10 Evidence-Based Benefits of Green Tea

Green tea is loaded with antioxidants. Among its benefits, it may help support brain function and fat loss, help reduce the chance of developing heart disease, and offer some protection against cancer.

Green tea is touted to be one of the healthiest beverages on the planet that may have many potential health benefits.

Here are 10 possible health benefits of green tea.

1. Contains healthy bioactive compounds

Green tea is more than just a hydrating beverage.

The green tea plant contains a range of healthy compounds that make it into the final drink (1Trusted Source).

Tea is rich in polyphenols, which are natural compounds that have health benefits, such as reducing inflammation and helping to fight cancer.

Green tea contains a catechin called epigallocatechin-3-gallate (EGCG). Catechins are natural antioxidants that help prevent cell damage and provide other benefits.

These substances can reduce the formation of free radicals in the body, protecting cells and molecules from damage. These free radicals play a role in aging and many types of diseases.

EGCG is one of the most powerful compounds in green tea. Research has tested its ability to help treat various diseases. It appears to be one of the main compounds that gives green tea its medicinal properties (2Trusted Source).

Green tea also has small amounts of minerals that can benefit your health.

Try to choose a higher quality brand of green tea, because some of the lower quality brands can contain excessive amounts of fluoride (3Trusted Source).

That being said, even if you choose a lower quality brand, the benefits still outweigh any risk.

2. May improve brain function

Green tea does more than just keep you alert, it may also help boost brain function.

The key active ingredient is caffeine, which is a known stimulant.

It doesn’t contain as much as coffee, but enough to produce a response without causing the jittery effects associated with taking in too much caffeine.

Caffeine affects the brain by blocking an inhibitory neurotransmitter called adenosine. This way, it increases the firing of neurons and the concentration of neurotransmitters like dopamine and norepinephrine (4Trusted5)Source5Trusted Source

Research has consistently shown that caffeine can improve various aspects of brain function, including mood, vigilance, reaction time, and memory (6Trusted Source).

However, caffeine isn’t the only brain-boosting compound in green tea. It also contains amino acid L-theanine, which can cross the blood-brain barrier (7)

L-theanine increases the activity of the inhibitory neurotransmitter GABA, which has anti-anxiety effects. It also increases dopamine and the production of alpha waves in the brain.Trusted SourcTrusteSourStudies show that caffeine and L-theanine can have synergistic effects. This means that the combination of the two can have particularly powerful effects in improving brain function (10

Trusted SourcSourcBecause of the L-theanine and the small dose of caffeine, green tea may give you a much milder and different kind of buzz than coffee.

Many people report having more stable energy and being much more productive when they drink green tea, compared with coffee.

3. Increases fat burning

If you look at the ingredients list for any fat burning supplement, chances are, green tea will be on there.

This is because, according to research, green tea can increase fat burning and boost metabolic rate (12

In one study involving 10 healthy men, taking green tea extract increased the number of calories burned by 4%. In another involving 12 healthy men, green tea extract increased fat oxidation by 17%, compared with those taking a placebo (13Trusted SourceTrusted Source

However, some studies on green tea don’t show any increase in metabolism, so the effects may depend on the individual and how the study was set up Trusted Source

Caffeine may also improve physical performance by mobilizing fatty acids from fat tissue and making them available for use as energy Trusted Source17Trusted Source

Two separate review studies reported that caffeine may increase physical performance by approximately 11–12% (18Trusted Sourc19Trusted Source).

4. Antioxidants may lower the risk of some cancers

Cancer is caused by uncontrolled growth of cells. It’s one of the world’s leading causes of death.

Research has shown that oxidative damage can lead to chronic inflammation, which can lead to chronic diseases, including cancers. Antioxidants can help protect against oxidative damage (20Trusted Source).

Green tea is an excellent source of powerful antioxidants.

Research has linked green tea compounds with a reduced risk of cancer, including the following studies:

• Breast cancer. A comprehensive review of observational studies found that women who drank the most green tea had an approximately 20–30% lower risk of developing breast cancer, one of the most common cancers in women (21Trusted Source).
• Prostate cancer. One study observed that men drinking green tea had a lower risk of advanced prostate cancer 
• Colorectal cancer. An analysis of 29 studies showed that those drinking green tea were around 42% less likely to develop colorectal cancer Trusted Source

Many observational studies indicate that green tea drinkers are less likely to develop several types of cancer, but more high quality research is needed to confirm these effects Trusted Source

To get the most health benefits, avoid adding milk to your tea. Some studies suggest it can reduce the antioxidant value in some teas.Trusted Source

5. May protect the brain from aging

Not only can green tea improve brain function in the short term, it may also protect your brain as you age.

Alzheimer’s disease is a common neurodegenerative disease and the most common cause of dementia in older adultsTrusted Source

Parkinson’s disease is another common neurodegenerative disease and involves the death of dopamine-producing neurons in the brain.

Several studies show that the catechin compounds in green tea can have various protective effects on neurons in test tubes and animal models, possibly lowering the risk of dementia.Trusted Source29Trusted Sourc30Trusted Source

6. May reduce bad breath

The catechins in green tea also have benefits for oral health.

Test-tube studies suggest that catechins can suppress the growth of bacteria, potentially lowering the risk of infectionsTrusted SourcTrusted SourcTrusted Source

Streptococcus mutans is a common bacterium in the mouth. It causes plaque formation and is a leading contributor to cavities and tooth decay.

Studies indicate that the catechins in green tea can inhibit the growth of oral bacteria in the lab, but no evidence shows that drinking green tea has similar effects.Trusted SourceTrusted SourcTrusted Sourc38Trusted Source

However, there’s some evidence that green tea may reduce bad breath.Trusted Source40Trusted Source

7. May help prevent type 2 diabetes

The rates of type 2 diabetes are increasing in recent decades. The condition now affects about 1 in 10 Americans (41Trusted Source).

Type 2 diabetes involves having elevated blood sugar levels, which may be caused by insulin resistance or an inability to produce insulin.

Studies show that green tea may improve insulin sensitivity and reduce blood sugar levels (42Trusted Source).

One study in Japanese individuals found that those who drank the most green tea had an approximately 42% lower risk of type 2 diabetesTrusted Source

According to a review of 7 studies with a total of 286,701 individuals, tea drinkers had an 18% lower risk of diabetes (44Trusted Source).

8. May help prevent cardiovascular disease

Cardiovascular diseases, including heart disease and stroke, are the leading causes of death worldwide.

Studies show that green tea may improve some of the main risk factors for these diseases, which includes improving total cholesterol and LDL (bad) cholesterol levels.

Green tea also increases the antioxidant capacity of the blood, which protects the LDL particles from oxidation, which is one part of the pathway toward heart disease .

Given the beneficial effects on risk factors, it may not be surprising that people who drink green tea have up to a 31% lower risk of dying from a cardiovascular disease.Trusted SourcTrusted Source

9. May help you lose weight

Given that green tea can boost the metabolic rate in the short term, it makes sense that it could help you lose weight.

Several studies show that green tea may help reduce body fat, especially in the abdominal area.Trusted Source

One of these studies was a 12-week randomized controlled study involving 240 people with obesity.

In this study, those in the green tea group had significant decreases in body fat percentage, body weight, waist circumference, and belly fat, compared with those in the control group (54Trusted Source).

However, some studies don’t show a statistically significant increase in weight loss with green tea, so researchers need to perform further studies to confirm this effect.Trusted Source

10. May help you live longer

Given that some compounds in green tea may help protect against cancer and heart disease, it makes sense that it could help you live longer.

In one study, researchers studied 40,530 Japanese adults over 11 years. Those who drank the most green tea — 5 or more cups per day — were significantly less likely to die during the study period:Trusted Source

• Death of all causes: 23% lower in women, 12% lower in men
• Death from heart disease: 31% lower in women, 22% lower in men
• Death from stroke: 42% lower in women, 35% lower in men

Another study involving 14,001 older Japanese individuals found that those who drank the most green tea were 76% less likely to die during the 6-year study period