Green tea is one of the oldest drinks in the world and its properties have made it popular in natural medicine. It comes from the leaves of the Camellia sinensis plant and is beneficial in preventing heart disease, some types of cancer, and different viruses. Its properties also increase mental agility and lower cholesterol.
Camellia sinensis L., the plant from which green and black tea are derived, belongs to the Theaceae or Ternstroemiaceae family and is native to northern India and southern China. It is a perennial, branched shrub that reaches a height of approximately 10 meters.
According to Ma. Tránsito López Luengo, a pharmacist, in the text Green Tea, in the scientific journal Fitoterapia in Elsevier, that the green tea plant was accidentally discovered by an emperor more than 4,000 years ago in China. Since then, it has remained one of the preferred and most medicinal drinks in Asian countries.
The importance attributed to green tea concerning its medicinal properties compared to other teas lies in its preparation process. To prepare it, immediately after harvesting the leaves, they undergo a rapid drying process by steam or heating.
The processes hardly alter its chemical composition, since the green tea leaves are stabilized and their enzymatic oxidation is avoided, says López Luengo.
Properties of green tea
Green tea can be drunk as an infusion or taken in tablet or capsule form. It contains high amounts of flavonoids, polyphenols, and catechins, antioxidant substances that help protect the body’s cells that could be damaged by mutations or cancer, explains Eduardo Solís, a naturopath.
This drink, when taken without sugar, contains no calories, no proteins, no fats, and no carbohydrates. In addition, it is rich in vitamins A, C, and E, as well as some B vitamins. It contains manganese, fluoride, zinc, and copper, in small quantities.
Benefits of green tea
“Green tea is popular because scientific studies have shown that it works to prevent cancer and cardiovascular diseases such as coronary artery disease, which is when the blood supply to the myocardium is partially or completely blocked,” says Anaite Gutiérrez, nutritionist.
It is also used to reduce blood lipid levels, relieve pain due to osteoarthritis and symptoms of menopause, lose weight, preserve memory, and enhance longevity.
These are some of the benefits of constant consumption of green tea:
- Prevents some types of cancer: because it contains concentrations of ECGC, a catechin that constitutes the bioactive component of this plant and is a powerful antioxidant.
- Protects against heart disease: Constant consumption of this drink makes a person less likely to suffer a stroke and reduces high blood pressure, as well as cholesterol and triglycerides.
- Improves brain function: Green tea contains caffeine, less than coffee, but it helps produce a positive response from the brain. It increases the activation of neurons and the concentration of neurotransmitters, such as dopamine and norepinephrine.
- Reduces fat and improves physical performance: this is why it is said to help you lose weight because it boosts your metabolic rate and helps you burn fat. However, it needs to be accompanied by a good diet and constant exercise.
- Prevents Alzheimer’s and Parkinson’s: Constant consumption of green tea helps protect the brain from aging, thus helping to prevent degenerative diseases such as Alzheimer’s and Parkinson’s. Catechin components may have a protective effect on neurons.
- Prevents some viruses and infections: The catechin components are said to help kill bacteria and viruses, such as influenza. This would help prevent infections. It also promotes oral health, since one of the most common bacteria that causes diseases in the mouth is Streptococcus.
Who should not consume green tea?
Experts say that although there is scientific evidence about the benefits of regular consumption of green tea, it should be avoided to drink too much of it. Ideally, you should not exceed five glasses a day, otherwise, it could cause side effects such as headaches, diarrhea, sleep disorders, dizziness, heartburn, and elevated heart rate.
It should also not be mixed with medications and excessive amounts of alcohol since green tea contains caffeine, which when mixed with other components could cause damage to the body.
Pregnant and breastfeeding women should consult their doctor about drinking green tea. Those who suffer from anxiety, glaucoma, heart problems, liver disease, and anemia should also consult a specialist first or refrain from drinking this beverage.