Green Tea: Benefits, Properties, and Contraindications

Tea is the second most consumed beverage in the world, after water. And it shouldn't be wasted. Especially if it's the magical green tea , which a long series of scientific studies now confirms as a natural remedy for various ailments and for various preventions. It improves metabolism and strengthens the immune system. It helps with weight loss, lowers cholesterol and triglycerides, and some studies consider it an ally in cancer prevention. It's also recommended for liver detoxification.

Index of topics

Property

Overall, there are over a thousand varieties of green tea, although they all actually come from the same plant, the green Camellia Sinensis . Subsequently, it is the processing that defines a specific variety: for example, for black tea, the leaves are fermented and therefore oxidized, while for green tea, the leaves are steamed immediately after harvest to prevent oxidation. This ensures that the green tea leaves retain all their beneficial properties intact. Other factors that make the difference, this time between the different types of green tea, are the soil, the climate, the period and the type of harvest. But one element above all unites all types of this beverage: green tea is a true panacea for the health and well-being of our body.

Green tea for cancer prevention

A study on green tea conducted by the Los Angeles Biomedical Research Institute and published in the scientific journal Metabolomics evaluated its effects on changes in tumor cell metabolism , particularly in slowing the growth of pancreatic cancer cells . Specifically, EGCG (epigallocatechin 3-gallate), the most important polyphenol in green tea, appears to alter the metabolism of pancreatic tumor cells by "suppressing" an enzyme associated with the tumor. This inhibitor, oxamate, is capable of reducing the activity of the LDHA (lactic acid dehydrogenase) enzyme, which is associated with the tumor.

Green tea for diabetes prevention

And that's not all: green tea also plays an important role in preventing other diseases, such as diabetes. A large-scale study conducted in Japan on over 83 individuals and published in the journal Stroke – Journal of the American Heart Association found that regularly drinking coffee or green tea reduces the risk of stroke by 20–30 percent.

Green tea to protect teeth

Furthermore, green tea helps control blood cholesterol levels, regulates blood sugar levels, prevents tooth decay and tooth loss thanks to its ability to counteract the action of one of the bacteria present in the oral cavity, and also promotes weight loss: catechins are thought to increase the rate at which the body burns excess fat.

Does green tea help you lose weight?

If your goal in using green tea is also to lose weight , be careful of two things. First, simply steep two tablespoons of tea in water that's not boiling but between 85 and 90 degrees Celsius. So, don't overdo it. Second, you can drink green tea, which aids diuresis, even cold; it doesn't need to be boiling hot.

Green tea and the hormone GLP-1

Although the belief that green tea helps you lose weight is spreading on social media, including through TikTok videos, it's important to remember that there's no scientific evidence to support this. According to some researchers, green tea promotes the production of the hormone Gip-1 after meals, which promotes insulin secretion, lowers blood sugar levels, and helps to regulate blood sugar levels. glycemia, slows gastric emptying and alters the activity of neurons that control hunger. But all this doesn't necessarily translate into weight loss. Despite the widespread belief on social media, including through TikTok videos, that green tea helps you lose weight, it's important to remember that there's no scientific evidence on this. According to some researchers, green tea promotes the production of the hormone GIP-1 after meals, which promotes insulin secretion, lowers blood sugar, and reduces blood sugar. glycemia, slows gastric emptying and alters the activity of neurons that control hunger. But all this doesn't necessarily translate into weight loss. The latest study published in Plose, examining the relationship between the hormone GLP-1 and green tea, concludes that this beverage does not increase its production, making it difficult to hypothesize a direct weight loss effect for those who drink black tea. Rather, a meta-analysis published in Nutrition Bulletin shows that, thanks to the significant presence of polyphenols, green tea can stimulate better fat absorption by the intestine, which may indirectly lead to weight loss.

Green tea and tanning

And according to some studies, catechins may also protect the skin from UV rays: another good reason to enjoy a cup of green tea even during the summer. This way, you can tan without overdoing it, knowing your skin is benefiting from natural protection.

Nutritional values

For every 100 grams of green tea there are 108 calories and the following nutritional values:

9,3 grams of water
2,0 grams of lipids
2,16 grams of potassium
19,6 grams of protein
630 mg of phosphorus
45 mg sodium
30 mg of calcium
15,2 mg of iron

Benefits

Native to northern India and southern China, rich in vitamins, minerals, polyphenols, and flavonoids—powerful antioxidants—green tea has been the focus of numerous scientific studies for years for its effectiveness in preventing cardiovascular disease and certain forms of cancer. Perfect as a hot beverage in the winter or iced in the summer, with a strong, pleasant flavor, green tea is obtained from dried leaves that are then heat-treated to prevent fermentation. This process prevents the oxidation of fermentation and allows the tea leaves to retain a large amount of healthy substances with antioxidant, anti-inflammatory, and anticarcinogenic properties. The main benefits of green tea are:

It is one of the best natural allies of the immune system
It has a natural laxative effect
It allows the body to burn more calories
It is an ally of the immune system
Thanks to catechins it reduces cholesterol and triglycerides
Thanks to antioxidants it reduces the risk of cardiovascular diseases

Variety

Among the different varieties of green tea , the following stand out in particular:

Sencha: the most common one, which we also find in sachets, with a very delicate flavour.
bench: with a stronger flavor, a macrobiotic medicinal food, with a low caffeine content.
Gyokuro: very precious Japanese tea, excellent to enjoy cold during the summer.

How much green tea can you drink per day?

Having clarified all the benefits of green tea, try not to overdo it with the number of times you drink it throughout the day. And limit your consumption to once or twice a day. Under certain circumstances, three times a day at most. Hot or cold makes no difference. Green tea, thanks to its mineral content, is also very useful in summer for compensating for water and salt losses. Instead, drink green tea in the morning or throughout the day, avoiding the evening, when the caffeine could overexcite the body and disrupt your regular sleep.

Controindicazioni

There are no particular contraindications for green tea , which is also readily available. However, there are two factors to keep in mind. The first concerns its significant caffeine content: therefore, it is not recommended to drink it in the evening, nor to give it to children. Furthermore, it is important not to overdo the dosage to avoid stress, anxiety, and insomnia. Secondly, the high concentration of polyphenols , according to recent studies, could lead to oxidative stress or liver toxicity: further good reasons to avoid excessive consumption and quantities. Finally, green tea can affect thyroid function.

Green tea: benefits, properties, and contraindications