We all know that it’s good and healthy to drink water, but did you know there are health benefits to drinking tea as well? Especially green tea – the second most popular type of tea that people drink. 
Green tea can trace its history all the way back to the Han Dynasty of China, when people drank it for medicinal purposes. They would use it to reduce inflammation, aid digestion, or heal wounds. There was even a book released by scholar Lu Yu about the art of drinking green tea, while the Chinese nobility developed a ritualistic preparation: the tea ceremony. 
But what makes green tea so good for our physical and mental well-being? Let’s talk about the different health benefits of green tea and what makes it so good for your longevity.
What is green tea?
Green tea (or unoxidised tea) is made from the leaves of Camellia sinensis, the tea plant. This evergreen shrub originates from China’s southwest forest region, where it grows in cool temperatures at high elevations. There are different types of green tea, such as the Chinese gunpowder tea or the Japanese matcha.
Farmers hand-pluck the tea leaves, which they then immediately preserve using steam or heat after harvest. This prevents them from oxidising and maintains the green colour, due to higher concentrations of chlorophyll and antioxidants.
Green tea does not require additives when drinking, which may adversely affect its health benefits. You can brew it in water at temperatures of 65–82ºC, and the brewing time depends on the type of tea. If you let it steep too long, however, the tea may become bitter.
Black tea and coffee have higher levels of caffeine than green tea (with some exceptions such as matcha, which is a highly concentrated form of green tea). The average amount of caffeine in 236ml (8oz) of green tea is 12–75mg. 
Green tea’s nutritional value
In 473ml (16oz) of green tea, you have 0kCal due to 0g of fat, 0mg of cholesterol, and 0g of carbohydrates. It does, however, contain sodium, calcium, phosphorus, potassium, and zinc. The beverage itself consists mostly of water.
Regarding caffeine, green tea has about 56.8mg per 16oz. 
Health benefits of green tea
Several promising studies and research papers have looked into the health benefits of consuming between 2–5 cups of green tea in a day. There are several associations to improvements in a person’s physical and mental well-being due to the bioactive components of green tea.
- High levels of polyphenols
Polyphenols are chemicals that occur naturally in plants. Green tea is rich in polyphenols called flavonoids, which are known for their health benefits. They’re currently indispensable in several nutraceutical, pharmaceutical, medicinal, and cosmetic applications due to their antioxidative, anti-inflammatory, and anti-carcinogenic characteristics.
There is now plenty of ongoing research to try and isolate flavonoids and other potential applications in bio-medical fields, such as medicines that prevent chronic diseases. 
- Improved cognitive function
Caffeine is a stimulant which increases your neural activity alongside the concentration of neurotransmitters. In particular, it increases the concentration of dopamine and norepinephrine by blocking adenosine uptake in your brain.
By doing this, it improves your mood, alertness, reaction time, and even memory functions. 
- Boosted metabolism
Caffeine has a thermogenic effect, which is associated with body weight reduction and increased fat metabolism. Meanwhile, green tea also contains catechins that may trigger thermogenesis, which leads to fat oxidation. This means that green tea in particular has successful applications in weight loss regimens and preventing weight regain. 
- Decreased risk of cardiovascular disease
While there is little long-term research into the subject, some research may suggest that the antioxidants in green tea aids in lowering blood pressure and LDL cholesterol levels. This helps reduce your risk of developing cardiovascular diseases.
Some research has even suggested that consuming 5 cups of green tea a day may reduce your risk of mortality via cardiovascular disease by about 26%. 
- Lowered cholesterol
Green tea has shown results in reducing LDL cholesterol oxidation and suppressing lipoxygenase activity. This has shown that the bioactive components in green tea – such as non-fermented Chinese green tea – may reduce LDL cholesterol levels in our systems. 
- Reduced oxidative stress
The flavonoids in green tea act as antioxidants, which work to combat oxidative stress in our bodies. Oxidative stress can alter DNA and cause damage to our cellular systems.
People naturally produce free radicals through cellular metabolism, but we often pick up excess amounts from external sources, including pollution or medication. When excess free radicals accumulate, they cause “oxidative stress,” which has a key role in age-related degeneration. 
Through the intake of foods and beverages high in antioxidants, we can neutralise these free radicals and therefore minimise the effect of oxidative stress on our bodies. This includes drinking green tea regularly.
- Improved insulin sensitivity
Green tea consumption has been shown to significantly reduce fasting glucose and haemoglobin concentrations in people’s bodily systems. Recent studies have suggested that green tea extract can lower fasting plasma concentrations of glucose and insulin in lab settings.
Green tea has also been shown to reduce fasting insulin concentrations. 
- Inhibition of oral bacteria
Green tea’s antioxidative properties aren’t just good for our blood sugar or metabolism – they’re also good for our oral health! The catechins in green tea prevent bone resorption and inhibit the growth of bacteria that are associated with periodontal diseases. This includes the Streptococcus mutans bacterium that causes plaque and contributes to tooth decay. 
- Reduced inflammation
Green tea leaves are an excellent source of epigallocatechin 3-gallate (EGCG), which has anti-inflammatory effects. When applied topically, green tea extract can reduce inflammation in your skin. Meanwhile, people regularly consume it to aid in their arthritis. 
- Prevention of skin cancer
There is a correlation between green tea consumption and lower cancer rates in countries where green tea consumption rates are high. Additionally, some research has shown that the polyphenols in tea may protect the skin from UVB radiation, which helps prevent UVB-induced skin cancer. 
- Increased longevity
Summing up all of the above benefits shows that green tea has positive effects on your health and mortality rates, which all add to your longevity. In fact, one study showed that people who consume 5 or more cups of green tea a day had lower mortality rates overall than those who drank less. 
Green tea and longevity
If this isn’t enough to convince you to include green tea in your diet, then we don’t know what will. You can find it in many forms, from plain tea to supplements to concentrated extract. Much like avocado is considered a superfood, green tea may be a “superdrink” – and one of the healthiest beverages you can consume.
From improved alertness and cognitive function to reduced inflammation, there are many benefits to drinking green tea regularly. Find your favourite way to consume green tea (matcha is very popular!) and make it an everyday staple to boost your overall health.