Tea, a source of antioxidant properties¹

Tea has been regarded as a social drink for centuries. Since tea was first discovered, there have been many theories about its potential health benefits. However, it was not until around 40 years ago that the properties of tea were scientifically researched.

Tea is the second most-consumed beverage in the world, after water and ahead of coffee. It is consumed by two-thirds of the world’s population².  

Tea is a popular social drink due to its xanthic base content. This includes theine, a name given to the caffeine that occurs in tea.

Benefits and properties

Camellia sinensis, also known as the tea plant, has beneficial antioxidant properties for health. It is a confirmed source of antioxidants³. Drinking tea therefore helps to strengthen the body’s antioxidant defences¹. 

Antioxidants help protect our body by strengthening its natural defences against the harmful effects of free radicals⁴. This action helps to reduce cell ageing due to oxidative damage⁴.

Tea contains theanine, which promotes a state of relaxation and rest and calms the mind⁵. It also has other benefits, such as helping to control weight⁶ and its diuretic effect⁷.

Consuming tea also supports the immune system⁸, contributes to the body’s natural defences⁸ and helps maintain to heart health. It also helps maintain healthy glucose levels¹⁰, regulate the LDL/HDL ratio and blood cholesterol levels¹¹ and improve blood flow¹².

Tea enhances cognitive function by helping to refresh the body and mind¹³, helping to keep the body alert. 

Tea is also beneficial for the digestive system. Regular tea consumption helps maintain a healthy digestive system¹⁴, improving intestinal functionality¹⁴. In addition, drinking tea after taking antibiotics helps to enhance beneficial bacteria¹⁵. Drinking tea therefore maintains healthy intestinal flora¹⁴. 

Tea as an antioxidant

Many scientific studies have been carried out to investigate the increase in antioxidant capacity in our body from drinking green tea. This research points to the importance of tea as a potent antioxidant, due to its flavonoids (a type of polyphenolic compound).

Flavonoids are natural pigments present in plants. These pigments have antioxidant capacity and are absorbed through the gut after drinking tea¹⁶.

The antioxidant power of tea slows down cell ageing caused by oxidative damage⁴, because it helps protect our body by strengthening its natural defences against the harmful effects of free radicals⁴.

Which is the most antioxidant tea?

Tea is made from the dried leaves or shoots of the Camellia sinensis (L.) Kuntze plant, part of the Theaceae family. Once ground, its leaves are mixed with hot water and used as a drink.

Research shows that the types of tea found to have the greatest antioxidant capacity are green tea and black tea⁵. This is because tea consumption contributes to healthy ageing by keeping cellular DNA intact¹⁷.

Types of tea

There are different types or classes of tea depending on the time of harvesting. 

Green tea

Green tea is created from leaves that are stabilised with pressurised water vapour after harvesting. This method prevents enzymatic oxidation¹⁸. The quality of green tea depends mainly on the time of harvest and the age of the leaves⁶. The main components of green tea are polyphenols (~ 90%), amino acids (~ 7%), theanine, proanthocyanidins and caffeine (~ 3%)¹¹. 

Immediately after harvesting, the leaves are then rapidly dried by heating or steaming. This prevents fermentation and ensures its chemical composition is barely altered.

Green tea offers a wide range of beneficial properties for the human body. Among them is its contribution to the oxidation of fats¹⁹. This is because when green tea is combined with a healthy diet and exercise, it can help with weight control²⁰, increase fat oxidation and reduce body fat²⁰. Natural green tea extract also helps to improve metabolism²¹.

In addition, several in vivo and in vitro studies have investigated the effects of green tea on photoaging. Photoaging is the skin ageing process caused by exposure to ultraviolet (UV) light²². 

One study was conducted where the effect of green tea on the consequences of photoaging was observed. It was found that in those who were given green tea extract, the level of collagen and elastin fibres increased, while the expression of MMP-3 enzymes (which degrade collagen) was reduced, indicating anti-wrinkle effects²³. Green tea therefore helps to protect the skin against UV-induced oxidative damage²². 

The European Medicines Agency has approved the use of green tea leaf for relieving fatigue or feelings of weakness²⁴.

Matcha tea

Matcha tea is a type of green tea of Japanese origin. It is considered a tea with high antioxidant potency²⁵. Factors such as time of harvest and the temperature at which the water used for brewing the infusion is brewed influence its characteristics¹³. Matcha is the Japanese green tea powder that has achieved great popularity thanks to its antioxidant capacity¹³.

Research suggests that three components present in matcha tea (l-theanine, epigallocatechin gallate (EGCG) and caffeine) could affect mood and cognitive performance²⁶. 

Matcha tea-based infusions, particularly from the second and third harvests, can also be a valuable source of antioxidants¹.

Black tea

Black tea differs from other types of tea because its fermentation process is complete. 

Drinking black tea is an excellent option if you are looking for an alternative to coffee or energy drinks, as it is one of the most caffeinated teas²⁷. 

Tea consumption helps to strengthen the body’s antioxidant defences, which in turn help protect the body by strengthening its natural defences against the harmful effects of free radicals¹.

Red tea

Red tea, also known as ‘Pu-erh’ tea, is obtained after a brief drying process, first outdoors, then in an enclosed place. The fermentation of its leaves can take from 2 to 60 years in bamboo barrels. 

Studies show that consuming red tea could be effective in lowering lipid peroxidation levels²⁸. This is due to the antioxidant properties of tea³, meaning there is less free radical action on the lipids that make up the cell membrane.

Research has focused on red tea’s ability to exert action on fats, particularly those that build up in the liver²⁹. 

Tea is seen to help control fat metabolism³⁰, prevent fat accumulation³⁰, and also help maintain healthy blood glucose levels³¹ and protect insulin-producing glands³².

With increased storage time, the concentration of lovastatin in Pu-erh tea increases significantly³³.

White tea

White tea is made from the leaves and young shoots of the plant, dried in the sun and processed to prevent oxidation. It is harvested before the tea flower opens, which is why white tea is also known as ‘tea buds’. 

One the benefits of tea is that it is considered as source of antioxidants (1). As a result, drinking white tea helps to improve the body's antioxidant defences¹. 

A recent study has shown that prolonged white tea intake may protect us from oxidative stress³⁴ due to the antioxidant properties of tea¹. Other research shows that daily consumption of white tea could improve glucose tolerance and insulin sensitivity³¹. This is because it helps prevent the build-up of fats³⁰, and also helps to maintain healthy blood glucose levels and protect insulin-producing glands³².

Oolong tea or blue tea

Oolong tea has been a popular drink worldwide due to its health characteristics, which include beneficial antioxidant properties³⁵ and which promote energy expenditure and fat oxidation³⁶.  

The polysaccharides, caffeine and polyphenols in oolong tea contribute to its health characteristics³⁷. Research has reported that ingesting oolong tea extract significantly increased energy expenditure in a group of young people³⁸. 

Since then, clinical trials have pointed to tea preparations contributing to increased energy expenditure, fat oxidation, weight loss, reduced fat mass and weight maintenance after weight loss⁶.

Which type of tea is better? 

Scientific research indicates that green tea has the most health benefits. The greater benefits of green tea in comparison with others stem from green tea’s production process³⁹. 

The process of making green tea barely alters its chemical composition, as the leaves are stabilised to avoid enzymatic oxidation.

The process helps the tea retain its catechin content. In addition, not fermenting it in the sun allows it to return a greater number of polyphenols. 

When to drink tea?

Many people ask if it is advisable to drink tea on a daily basis, and the answer is yes. The European Medicines Agency (EMA) indicates and approves the traditional use of tea⁴⁰. This is because green tea leaves contain xanthic bases such as caffeine (theine) and theobromine, saponins and polyphenols. 

The EMA states that for adults, herbal tea infusions of 1.8 to 2.2 g should be consumed 3 to 5 times a day with 100-250 ml of boiling water⁴¹.

Tea contains catechins, molecules that are considered antioxidants. Due to the different antioxidant components making up tea, it is considered a source of antioxidants¹. It contributes to the oxidation of fats⁴² and helps to maintain weight¹¹.

In addition, its antioxidant components (polyphenols) are what give it its various properties – protecting the body against the harmful action of oxidizing substances and free radicals that weaken its natural defence system¹. 

Tea contraindications

Tea contains thiaminases, enzymes that destroy thiamine⁴³. People who regularly drink tea may therefore become deficient in this important vitamin for the nervous system.

However, it should be remembered that if tea contains caffeine, it is not recommended for people with medical conditions⁴⁴. 

Excessive consumption of green tea also has the disadvantage of hindering the absorption of iron found in food. Consuming it would not therefore be recommended for those experiencing anaemia⁴⁵.

How to consume tea?

Anastore offers you various ways of enjoying this product.

• Green Tea extract capsules, standardised to contain 50% polyphenols, making them a potent source of antioxidants (1). Their high EGCG (epigallocatechin gallate) content guarantees Anastore’s green tea the highest possible quality.
• You can also explore our range of teas and infusions. We offer a wide range of organically grown aromatic, delicious teas. 

Green tea

400 mg / 60 capsules

22,00 €

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Organic Jasmine Jinjing green tea

Jasmine Jinjing green tea 70 g

16,00 €

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Organic matcha green tea

Matcha green tea 50 g

16,00 €

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Organic Sencha green tea

Sencha green tea 70 g

16,00 €

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