Possibly the healthiest beverage on this earth, green tea is one of the most consumed teas.
Green tea, in particular, is produced without fermenting and oxidizing the leaves. To prevent oxidation, the leaves are steamed (Japanese style) and fried (Chinese style).
Enriched with unimaginable range of benefits, green tea’s consumption is increasing significantly and the statistical data have shown that growth of green tea has increased by 60% over a decade.
Nutritional value of green tea
Approximately 2.5 million metric tons of dehydrated tea is manufactured around the world in a year. And, out of this only 20% is green tea.
What makes green tea different and healthier than other beverages?
The leaves of green tea are minimally oxidized or not oxidized at all. As a result, unmatched level of nutrients are present in it.
Ingredients Fact Sheet
Quantity: 1 Mug [8 fl. Oz.]
Caffeine: 24 - 45 mg
|Ingredients||Quantity||Average Intake||Daily Value %|
|Protein||0.47 g||51000 mg||0.92 %|
|Sugar||0 g||30000 mg||0 %|
|Sodium||7 mg||2300 mg||0.3 %|
|Potassium||63 mg||4700 mg||1.34 %|
|Calcium||7 mg||1000 mg||0.7 %|
|Magnesium||4 mg||350 mg||1.14 %|
|Phosphorus||4.7 mg||1000 mg||0.47 %|
|Iron||0.45 mg||15 mg||3 %|
|Copper||0.02 mg||1.5 mg||1.33 %|
|Fluoride||2.36 mg||3.5 mg||67.43 %|
|Manganese||0.72 mg||5 mg||14.4 %|
|Vitamin B2||0.11 mg||1.3 mg||8.46 %|
|Vitamin B6||0.02 mg||15 mg||0.13 %|
|Vitamin C||14 mg||75 mg||18.67 %|
|Folate||0.03 mg||0.4 mg||7.5 %|
|Dietary Fiber||0 g||30000 mg||0|
|Cholesterol||0 mg||250 mg||0|
|Total Fat||0 mg||61000 mg||0|
|Total Carbohydrate||0.47 g||300000 mg||0|
Amount of Polyphenols found in a cup of green tea
|Amount||2 - 3%||4 - 6%||5 - 9.5%|
Reckoned as more than just a tea, green tea comes with a package of benefits, a reason that has made it popular worldwide.
Health Benefits of Green Tea
From treatment of simple medical conditions like bacterial infection to helping fight cancer and preventing heart diseases, green tea has large number of benefits. Thanks to the vital bioactive compounds present in this super beverage.
Lowers risk of cancer
Cancer is triggered by unnecessary growth of cells in the body.
Green tea has special component called catechin which helps to kill cancer cells, without any harm to healthy tissues. Furthermore, the polyphenol, a powerful antioxidant helps in stopping the development of cancer due to oxidative stress (inability of body to detoxify free radical damage through neutralization by antioxidants). Learn more on - green tea and cancer prevention
Researches on green tea
- A meta-analysis of observational studies found that chances of developing breast cancer, the most common cancer in women, reduced by 22% in women who drank green tea regularly. 
- A placebo controlled study conducted on 97 men found that risk of prostate cancer was reduced in Polyphenol E group as compared to the placebo group. 
- A study conducted on 69,710 Chinese women found that chances of colorectal cancer was significantly lower in those who drank green tea regularly compared to non-drinkers or occasional drinkers. 
- A study conducted in South China on women with ovarian cancer concluded that women who drank at least a cup of green tea everyday lived longer than those who did not. In fact, women who drank the most tea had the longest life with disease. 
- A research was conducted to evaluate the effect of tea extracts on precancerous (likely to develop into cancer if not treated timely) oral lesions. 59 people with leukoplakia were involved in the research, some of whom were given 3 grams of mixed tea product while the others were given a placebo.
At the end of the 6 month trial, it was found that 38% of participants in tea product group experienced regression of their oral lesions while only 10% participants experienced positive effect in placebo group. Similarly, only 3% of participants in tea product group had an increased lesion compared with 7% in the placebo group.
Another study was conducted on a group of 39 people with high-risk precancerous oral lesions. The participants were given three different doses of green tea extract and placebo for 12 weeks. But no differences were found in the participants after the trial ended. 
- Research conducted on laboratory animal have proved that polyphenols in green tea halt the growth of esophageal cancer. However, no particular conclusion have been drawn from studies on humans.
A study conducted on mass population found that drinking green tea offered protection against development of this cancer in women while another research resulted just the opposite.The contrasting research also stated that the risk of esophageal cancer was greater in drinkers and smokers who drank hotter and stronger green tea. [6, 7]
Further studies are necessary before scientists draw any conclusion regarding green tea for esophageal cancer.
- Green tea’s effect on lung cancer is still a debate between researchers.
Some research have shown that risk of lung cancer may be reduced with high consumption of green tea. Other research have noted no evidence on link between green tea and lung cancer. [8, 9]
- Laboratory studies have found that polyphenols in green tea are capable of inhibiting the growth of stomach cancer cells in test tubes. However, studies on mass population have not succeeded to make any conclusions. 
Reduces risk of heart diseases
Flavonoids found in green tea helps in dilation of blood vessels, helping in regular flow of blood through it. As a result, cardiovascular diseases including high blood pressure and stroke are prevented. 
Several anti-allergenic components are found in green tea. And, among them methylated epigallocatechin gallate (EGCG) has been recognized to be the most potent which is abundant in green tea than in other processed teas such as black and oolong.
Immunoglobulin E (IgE) and histamine are the two most active components that trigger allergy. The normal EGCG blocks the production of these components while the methylated EGCG can block the IgE receptor, the receptor involved in allergic response. 
Lowers Risk of Diabetes
Type II Diabetes is caused when our body becomes resistant to insulin's effect or fails to produce enough insulin and blood sugar level elevates. And recent data have shown that more than 300 million people worldwide (about 80%-90% of all diabetics) are afflicted by this disease at present.
According to a study published by Annals of Internal Medicine, people who consumed 3-6 cups of green tea or coffee had 33% lesser chances of getting Type II Diabetes. The inverse case were more pronounced in women and obesed men. 
Improves brain function
Green tea is also a caffeinated drink. Although caffeine in green tea is significantly lesser than that in other tea and coffee, it has ability to not just wake you up but to keep you alert and focused.
It is because caffeine in green tea is accompanied by L-theanine. It is an amino acid having anti-anxiety effects which lowers stress level and provides relaxing effect. 
Overall, the combination of caffeine and L-theanine works synergistically to improve mood, focus and alertness of mind.
Lowers risk of dementia
Caffeine does not only help in improving brain function but prevents dementia as well. Dementia is a term used to define chronic mental deterioration marked by issues such as memory disorder, change in personality, etc. In general, caffeine prevents neurodegenerative diseases such as Alzheimer’s and Parkinson’s. [15, 16]
Improves physical performance and boosts endurance
Green tea, which is rich in antioxidants, adds to thermogenesis by 4%. Thermogenesis is a process of burning calories while absorbing food and digesting. In addition, polyphenols burn fats that are accumulated in body cells and helps in losing weight.
Overall, drinking green tea helps in increasing rate of energy expenditure. Drink green tea at least half an hour before working out or doing any work, and feel the difference in your energy level. 
Researchers have noted that catechin help to protect tissues of eyes and prevent various eye diseases including glaucoma. Studies have shown that antioxidant activities occur in various parts of eyes which absorb catechin and these activities last for roughly 20 hours. 
Green tea has such compounds which cause contraction in tissues.
Drinking green tea or just using it as a mouthwash create sufficient contraction in gums and helps to prevent gingival bleeding. 
In the same way, washing your scalp with green tea water prevents hair fall and cleansing your skin with cool green tea reduces fine lines and sagginess.
Beauty Benefits of Green Tea
Drinking green tea has several benefits on our health. But it’s not the end. It has also potential to keep you beautiful by acting upon your skin and hair.
To get benefits from green tea for beautiful skin, you can either drink it or use it externally as lotion or face pack. Green tea is known to have following skin benefits.
- Antioxidants in green tea can remove different kinds of toxins, scars, blemishes and inflammation from your skin, leaving it fair and naturally glowing.
- Green tea contains numerous antioxidants, and epigallocatechin gallate (EGCG) is one of the most abundantly present antioxidant. EGCG along with other polyphenols offer protection to skin from possible sun damages induced by harmful UV rays. 
- Application of green tea extract on skin can reduce production of excessive oil. 
- Free radicals in skin are the major reason behind signs of aging such as wrinkles, spots, fine lines, sagging skin, etc. Polyphenols like EGCG present in green tea wipes off these free radicals and rejuvenates dying skin cell, leaving you with younger looking healthy skin. 
- Tannins and antioxidants in green tea can help eliminating dark circles and puffy eyes.
- Green tea can be as effective as antibiotic skin creams in treating acne. 
- Using green tea as scrub helps in exfoliating your skin.
- Applying green tea topically is effective on healing process of second degree burn wounds.
Therefore, using green tea after shave might help in reducing the burning sensation. 
- Green tea is a natural treatment to cleanse impurities, reduce open pores and keep skin hydrated. Simply, it tones your skin.
- Using green tea extract for bathing can reduce the effect of atopic dermatitis. 
Whether you want to mend your deteriorating hair quality or keep it hydrated and frizz-free, green tea can do it all. Major benefits of green tea on hair include
- Epigallocatechin Gallate (EGCG) and other polyphenols in green tea have potential to halt hair fall and promote hair growth. 
- Using green tea shampoo can help you in getting rid of dandruff and psoriasis.
- Vitamin, panthenol and other nutrients in green tea helps to reduce spilt ends.
Drink Green Tea with Caution
Nowadays, green tea is so popular that very few people are aware of its possible negative effects on our health. Regarded as a natural medicinal drink, green tea can harm us to an unimaginable extent if consumed in an inappropriate amount.
- Drinking green tea in an empty stomach may increase possibility of liver damage. 
- Drinking excessive green tea may cause anxiety, insomnia, dizziness and even depression in less tolerant people as a consequence of high caffeine level in body. 
- Do not drink green tea if you are under any medication. Or at least consult your doctor to avoid any consequences.
- Green tea is not considered pregnancy friendly as it can cause neural tube birth defect. 
- Green tea is a calorie-free drink and is considered the best pick to help you in losing weight. However, adding milk, sugar and other calorie rich substances may give you adverse result.
More cups of green tea in a day means more amount of caffeine, polyphenols, tannins and all other bioactive compounds. From the above points, you must have figured out how harmful can these compounds be if consumed in an inappropriate amount.
Some experts may argue that 5 cups of green tea per day is good for our health while some others may suggest 3 cups in a day.
So which suggestion should you look up to?
3 cups of green tea is more than enough for you to receive maximum benefits from it. However, if you would like to have more green tea, never exceed 5 cups in a day.