream containing green tea extract to the skin for 60 days resulted in improved skin elasticity ().
Additionally, a study showed that applying green tea extract to the skin reduced skin damage caused by sun exposure ().
Interestingly enough, adding green tea extract to cosmetic products has been shown to benefit the skin by providing a moisturizing effect ().
Summary:Green tea extract has been shown to help prevent and treat several skin conditions.
Green tea extract seems to be helpful in exercise, whether it’s by improving exercise performance or enhancing recovery.
While exercise has many health benefits, it’s known to produce oxidative stress and damage cells in the body.
Fortunately, antioxidants like green tea catechins can reduce cellular damage and delay muscle fatigue (, , ).
In fact, a study in 35 men showed that green tea extract combined with strength training for four weeks enhanced the body’s antioxidant protection ().
Additionally, 16 sprinters who took green tea extract for four weeks demonstrated increased protection against oxidative stress produced by repeated sprint bouts ().
Furthermore, green tea extract seems to benefit exercise performance.
One study found that 14 men who consumed green tea extract for four weeks increased their running distance by 10.9% ().
Summary:Green tea extract increases antioxidant protection against oxidative damage caused by exercise. This translates to better exercise performance and recovery.
The catechins in green tea, especially EGCG, have been shown to enhance insulin sensitivity and regulate the production of blood sugar, both of which can lower blood sugar levels (, ).
A study gave 14 healthy people a sugary substance and 1.5 grams of green tea or a placebo. The green tea group experienced better blood sugar tolerance after 30 minutes, and continued to show better results, compared to the placebo group ().
Another study showed that green tea extract improved insulin sensitivity in healthy young men by 13% ().
Moreover, an analysis of 17 studies concluded that green tea extract is useful in decreasing fasting blood sugar levels. It can also help lower levels of hemoglobin A1C, which is an indicator of blood sugar levels over the past 2–3 months ().
Summary:Green tea extract has been shown to increase insulin sensitivity and blood sugar tolerance, all while decreasing hemoglobin A1C and blood sugar levels.
Green tea extract can be found in liquid, powder and capsule forms.
The liquid extract can be diluted in water, while the powder can be mixed into smoothies. However, it has a strong taste.
The recommended dosage of green tea extract is between 250–500 mg per day. This amount can be obtained from 3–5 cups of green tea, or about 1.2 liters.
But it’s important to know that not all green tea extract supplements are created equal. Some supplements contain only dry green tea leaves, while others contain isolated forms of one or more catechins.
The catechin most closely linked to the health benefits of green tea extract is EGCG, so you’ll want to make sure that the supplement you are consuming contains it.
Finally, it’s best to take green tea extract with foods. Both exceeding the recommended dose and taking it on an empty stomach may cause serious liver damage (, ).
Summary:Green tea extract can be consumed in capsule, liquid or powder form. The recommended dose is 250–500 mg taken with food.
Thanks to its high antioxidant content, green tea extract has been shown to help improve health and body composition.
Many studies have shown that green tea extract can promote weight loss, blood sugar regulation, disease prevention and exercise recovery.
It can also help keep your skin and liver healthy, reduce blood fat levels, regulate blood pressure and improve brain health.
It can be consumed in capsule, liquid or powder form. The recommended dose is 250–500 mg a day, and it is best taken with food.
Whether you want to improve your general health or decrease your risk of disease, green tea extract is an easy way to add health-boosting antioxidants to your diet.