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.
Green 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 green 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.
This article lists some potential health benefits and types of green tea, its nutrition content, and the potential side effects.
In countries with high green 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.
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The researchers assessed 142 completed studies, including over 1 million participants.
The topical application of green tea polyphenol extracts may have a role in protecting the skin from UVB radiation. A
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Overall, more research on humans is necessary to prove the benefit of green tea on the overall risk of cancer.
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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 green tea extracts with extremely high concentrations of catechins.
Green tea has anti-inflammatory properties.
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A 2019 review also found that the polyphenols in green tea may lower blood pressure, decrease inflammation, and improve endothelial function, which can help reduce heart disease risk.
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However, the authors highlight the need for more research, particularly longer studies with more diverse populations.
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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 green tea than in those who consume no tea.
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However, another long-term study of 119,373 adults without diabetes in China suggests that people who drank green tea had a higher risk of type 2 diabetes than those who did not drink it.
The researchers suggest the risk increased with the amount of tea and duration of drinking it.
Further research is necessary to fully determine the relationship between diabetes risk and green tea.
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This may be due to the neuroprotective effects, including anti-inflammation and anti-oxidative stress, of certain catechins in green tea.
However, further research is necessary to strengthen this evidence.
Green tea may also benefit other conditions. For example, the United States Food and Drug Administration (FDA) has
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- prevent tooth decay
- improve osteoarthritis pain
- antiallergic effect
- promote wound healing
However, further human clinical trials are necessary to firm up these theories.
Since green tea also contains small amounts of caffeine, some people may enjoy it as a substitute for coffee or other caffeinated drinks.
Unsweetened brewed green tea contains fewer than
Green tea contains a relatively small amount of caffeine, approximately 29 milligrams (mg) per 8-ounce cup, compared with black tea, which has
The caffeine in a cup of tea can vary according to the duration of infusing time and the amount of tea infused.
Green tea contains one of the highest amounts of antioxidants of any tea. Green tea consists of
Green tea is available in many types and forms, including:
- bottled and sweetened with sugar or an artificial sweetener
- single tea bags
- loose leaf
- instant powder
- green tea supplements, in capsule form or as liquid extracts
In adults, there are
- Caffeine sensitivity: People with severe caffeine sensitivities could experience symptoms such as insomnia, anxiety, irritability, nausea, or an upset stomach after drinking green tea.
- Liver damage: Consuming a high concentration of green tea extract may adversely affect liver health in
rare casesTrusted Source . - Other stimulants: If a person consumes green tea alongside stimulant drugs, it may increase their blood pressure and heart rate.
Most research suggests that the rare cases of liver injury from green tea extract consumption are idiosyncratic reactions. Reviews of these instances have yet to conclude direct causality.
The FDA does not regulate green tea supplements. As a result, these supplements may contain other substances that are unsafe for health or have unproven health benefits.
Always check with a doctor before starting any herb or supplement regimen.
Further research is necessary to determine the best time to drink green tea. However, since green tea contains caffeine, some people may prefer to drink it in the morning.
Research suggests adults may tolerate up to 24 cups of green tea daily, although this is not necessarily a recommended daily intake. People should be aware of the amount of caffeine in the brand they choose.
Very high quantities of green tea may lead to liver damage or interact with certain medications.
Some research suggests that regular tea consumption, including green tea, may help to reduce body weight and waist-to-hip ratios. However, several factors can influence fat loss, including total calorie intake and exercise levels.
Green tea may have several health benefits. For example, it may help with weight management, skin inflammation, and type 2 diabetes risk. Some research also links green tea consumption to improved cardiovascular health.
Green tea has one of the highest concentrations of antioxidants of any tea. It is naturally low in calories and contains less caffeine than black tea and coffee.
Most people can drink green tea daily with no side effects. However, some people may experience sleep disturbances due to the caffeine in green tea if they drink large amounts or consume it late in the day.
