Green tea is one of the most widely consumed herbs in the world.
It has been used for thousands of years. Historically, green tea was used as a daily beverage and in Traditional Chinese Medicine (TCM) for treating various ailments.
Modern research has shown that green tea and its compounds may offer numerous health benefits, especially for metabolism, brain health, inflammation, heart health, and more.
This article will detail the health benefits of green tea, its major bioactive compounds, and how to incorporate it into one’s diet.
Table of Contents
What is Green Tea?
Green tea, a popular type of herbal tea, comes from the leaves of the tea tree, which is scientifically known as Camelia sinensis.
The tea plant is a small, evergreen shrub native to the mountainous regions of Japan and China.
Green tea is rich in many different bioactive compounds, such as:
- Flavonols, especially the catechins
- Phenolic acids
- Caffeine
- Flavandiols
- Chlorophyll
- Carotenoids
- Vitamins, including vitamin C, vitamin E, and beta-carotene
- Potassium and other minerals
Out of all of these compounds, the ones with the most researched health benefits are the catechins, a group of natural antioxidants.
There are four primary catechins that are found in green tea, they include:
- epigallocatechin-3 gallate (EGCG)
- epigallocatechin (EGC)
- epicatechin gallate (ECG)
- epicatechin (EC).
Among these, EGCG takes up nearly 60% of the total catechin content, and it also appears to be the most beneficial catechin in terms of health effects. It has been shown to benefit weight loss, antioxidant function, and more.
Green tea is also considered a beneficial herbal tea for upset stomach.
Health Benefits of Green Tea:
Green tea and its compounds, especially EGCG and other catechins, have received a lot of research attention in recent years. Many studies, including tremendous clinical evidence, show that green tea benefits the body in a number of different ways.
In particular, green tea is associated with the following health benefits:
1. May Support Weight Loss
A substantial amount of research shows that green tea benefits weight loss and metabolism.
In one clinical trial of 115 women with obesity, those who took a high-dose green tea extract lost significantly more weight compared to the placebo. Additionally, the green tea group had significantly lower levels of ghrelin, a hormone involved in feelings of hunger and metabolism, among other things.
In another clinical trial in 120 overweight adults, supplementing with a green tea meal replacement formula for 12 weeks helped with weight loss and body fat reduction compared to the placebo. Moreover, those who received the green tea formula had significantly lower cholesterol levels.
Also, a clinical study done on 70 women with metabolic syndrome showed that the women who were given green tea daily for eight weeks had significantly lower waist circumference, body mass index (BMI), and waist-to-hip ratio compared to the placebo. Those who consumed green tea also significantly improved systolic blood pressure, blood sugar, and LDL cholesterol.
Another clinical trial in 60 obese subjects found that those who supplemented with green tea for 12 weeks had significant weight loss compared to the control group. The researchers also noted that individuals who consumed green tea had significantly higher resting energy expenditure and fat oxidation. These factors increase calorie burning, which makes losing weight easier.
To be fair, not all studies have shown benefits, however. For example, one clinical trial involving 78 obese women found no significant difference in weight loss, BMI, and waist circumference in women who were supplemented with green tea extract or a placebo for 12 weeks.
Summary:
Clinical human research has found that green tea supplementation may be beneficial for reducing body fat and aiding in weight loss.
2. May Support Blood Pressure & Heart Health
A number of studies show that green tea may benefit overall heart health by improving blood pressure, lowering cholesterol, and reducing other cardiovascular risk factors.
In a clinical trial involving 20 obese women with high blood pressure, those who were given 500mg of green tea extract for four weeks had significant reductions (2 to 5mmHg) in systolic blood pressure compared to the placebo group.
In another clinical trial in 58 obese, hypertensive individuals, supplementation with 379mg of green tea extract for three months was associated with significant reductions in systolic and diastolic blood pressure. Those who took green tea also had significantly improved cholesterol, triglyceride, inflammation, and antioxidant profiles.
In a 12-week clinical trial in 240 adults with obesity, those who were given a high-dose green tea extract (583mg of catechins) had significant reductions in systolic blood pressure, body fat, and LDL cholesterol compared to the placebo. Altogether, green tea extract supplementation appeared to reduce key cardiovascular risk factors.
Additionally, a clinical study in 111 healthy adults showed that supplementation with Camellia sinensis capsules was associated with significant reductions in numerous cardiovascular risk factors compared to placebo. For example, the treatment group had significantly lower blood pressure, cholesterol levels, and inflammation compared to the control group.
However, another clinical study in 51 healthy subjects found no significant difference in blood pressure, cholesterol, or other heart health risk factors after supplementing with either a low (100mg) or high (400mg) dose of green tea catechins. One possible explanation