Green tea

Once unknown to the masses, green tea has become one of the essential morning rituals for millions of people today. The precision with which this brew fits into our lives has risen tea as a health-promoting beverage with much aesthetic value. Even if you hate its taste otherwise, you can’t deny, that this tea, as a beverage has a place in almost every household. 

Did you know?

The origin of tea dates back to thousands of years in ancient China. Where It is claimed to have been discovered “accidentally” and in a curious turn of events, by the mythical emperor Shennong. Interestingly, Shennong is also named the "Father of Chinese Medicine". So, was it an accident for real or a well-thought formula? The answer remains buried somewhere in the history for the tea lovers to explore. From China, the tea culture spread to Japan and soon it escaped to explore the whole world. In India, however, the actual history of tea isn’t as clear. From what is known, wild tea (could be green tea) was consumed in India long before it was commercialized by the British East India Company.

  1. How to make green tea
  2. Green tea types and use
  3. Benefits of green tea
  4. Green Tea Side Effects
  5. How many cups of green tea can be taken per day?
Doctors for Green Tea Benefits, Side Effects and Use

Brewing the perfect cup of tea:

Tea lovers have their own unique ways to brew their perfect cup of tea but here is a general method for preparing a warm cup of green tea for yourself:

  1. Put 2-3g of tea leaves in a pan/teapot.
  2. Pour the required amount of boiling water into the pan (20-100 ml depending on the tea and your desired flavours).
  3. Let it steep for a minute or two. (Some people like to steep it longer as per their taste)
  4. Strain and serve it hot.

But if you are too lazy, you can get rid of all of this pain by using a single cup tea bag and enjoy your tea hassle-free.

Used green tea bags can be applied topically to treat puffy eyes.

Matcha green tea is most popularly used in making face masks.1 tsp of the green tea powder can be mixed with ½ tsp of honey to make a rejuvenating face mask.

Did you ever wonder what exactly is green tea? Or if it is any different from your regular tea? If yes, where does it come from and how? Let's try and answer these queries one by one for you.

You’ll be astonished to know that all types of tea are made from a single type of plant, Camellia sinensis commonly called the “Tea plant”. The difference arises from the level of oxidation that the raw tea leaves have gone through. Ideally, black tea is the most oxidized and green tea is unoxidized. The famous Oolong tea is partially oxidized while there are some varieties of tea which are fermented but not always oxidized (Puerh tea).

Now, is the biological term oxidation coming in between you and your understanding of tea? let's explain. Oxidation is the absorption of oxygen by food, which causes changes in the biochemistry of the food, in this case, raw tea leaves. Ever noticed the apples turning brown when left cut? That is oxidation. Though, in case of preparing tea, oxidation is partly natural and partly done in controlled conditions by monitoring the temperature and humidity of the rooms. Once the leaves reach a specific level of oxidation, the process is stopped by a specific heating procedure. Now, oxidation is a natural process that can’t be stopped completely but it can be slowed down enough to give the tea a good shelf life.

Your regular tea is usually black tea boiled with milk and sugar added to it. There are some people who claim that the addition of milk and sugar does more harm than good for your health but an opposite claim exists as well. So, due to lack of scientific proofs, it is best to check with a nutritionist about what will suit your body type more. 

Herbal teas are prepared from various plants like Hibiscus, Jasmine, Chamomile instead of the tea plant. So, they are not considered green tea. However, a lot of green tea flavours are available in the market like mint tea, jasmine tea, lemon tea etc. It is always advisable to check the label for the genuinity of the product.

Loose green tea is commercially available with a lot of tea brands. However, if you are a tea enthusiast and looking for a particular variety of tea, you can easily buy it in the form of tea bags, green tea powder, capsules, and tablets.

Decaffeinated green tea is a kind of green tea which has been treated to remove its caffeine. While it is considered a better option for people who cannot tolerate caffeine, it reduces the number of antioxidants in the tea. But, there have been no studies to detect the difference between decaf green tea and normal green tea.

Types of Green Tea

The world of tea is probably as diverse as the type of people around the globe. If we start listing tea varieties it’ll probably take a whole new article to cover and who knows maybe more. Japan alone grows at least 10 famous varieties of tea. Still, for the sake of knowledge, we should study a few known varieties of green tea available in trade.

  • Sencha green tea:
    Sencha is the most common form of Japanese green tea and it is the easiest to prepare. To prepare it, raw tea leaves are steamed, rolled and dried to stop oxidation and to give them their traditional shape. The leaves are then boiled with a cup of water to be consumed.
  • Gyokuro green tea:
    This variety of tea differs from the sencha tea in processing. The plants are covered with a cloth at least 20 days before harvesting. This is done to reduce the number of catechins in the leaves which makes the tea more flavourful. Another variety of tea, Kabusecha, is grown in a very similar manner but the tea plant is only covered for a week.
  • Matcha green tea:
    Matcha tea is a grounded (powdered) form of another type of green tea which is known as Tencha. Tencha is grown in shade, just like Goykuro, but the covering time is much longer than 20 days and the leaves are dried without rolling. Tencha tea, when it is grounded just before it is shipped is called matcha.
  • Chinese gunpowder tea:
    This Chinese green tea gets its name from the distinct shape its leaves are rolled and dried into after its processed and steamed. It has a unique smokey flavour that is apt for its namesake.

The first thing that comes to mind before we jump on the green tea routine is: Is green tea healthy? Or is it just a bunch of new-age hype? Well, the good news is that green tea does indeed have a number of health benefits that are backed by scientific research. In fact, most of the health benefits of green tea can be attributed to a special class of organic compounds present in the tea leaves, known as catechins, which get dissolved in water when made into a brew. Let’s explore some of the benefits we can reap while sipping a warm cup of green tea.

  • Improves brain health: In a series of studies, green tea catechins have been found to stimulate brain cells, improving memory and cognition. This is also helpful in keeping neurodegenerative diseases like Alzheimer's at bay.
  • Good for cardiovascular system: Green tea improves metabolism and prevents plaque formation in arteries which is one of the major risk factors for heart attack and stroke. It also strengthens your heart muscles, which leads to an improved heart function.
  • Beneficial for skin: Green tea bags are the best remedy dark circles and puffy eyes. Its anti-inflammatory and antioxidant properties make sure that your skin looks healthy and shines with a vibrant glow.
  • Promotes weight loss: Green tea is rich in catechins and caffeine which increase BMI and an improved BMI is directly related to fat reduction and weight loss.
  • Improves oral health: Being an antibacterial, green tea catechins kill the harmful bacteria in your mouth thus preventing gum and teeth infections. Drinking green tea regularly also helps keep garlic breath at bay.

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Green tea benefits for brain

Do you know that your daily cup of tea makes your brain sharper? According to ayurvedic doctors, green tea is rich in caffeine, which has a direct stimulatory effect on the brain cells. A number of studies have been done to study the exact ways in which caffeine affects the functioning of our brain and most of them hint that caffeine blocks the action of a chemical called adenosine in our brain. Reduced adenosine levels lead to rise in the activity of brain cells. Studies suggest that moderate intake of caffeine is not only a brain stimulant but it also improves memory and brain coordination.

Read more: How to increase brain power

Green tea for weight loss

Did you recently hear about the effects of green tea on weight loss? Did someone explain to you how miraculous this supplement has been for them? Numerous research studies have been done on the efficiency of green in helping people to lose weight and they suggest that green tea is indeed effective in weight loss. Experts suggest that green tea contains catechins and caffeine, which, together, increase the metabolism of the body. And theoretically, increased metabolism makes our body to burn energy faster and break down more fat.

However, most of these studies are claimed to have used a lot more amount of catechins and caffeine than normally present in a single cup of green tea. According to doctors, green tea adds to the benefits of a regular exercise and healthy diet regime.

But quite contrary to its hype, if you are eating junk food and have an erratic lifestyle then green tea is not a miracle agent. For effective weight loss, It is advisable to exercise and eat healthy food along with green tea. 

Read more: Diet chart for weight loss

Green tea benefits for heart

Cardiovascular (related to the heart and circulatory system) diseases are becoming more and more prevalent in the recent century. With the rise in factors like pollution, obesity and stress, these diseases of the elderly are now affecting the younger generations equally.

Now, studies suggest that green tea could be helpful in mitigating the most common causes of heart problems.

According to researchers, free radicals (a type of oxygen formed in our body due to its own metabolic functions and in the effect of stress or pollution) combines with the LDL (low-density cholesterol) or bad cholesterol in our body and lead to the formation of plaques (fat deposits) in the arteries. This plaque narrows the blood vessels and leads to problems like stroke and heart attack. Green tea, as an antioxidant, scavenges the free radicals and stops this oxidation process thus, reducing the risk of the most common heart problems.

Read more: Best cardio exercises for heart health

Green tea is an effective antimicrobial

With the advancement of research, humans have developed antibiotics against most diseases. A lot of diseases that were once considered fatal are now curable thanks to the ever-developing technology. But this success has brought upon us an entirely different challenge in the form of drug-resistant microbes.

Read more: Antibiotic resistance

In such times, there is a need for more natural products that act on a wider scale and make it difficult for the microbes to develop resistance against them.  Studies have shown that green tea is very effective in countering fungal, viral, and bacterial infections. This property of green tea is attributed to the catechins present in it, which have been claimed to inhibit the growth of most microbes and can effectively kill the disease-causing bacteria.

Additionally, the antimicrobial effects of green tea have been found effective on drug-resistant bacteria like MRSA (Methicillin-resistant Staphylococcus aureus). However, research is still going on worldwide to find the perfect way of utilising this antimicrobial aspect of green tea in medical therapies.

Read more: Precautions to take with antibiotics

Green tea for bad breath

Do you suffer from bad breath? Do gum problems trouble you too? The good news is that the antibacterial properties of green tea may come right to your rescue. Doctors suggest that gum infections or teeth infection are the primary reasons for bad breath.

According to a research study, the catechins present in green tea kill the harmful bacteria in your mouth, thus mitigating the problem of bad breath. Additionally, the deodorant effect of green tea would help you deal with bad breath problems that come with eating certain kind of foods which are inherently rich in sulphur like onions or garlic.

Read more: How to get rid of bad breath

Green tea benefits for skin

Regular consumption of green tea may help you get glowing and clear skin naturally. Studies suggest that the antioxidant and anti-inflammatory properties of green tea make it an ideal anti-ageing food. Regular consumption of green tea is known to increase the number of antioxidants in the body which are the first line of defence against wrinkles, fine lines and other signs of premature ageing. Additionally, topical application of used green tea bags is a known remedy for puffy eyes.

According to medical practitioners, the caffeine in green tea constricts the nerves around eyes, which decreases the puffiness around eyes by increasing circulation in the eye area. So next time you need to relax after long hours of work, soothe your stressed eyes with a used bag of green tea.

Read more: Swollen eyes causes

Green tea benefits for hair

Green tea is a rich source of vitamins, especially vitamin B, vitamin C and vitamin E. Together, these vitamins help nourish hair follicles and promote hair growth. Additionally, Vitamin C is a strong anti-oxidant, which along with the catechins present in green tea, fight against hair loss caused by the oxidative damage to hair (damage caused by stress and pollution).

Both animal and lab studies suggest that topical application of green tea is very effective in the treatment of testosterone-induced hair loss and baldness in both males and females. However, due to lack of human evidence, it is suggested to check in with your doctor before using green tea as any kind of rinse or paste for your hair.

Read more: Best hair oil for men and women

Green tea benefits for diabetes patients

Recent studies claim that green tea increases insulin sensitivity in the body. Regular consumption of green tea makes this hormone (insulin) to take up more glucose from the blood thus reducing blood sugar levels in the body.

In a further study on the Japanese population, it was claimed that people who drink green tea every day have a significantly less chance of developing diabetes.

Read more: Insulin resistance symptoms

Green tea benefits in arthritis

According to a group of studies, green tea can be very useful in anti-arthritic therapies. These studies hint that green tea has a special class of biological compounds known as polyphenols especially EGCG (epigallocatechin-3 gallate), which is a potent anti-inflammatory and antioxidant. It reduces joint pain and swelling in joints, giving relief from two of the unbearable symptoms of arthritis.

A further study in the US confirmed the therapeutic value of EGCG in anti-arthritis treatments. The bone preserving qualities of EGCG has also been studied widely along with the effect of fluoride present in green tea in the alleviation of the symptoms of bone diseases like osteoporosis. However, there isn’t enough evidence on the dosage and administration of this drug or its possible effects on human health. So, arthritic patients are suggested to ask their doctor about the possible benefits of green tea for their condition.

Read more: What to eat and what not to eat if you have arthritis

Green tea benefits in alzheimer's

Diseases like Alzheimer's and Parkinson's are the most common neurodegenerative diseases (diseases that kill the brain cells) today. The degeneration of brain cells by these diseases cause symptoms like dementia and loss of cognitive function in humans. Recent researches hint that green tea extracts have a great therapeutic value in alleviating symptoms of most of these neurodegenerative diseases. The studies further suggest that the antioxidant property of green tea is in part responsible for the neuroprotective (protects brain cells and avoid damage of neurons) benefits of green tea.

Read more: Age-related memory loss symptoms

Green tea for autoimmune diseases

Autoimmune diseases are conditions where the immune system of a person creates antibodies against healthy cells. A weakened body and immune system become prone to a number of common infections. It must be noted that treating an immunocompromised person is more difficult than treating a normal person as their own immune system is acting against them.

According to an article published by Oregon State University, green tea is very useful in boosting immunity. The article suggests that certain compounds in green tea increase the levels of regulatory T cells (a kind of cells in the immune system which keeps the immune system from attacking the body’s own cells). Increase in the number of the regulatory T cells would, in turn, keep the immune system from attacking the body’s normal cells, thereby reducing the severity of the autoimmune disease.

Read more: Immunity boosting foods

Green tea anti cancer potential

Breast cancer is one of the leading causes of mortality in females all around the world. In spite of the presence of a number of drugs, it has been quite difficult to deal with this ever increasing problem, especially in people with a high risk (people who have breast cancer history in their family). Recent studies suggest that administration of green tea extracts along with the most commonly used drug for breast cancer is very potent in killing the cancer cells and inhibiting the spread of cancer. It was further suggested that catechins in green tea may be the anti-cancer agent.

Additionally, green tea is also being studied for its anti-cancer activity in bladder cancer and lung cancer, wherein it is claimed to be helpful in reducing the effect of radiation burns. However, not much evidence is available for its exact mode of action on the cancer cells, in the lack of proper evidence much research is still needed in this field.

Green tea is safe when consumed in moderate amounts but overconsumption may lead to a number of side effects:

  • Green tea has caffeine as one of its main component, dependence and withdrawal symptoms like anxiety, insomnia and restlessness have been noted in people who use the tea for the long term.
  • In some cases, liver damage has been found associated with the over-consumption of green tea. However, in a report published by the US Pharmacopoeia, it was mentioned that green tea extracts are only toxic when taken on an empty stomach. And some other recent researches suggest that green tea is not toxic to the liver at all. Hence, there is a lot of contradictory information. But, if you already have a weak liver, it’s better to refer to your doctor before taking green tea.

Read more: Liver disease symptoms

  • Green tea is known to interfere with the action of certain therapeutic drugs and herbal remedies. So, if you are already on prescribed medication, it’s always advisable to talk to your doctor before taking green tea.
  • If you are anaemic, it’s preferable not to drink green tea as it is reported to reduce the absorption of iron from food.
  • Green tea is known to reduce blood sugar levels in the body. So, diabetic people on prescribed anti-diabetic medicines should refer to your doctor for determining the proper dosage of green tea for you.
  • Taking more than 2 cups of green tea flushes out calcium from your body thus leading to weaker bones. So, it’s advisable to take green tea in moderation.
  • While green tea is not considered unsafe during pregnancy, it is still a source of caffeine and should be consumed in moderation. So, if you are pregnant, it’s always advisable to talk to your doctor to know the right dosage of green tea for you.
  • Green tea is rich in caffeine, so, it’s better not to give it to children.

Green tea is considered safe to consume when taken as 1-2 cup a day. However, the exact dosage may vary depending on the individual body type, physiology and season. So, it's best to refer to a nutritionist before adding green tea in your health care regime.

Dt. Akanksha Mishra

Dt. Akanksha Mishra

Nutritionist
8 Years of Experience

Surbhi Singh

Surbhi Singh

Nutritionist
22 Years of Experience

Dr. Avtar Singh Kochar

Dr. Avtar Singh Kochar

Nutritionist
20 Years of Experience

Dr. priyamwada

Dr. priyamwada

Nutritionist
7 Years of Experience


Medicines / Products that contain Green tea

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