Caffeine amounts vary between teas, with black tea containing the most. Green and white teas contain less, with the exception of caffeine-free teas.
Tea is one of the most popular drinks in the world. It consists of the leaves of the Camellia sinensis plant which, after harvest, begin to wither and rust. The oxidation process can be stopped by heating the leaves.
The more the tea leaves oxidize, the darker they become, which determines the type of tea:
Black tea leaves are withered, rolled up and completely oxidized.
Green tea leaves do not wilt or oxidize.
Oolong tea leaves are withered and partially oxidized.
White tea is made up of young leaves that are very slightly oxidized.
Black tea is most popular in Europe and accounts for around 75% of global tea consumption. In Japan and China, green tea is the most popular. Oolong tea and white tea are the least consumed in the world.
The amount of caffeine in a tea varies depending on the type of tea. The most caffeinated teas are black and oolong teas, decaffeinated teas, and herbal teas that contain very little or trace amounts of caffeine.
Many teas offer various health benefits, as they contain:
Antioxidants: They delay or prevent oxidative damage, which helps reduce the risk of diseases such as heart and cancer.
Phytochemicals: These plant compounds occur naturally. They can boost the immune system and play a role in reducing the risk of cancer and heart disease.
Flavonoids: These are a type of phytochemical polyphenols and are also antioxidants.
Flavonols – These are a type of flavonoids found in tea that are powerful antioxidants.
Epigallocatechin Gallate (EGCG) – This is a catechin found in black and green teas and is a powerful antioxidant.
Theanine – This is an amino acid that can help reduce stress.
Black tea contains the most caffeine, between 64 and 112 milligrams (mg) per 200-g serving.
Black tea contains no calories, fat, protein, fiber, vitamins, or sugar. However, like other teas, it contains flavonoids, phytochemicals, flavonols, theanine, and antioxidant properties that promote health. Black tea can help:
Increase Mental Alertness: A person can feel more alert and more attentive if they drink black tea throughout the day due to its caffeine content.
Heart attack: People who drink black tea may have a lower risk of heart attack, while those who have been drinking black tea for at least a year may be less likely to die from a heart attack.
Low blood pressure: Caffeinated beverages may contribute to increased blood pressure in older people who experience low blood pressure after eating.
Ovarian cancer: People who drink tea regularly seem to have a lower risk of developing this type of cancer than those who never or rarely drink it.
Oolong tea contains between 29 and 53 mg of caffeine per 2.5 liter serving.
It does not contain fats, sugars, proteins or fibers. For every 100 grams (g), oolong tea has:
1 mg of phosphorus
12mg potassium K
Oolong tea can help with weight loss. Animal studies suggest that regular consumption of oolong tea and other types of tea may aid weight loss thanks to the antioxidant EGCG it contains. It may also help fight heart disease, as research shows that oolong tea can lower cholesterol, which can reduce the risk of heart disease.
The caffeine in green tea ranges from 24 to 39 mg per 200 g serving.
Per 100g, green tea is fat, sugar and fiber free and contains:
8 mg potassium K
Green tea may have health benefits, including
Anticancer Properties for Skin Cancer: Human, in vivo, and in vitro research has found that green tea may aid in the chemoprevention of UVB-induced skin cancer. This could be due to tea polyphenols, micronutrients found in plants.
Inflammatory skin conditions: Studies have found that green tea and the EGCG it contains appear to help reduce inflammation.
Cognitive abilities: Observational studies suggest a link between green tea and a reduced risk of cognitive decline.
The caffeine in white tea ranges from 32 to 37 mg per 200 g serving:
White tea is nutritionally similar to green tea and is less processed than black tea, Oolong tea, and green tea, meaning it retains more antioxidants. It has many of the same benefits as these other teas and can also help:
protection against the effects of harmful UV rays
improve cognitive skills
These teas contain less than 12 mg of caffeine per 8-ounce serving, and many natural caffeine-free herbal teas contain no trace of caffeine.
The best healthy teas without caffeine
Many teas do not contain a trace of caffeine. You can usually find a decaffeinated version of your favorite black, green, or white tea, including Earl Gray tea, but many herbal teas don’t naturally contain caffeine. Some non-caffeinated teas with notable health benefits include the following.
This tea does not contain caffeine. Animal research suggests that rooibos supplements may help protect the liver from oxidative stress and lower blood pressure.
Research suggests that hibiscus leaf extracts may offer antitumor and antioxidant properties and may support cardiovascular health and healthy blood pressure.
Chamomile tea can help improve sleep in people with insomnia. It can also lower cholesterol levels, improve cardiovascular health, and provide antioxidant protection.
Curcumin, found in turmeric and giving it its distinctive yellow color, improves immune function with antioxidant, anti-inflammatory, antiviral, and antibacterial properties.
The risks of caffeine
Excessive caffeine consumption can lead to health problems. The research cited 400 milligrams, or about 4 or 5 cups of coffee, as the maximum recommended amount per day. However, consuming more than this figure is linked to dangerous negative effects, including:
increased heart rate
Some people need to avoid or limit their caffeine intake, including people who:
are pregnant or breastfeeding
have trouble sleeping
have high blood pressure
have ulcers or gastroesophageal reflux disease
they are anxious
are taking medications, such as stimulants.
The most caffeinated teas are black tea, Oolong tea, green tea, and white tea. They all have potential health benefits because they contain antioxidants, polyphenols, flavonoids, flavonols, and other health-promoting compounds.
The health benefits of tea include:
– cardiovascular health thanks to the reduction of cholesterol
– protection against antioxidants
– protection against the effects of harmful UV rays
– reduction of inflammation
If a person wishes to avoid caffeine, which can cause overstimulation or interact with certain health conditions, decaffeinated varieties of popular teas are commonly available. Some teas, including many herbal teas, do not naturally contain caffeine. Some health-promoting caffeine-free teas include rooibos, hibiscus, and chamomile.
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