Does Black Tea Have Health Benefits?

After water, tea is the most popular drink in the world, with black tea being the most common variety in the United States and Western Europe.

But can drinking black tea improve your health? The short answer is yes, possibly. Recent research indicates that black tea may help lower blood pressure, improve gut health, and support cognitive function.

These potential effects may relate to black tea’s content of bioactive compounds like caffeine and polyphenols such as catechins and theaflavins. However, not all of these benefits have equally strong evidence behind them.

In this article, we’ll explain what the latest scientific findings show and interpret exactly what this means for black tea drinkers.

What is Black Tea?

There are four main varieties of “true” tea, which means tea made from the leaves of the Camellia sinensis plant. These are black, green, white, and oolong tea, and the differences between the four revolve around what happens to the leaves after picking.

How Is Black Tea Made?

The production process for black tea involves three primary stages after picking:

• Rolling and crushing: After picking, the producers roll and crush the green tea leaves, which releases liquids containing enzymes like polyphenol oxidase. This is the same enzyme that turns bananas brown, and it oxidizes the leaves, turning them into the dark color that we associate with black tea.
• Oxidation: After the rolling process, the tea leaves are left to oxidize in a temperature-controlled area. While the exact temperature will vary by producer, research shows successful oxidation at temperatures between 20–35°C (68–95°F).
• Drying: After the leaves reach the desired oxidation levels, they are heat-dried to stop further oxidation. A 2025 study found that the optimum temperature for this was 105°C (221°F).

In addition to changing the appearance of the leaves, this oxidation process changes the chemical composition of the tea leaves.

For example, black tea contains a significant amount of polyphenols called theaflavins while green tea does not. Polyphenols are bioactive compounds that have been extensively investigated for their potential health benefits.

Potential Health Benefits

In recent years, a range of research has attempted to ascertain whether black tea intake can provide health benefits.

We’ll now look at some of the main findings from these studies.

May Lower Blood Pressure

There has been a lot of research on how black tea may benefit blood pressure, including several systematic reviews.

• A 2021 systematic review of 13 trials found that black tea intake significantly reduced systolic and diastolic blood pressure.
• An earlier 2020 systematic review of 5 trials also found that black tea may lower blood pressure in people with elevated blood pressure. Notably, more significant effects were seen over longer periods, particularly when consumed for over 3 months. While black tea had these effects, green tea had a more significant impact.

However, a 2020 review of randomized controlled trials found that short-term (mean duration: 7.4 weeks) black tea intake didn’t have a significant effect on blood pressure.

Black Tea and Cholesterol Levels

Research has also looked into whether black tea intake can influence blood cholesterol levels, specifically LDL cholesterol (LDL-C). You may have heard LDL-C referred to as “bad cholesterol” because higher levels are thought to be a causal risk factor in developing cardiovascular disease.

An older 2015 systematic review of randomized controlled trials found that black tea intake led to “significant” reductions in LDL-C. This reduction was by 4.64 mg/dL.

However, a more recent 2019 systematic review analyzed seven studies where black tea was given to people with high cholesterol levels. Compared to placebo, black tea had no significant effect on LDL-C levels.

The authors of the 2019 study noted that it was difficult to be certain of the results due to the “low quality” of the existing studies.

While the evidence here is mixed and further research may change that, the existing data does not firmly support black tea having any benefits for LDL-C. The reasons for conflicting findings in the studies may be numerous, ranging from the study durations, health status of participants, and more.

May Support Gut Health

After previous research suggested black tea intake reduced the risk of respiratory tract inflammation, a 2023 study involving 72 participants investigated whether the tea had an impact on the gut microbiota.

The researchers investigated this because initial research has indicated there may be a link between gut health and respiratory conditions.

In the study, consuming three cups of black tea per day led to changes in the gut microbiota. Notably, these changes included a microbiota composition with a higher abundance of bacteria with roles in immune function.

While it is only one small study and more research is necessary, previous research has indicated that the polyphenols in black tea may be able to change the types of bacteria in the gut.

May Support Healthy Blood Flow

An older 2009 trial found that black tea may support better circulation.

In the study, which was a randomized controlled crossover trial, 19 healthy men consumed various black tea intakes, ranging from 0 to 800 mg. Interestingly, the results indicated that:

• Flow-mediated dilation improvement: Consuming 100 mg of black tea, which is less than one typical cup, improved flow-mediated dilation (FMD). FMD refers to how healthy the blood vessels are, and if they relax and widen as they should.
• Higher doses were more effective: Increasing black tea intake to 800 mg per day led to further significant improvements in FMD compared to 100 mg per day.

Notably, this trial also found what other studies have; black tea intake slightly decreased systolic and diastolic blood pressure.

While this was only a small study, further research in the area appears to support its findings:

• Tea intake improves FMD: A 2011 meta-analysis of 9 studies found that tea in general (whether green or black) improves FMD. This analysis found that drinking just 2–3 cups per day improved how well arteries could widen by about 40% compared to a placebo.
• Catechin supplementation improves FMD: A 2019 systematic review found that catechin supplementation significantly increased FMD. Catechins are among the flavonoid polyphenols that black tea contains.

May Support Age-Related Cognition

A 2024 systematic review found evidence suggesting tea may have a beneficial impact on age-related cognitive function, which means how memory and thinking skills change in older adults.

The review also found an association between black tea intake and a reduced risk of developing cognitive disorders in Eastern countries.

However, it is important to note that the authors rated the quality of the evidence they had as “generally low to moderate.” This means that further, stronger evidence is necessary to confirm these findings.

That said, mechanistic studies have indicated that theaflavins in black tea may influence age-related cognition. For instance, a 2023 animal study found that black tea theaflavins changed the composition of gut bacteria in mice to a composition thought to better support gut-brain communication, immune function, and behavioral improvements.

Still, further research is necessary before any strong conclusions can be made.

Can Black Tea’s Caffeine Content Provide Benefits?

A cup of black tea typically provides around 47 mg of caffeine, which is approximately half as much as a cup of coffee.

Extensive research has linked caffeine to a variety of potential benefits for sports performance. However, the International Society of Sports Nutrition states that an effective dose of caffeine for sports performance is 3–6 mg per kg of bodyweight.

In other words, it is unlikely that a cup or two of black tea (50–100 mg) would provide these benefits for the average adult.

That said, a 2017 randomized controlled trial found that caffeine doses as low as 60 mg led to significant improvements in attention and alertness. This data suggests that 1–2 cups of black tea may help support attention.

Does Black Tea Have Any Drawbacks?

While black tea is generally considered to be a healthy drink, it may have some potential downsides.

May Lower Iron Absorption

Research has shown that polyphenols in black tea appear to lower the absorption rate of non-heme iron. This happens due to tannins binding with non-heme iron in the gut, thus limiting its absorption.

Non-heme iron is the type of iron found in plant-based foods like beans and leafy greens.

Research in the area indicates:

• Anemia risk: Habitual tea drinking may increase the risk of anemia, according to a 2022 systematic review. In this study, pregnant women who drank tea had 1.94 times the risk of anemia compared to women who didn’t drink tea.
• Black tea has a strong inhibitory effect: Black tea inhibited iron absorption more than cocoa, camomile, vervain, and lime flower tea in a clinical trial.

Caffeine Sensitivity

While black tea contains significantly less (approximately half as much) caffeine than a cup of coffee, some people are sensitive to caffeine.

For those with a high degree of sensitivity, the approximately 50 mg in a cup of black tea could potentially trigger sensitivity symptoms like anxiety, restlessness, and poor sleep.

Among the true tea drinks, green tea and white tea typically contain the least caffeine, and may be an option. However, it may be worth consulting with your healthcare provider to discuss these issues.

Does Black Tea Contain Any Nutrients?

If you’re wondering whether black tea contains any vitamins or minerals, the answer is that it does provide some.

It contains a notable amount of manganese and very low amounts of several other vitamins and minerals.

According to USDA data, a brewed cup of black tea contains the following nutrients:

• Calories: 2 kcal
• Carbohydrates: 0.71 g
• Manganese: 23% of the daily value (DV)
• Riboflavin (B2): 3% DV
• Copper: 3% DV
• Folate: 3% DV
• Magnesium: 2% DV
• Potassium: 2% DV
• Iron: <1% DV
• Phosphorus: <1% DV
• Sodium: <1% DV
• Zinc: <1% DV
• Choline: <1% DV

Other Considerations

Lastly, here are some further considerations about black tea that you might find helpful:

• Black tea varieties: Black tea isn’t just one generic drink that is always the same, and there are several different black tea varieties, which range in strength. You can find out more about the different black tea types here.
• Preparation: How you prepare black tea has an influence on its final composition. For example, a longer steeping time will increase the amount of tannins and other polyphenols in the final cup.
• Caffeine content: The brewing method also heavily influences the final cup’s caffeine content, with brewing time and temperature particularly important. Learn more about the caffeine content of black tea.

Preparing Black Tea

It is possible to make black tea quickly using just a cup, a teabag, and boiled water. However, giving the black tea more time and space to brew through the use of a teapot allows it to develop a richer flavor.

Here is a simple process to follow:

• Boil: Boil some water in a kettle or on the hob.
• Prepare teapot: Add either tea leaves (2g per person) or teabags (1 per person) to a teapot, and add the hot water. Note: Some delicately flavored teas may recommend letting the water cool for a few minutes before adding it to the tea.
• Steep: Allow the tea to brew (steep) in the teapot for 3-4 minutes for a more flavorful cup of tea. This longer duration can also increase the caffeine and polyphenol content. However, for those who prefer milder tea, this also increases tea’s bitter qualities due to an increased tannin content.
• Serve: Pour the black tea into individual cups. If adding milk, do this once the tea has brewed; add it straight to the cup after pouring the tea.

Summary

Black tea is a drink that may offer benefits due to its provision of bioactive compounds like theaflavins. While the research is mixed, the current evidence suggests black tea intake may help support gut health, circulation, and blood pressure levels.

However, research has shown that black tea is capable of reducing iron absorption from non-heme iron, so this should be considered in the context of the overall diet.

For more on tea, see this guide to oolong tea.

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