What are the health benefits of green tea?
People have hailed the health benefits of green tea for centuries. Studies suggest that consuming green tea may positively affect skin health, help with weight loss, and reduce the risk of cardiovascular disease, among other benefits.
This tea comes from unoxidized leaves of the Camellia sinensis bush. It is one of the least processed types of tea, containing the most antioxidants and beneficial polyphenols.
Some research suggests this tea may positively affect weight loss, liver disorders, type 2 diabetes, Alzheimer’s disease, and more. However, more evidence is necessary for researchers to definitively prove these health benefits.
In countries with high this tea consumption, some cancer rates tend to be lower. However, human studies have not shown consistent evidence that drinking green tea reduces the overall risk of cancer.
A 2020 database review Trusted Source of epidemiological and experimental studies in humans produced inconsistent results and limited evidence of green tea’s benefits for lowering cancer risk.
The researchers assessed 142 completed studies, including 1.1 million participants.
The topical application of green tea polyphenol extracts may have a role in protecting the skin from UVB radiation. A 2018 review Source of in vitro, in vivo, and human studies demonstrated the potential benefits of tea polyphenols in the chemoprevention of UVB-induced skin cancer.
A 2020 review Source suggests this tea catechins have some positive impacts on the following types of cancer:
Overall, more research on humans is necessary to prove the benefit of this type of tea on the overall risk of cancer.
A 2021 review Source suggests green tea and the catechin epigallocatechin gallate (EGCG) it contains may help people with obesity to reduce their body weight.
A further meta-analysisTrusted Source of several different tea polyphenols-induced weight loss mechanisms suggested that catechins and caffeine synergistically produced weight loss effects, as opposed to them being the result of caffeine alone.
However, the impact of drinking green tea on weight loss is unlikely to be of clinical importance. Most studies that have shown small changes in metabolism used tea extracts with extremely high concentrations of catechins.
Learn more about green tea and weight loss.
Heart health benifits
A 2022 reviewTrusted Source suggests green tea catechins have anti-inflammatory properties that target free radicals and protect heart health.
A 2022 studyTrusted Source of 18,609 Japanese participants found no correlation between this tea consumption and death from heart disease, regardless of blood pressure levels.
Another 2022 studyTrusted Source associated green tea consumption with a lower risk of the following conditions:
- heart disease
- heart failure
- hypertension
- ischemic stroke
Separate reviews from 2017Trusted Source and 2019Trusted Source also found that the polyphenols in this tea may lower blood pressure, decrease inflammation, and improve epithelial function, which can help reduce heart disease risk in people with excess weight or obesity.
Lower cholesterol
A 2020 reviewTrusted Source concluded that tea consumption can significantly lower total cholesterol and low-density lipoprotein cholesterol in people with moderate weight, overweight, or obesity.
However, the authors highlight the need for more research, particularly longer studies with more diverse populations.
Type 2 diabetes
Studies concerning the relationship between green tea and diabetes have been inconsistent.
Some have suggested a lower risk of type 2 diabetes in people who drink this tea than in those who consume no tea.
One studyTrusted Source of people with and without diabetes in China associates daily green tea consumption with a lower risk of type 2 diabetes. It also associated daily this tea consumption with a lower risk of all-cause mortality in people with diabetes.
A further 2017 review of dietary polyphenol studies also associated tea, as part of the Mediterranean diet, with a reduced risk of type 2 diabetes.
However, further research is necessary to fully determine the relationship between diabetes risk and this tea.