Green tea has long been on menus around the world. Originating in China as early as 2737 B.C., it’s made of the same tea leaves as black and oolong teas, from the leaves of the Camellia Sinensis plant. However, it hasn’t gone through the traditional oxidation process that results in other teas turning black. Instead, green tea is made by steaming, frying and drying the leaves.
Traditionally used as a Chinese medicine, it’s now popular across the world, after being introduced to Europe in the 17th Century by Portuguese and Dutch traders. It’s become famous for being a drink with plenty of health benefits – far more so than other teas.
What are the potential health benefits of green tea?
Whether you’re looking to boost a particular part of your health, or simply want to swap your standard caffeinated coffee for a lower-caffeine alternative, green tea has long been lauded as one of the healthiest drinks on the market. Let’s explore the top reasons to add a cup to your daily routine.
Green tea and antioxidants
One of green tea’s biggest benefits is that it contains naturally-occuring antioxidants called polyphenols. Antioxidants can slow down (or in some cases, even prevent) cell damage, making them a powerful tool for boosting our health and wellness. As well as green tea, they can also be found in fruit and vegetables, which is why we are often told to make sure that we’re eating five portions of fruit and veg per day.
In particular, green tea contains the plant compound epigallocatechin gallate (EGCG). This powerful antioxidant may even inhibit the growth of certain types of cancer cells when used jointly with cancer drug treatment, according to some studies.
Green tea and weight loss
Many of us will be aware of the familiar rumor that green tea can aid weight loss. While it’s no shortcut to a slim physique, green tea does contain caffeine, a stimulant which has been shown by some studies to increase fat burning. Additionally, caffeine may boost exercise performance by reducing the rate of perceived exertion. This means it may just make you work harder at the gym, and thus burn more fat in the process, resulting in weight loss.
It could be argued that drinking a cup of coffee would give you a higher dosage of caffeine, but green tea has another benefit – it contains specific antioxidants called catechins. These have been shown to boost human metabolism in adults, reducing fat in the group that drank catechin-enriched green tea (which is high in antioxidants) across 12 weeks.
Green tea and brain function
The caffeine content in green tea may help keep us alert, increasing reaction time and helping reduce tiredness. This is because it’s a stimulant – it affects the central nervous system in the brain, causing it to produce more dopamine, which promotes increased focus. Additionally, caffeine blocks adenosine receptors in the body. Adenosine is the chemical that helps us feel sleepy, so ingesting caffeine stops this, and makes us feel more awake.
In addition to caffeine, green tea contains L-theanine, which has been shown to reduce anxiety and improve mental focus, especially when combined with caffeine. It can only be found in nature in mushrooms and in tea leaves.
Green tea and aging
In terms of long-term brain health, there is some evidence to suggest that green tea may reduce the risk of dementia and Alzheimer’s disease, but more research is needed before there is a confirmed link. Early findings suggest that you’d need to drink around three cups per day to stand a chance of green tea making a difference.
Green tea and blood sugar levels
At a basic level, green tea can be an amazing option when it comes to your daily tea or coffee habit. It’s traditionally served without milk or sugar, meaning that you reduce your daily added sugar intake, especially in comparison to drinking a glass of squash or fizzy drink.
Furthermore, there is some research to suggest that drinking several cups of green tea per day can help with insulin resistance in people with Type 2 diabetes. This is because the catechins in the tea decrease the absorption and digestion of carbohydrates (which break down into glucose in your blood). In those without diabetes, insulin works to control the absorption of glucose, but people with Type 2 diabetes can’t produce enough insulin themselves to manage their blood sugar levels, so they have to monitor and control it manually. Green tea may be able help slow down the digestion of carbohydrates to keep blood sugar levels more stable.
Green tea and heart health
The benefits of EGCG from green tea extend to heart health too, with the compound potentially able to dissolve this plaque that builds up in the blood vessels, according to research by the British Heart Foundation. Heart attacks and strokes can be caused by fatty material building up inside the body, which in advanced cases can then turn into these plaque deposits. Being able to reduce them and keep the blood flowing is vital for our health. However, the research also noted that you’d need to drink a significant amount of green tea to see these effects, making it hard to apply the findings to the real world. It may be that the structure of the EGCG compound needs to be altered to make it easier to absorb.
A small number of trials have also found that green tea has been shown to reduce total cholesterol levels, especially LDL (low density lipoprotein) cholesterol, which is often known as “bad” cholesterol. This is due to the antioxidants in the tea.
Green tea and skin
The antioxidants in green tea are also beneficial for your skin, both when drinking it and when adding it to your skincare routine in the form of a face mask. Antioxidants help combat free radicals, which are unstable atoms which damage cells in the body, causing aging and inflammation. Green tea can help reduce free radicals, helping your skin stay youthful.
The anti-inflammatory properties of the catechins in green tea may potentially also help with acne, although they cannot cure it completely. Again, the research focused on green tea supplements, meaning that you would need to drink a lot of green tea to mimic the effects.
Green tea and digestion
Having a healthy gut microbiome is crucial for our health. The microbiome is made up of thousands of microbes, which work together to improve digestion, keep your immune system functioning and destroy harmful bacteria. However, it can get altered as a result of disease and diet – too many processed and fatty foods are detrimental to our health.
However, green tea can add “good” bacteria to our guts, according to research by Ohio State University. Not only does having good gut bacteria help with digestion, but it also plays a role in weight management. The gut microbiome is vital in humans for knowing when we are hungry or satiated – if this is altered, it may eventually lead to overeating.
Green tea and rheumatoid arthritis
Rheumatoid arthritis (RA) is a painful condition, caused by the body’s immune system attacking healthy cells by mistake. In turn, this leads to inflammation, causing swollen joints. There’s currently no cure for the condition, meaning that sufferers need to work to manage their symptoms to give them the best quality of life.
There is some evidence to suggest that the anti-inflammatory properties of EGCG in green tea could help reduce the inflammation caused by arthritis, although research has tended to focus on green tea extract, and combining green tea with other methods, such as exercise. However the antioxidants in green tea may help with overall health, which in turn may help with RA, according to older studies.
Green tea and dental health
Our teeth are a small but important part of our bodies – so any infection or inflammation can be both painful but also detrimental to our ability to eat. Green tea is traditionally served unsweetened, helping us reduce our sugar intake in the first place, but the antioxidants in green tea also have the potential to kill bacteria. This can reduce the risk of dental plaque and therefore tooth decay, according to some research.
Green tea may also have the potential to combat bad breath, according to older research by the University of British Columbia. It is thought this is because the catechins in the tea may kill the microbes in our mouths that cause smelly breath.
Can green tea help with our health?
In conclusion, green tea may have some health benefits for some people. However, far more research needs to be done before any solid conclusions can be drawn. Additionally, it may be that green tea extract may be the solution, rather than just the drink – but adding a cup to your daily routine can certainly help you cut down on your sugar intake to start.