Amounts of caffeine vary between teas, with black tea containing the most caffeine. Green and white teas contain the least, except for noncaffeinated teas.
Tea is one of the
The more tea leaves oxidize, the darker they become, which determines the type of tea:
- Black tea leaves are bruised, wilted, rolled, and completely oxidized.
- Green tea leaves are not wilted and are not oxidized.
- Oolong tea leaves are bruised, wilted, and partially oxidized.
- White tea consists of young leaves that are minimally oxidized.
Black tea is the most popular in the United States and Europe and accounts for about
In this article, we look at the most caffeinated teas, top healthy teas with no caffeine, and some of the risks involved in consuming too much caffeine.
The most caffeinated teas are black and oolong teas, with decaffeinated and herbal teas containing very little to trace amounts of caffeine.
Many teas offer various health benefits, as they contain:
- Antioxidants: These delay or prevent oxidative damage, which helps lower the risk of diseases such as heart disease and cancer.
- Phytochemicals: These plant compounds occur naturally. They may boost the immune system and play a role in lowering the risk of cancer and heart disease.
- Flavonoids: These are a type of polyphenolic phytochemicals and are also antioxidants.
- Flavonols: These are a type of flavonoids in tea that are powerful antioxidants.
- Epigallocatechin gallate (EGCG): This is a catechin in black and green teas and a powerful antioxidant.
- Theanine: This is an amino acid that may help reduce stress.
Black contains the highest amount of caffeine, ranging between 64 and 112 milligrams (mg) per 8-fluid ounce (fl oz) serving.
- Increased mental alertness: A person may feel more alert and pay better attention if they drink black tea throughout the day due to its caffeine content.
- Heart attack: People who drink black tea may be at lower risk of heart attack, while those who have been drinking black tea for at least 1 year may be less likely to die after having a heart attack.
- Low blood pressure: Caffeinated beverages may help increase blood pressure in older adults who experience low blood pressure after eating.
- Ovarian cancer: People who regularly drink tea seem to be at a
lower riskof developing this type of cancer than those who never or rarely drink tea.
Oolong tea contains between 29 and 53 mg of caffeine per 8-fl oz serving.
It contains no fats, sugars, protein, or fiber. Per
- 1 calorie
- 1 mg calcium
- 1 mg magnesium
- 1 mg phosphorous
- 12 mg potassium K
- 3 mg sodium
- 0.01 mg zinc
- 0.06 mg niacin
- 2 mg theobromine
Oolong tea may help with weight loss.
It may also help with heart disease, as research shows that oolong tea may lower cholesterol, which can lower the risk of heart disease.
The caffeine in green tea ranges between 24 and 39 mg per 8-fl oz serving.
According to the
- 1 calorie
- 0.22 g protein
- 0.02 mg iron
- 1 mg magnesium
- 8 mg potassium K
- 1 mg sodium
- 0.01 mg zinc
Green tea may have health benefits, including:
- Anti-carcinogenic properties for skin cancer: Human, in vivo, and in vitro
researchhas found that green tea may help in the chemoprevention of UVB-induced skin cancer. This could be due to the tea’s polyphenols, micronutrients found in plants.
- Inflammatory skin conditions:
Studieshave found that green tea and the EGCG it contains appear to help reduce inflammation.
- Cognitive ability:
Observational studiessuggest a link between green tea and a decreased risk of cognitive impairment.
The caffeine in white tea ranges between 32 and 37 mg per 8-fl oz serving.
- heart health
- protecting against the effects of harmful UV rays
- reducing inflammation
- weight loss
- improving cognitive ability
These contain less than 12 mg of caffeine per 8-fl oz serving, and many natural herbal teas that are caffeine-free contain no traceable amount of caffeine.
Many teas have zero to trace amounts of caffeine. A person can usually find a decaffeinated version of their favorite black, green, or white tea, including Earl Grey tea, but many herbal teas are naturally caffeine-free. Healthy caffeine-free teas with notable health benefits include the below.
This tea contains no caffeine. Research on animals suggests that rooibos supplements may help protect the liver from oxidative stress and may help lower blood pressure.
Consuming too much caffeine can cause health problems. The Food and Drug Administration (FDA) has cited
- increased heart rate
Some people should avoid or limit their intake of caffeine, including individuals who:
- are pregnant or breastfeeding
- have sleep disorders
- have high blood pressure
- have ulcers or gastroesophageal reflux disease
- have anxiety
- have migraine attacks
- take some medications, such as stimulants
Learn more about the potential risks and dangers of caffeine consumption.
The most caffeinated teas include black, oolong, green, and white teas. These all have potential health benefits, as they contain antioxidants, polyphenols, flavonoids, flavonols, and other health-promoting compounds.
Health benefits of tea include:
- cardiovascular health due to lower cholesterol
- weight loss
- antioxidant protection
- protection from the effects of harmful UV rays
- reduced inflammation
If a person wishes to avoid caffeine, which may overstimulate or interact with certain health conditions, decaffeinated varieties of popular teas are usually available. Some teas, including many herbal teas, are naturally caffeine-free. Healthy caffeine-free teas with health benefits include rooibos, hibiscus, and chamomile tea.