These days, everybody talks about green tea and how good it is for your health but what about black tea? Is black tea good for you? Does it have any health benefits? Both types of tea come from the same plant, so surely black tea isn’t that bad for you?
But to see whether black tea is good or bad, we decided to investigate and learn how black tea is produced and what compounds it contains. We also decided to look at the current research and any evidence that says that black tea is good for you.
What is black tea?
Black tea has been drunk for centuries and is the second most popular drink in the world (after water). It comes from the tea plant Camellia sinensis and is more heavily oxidised than green or white tea.
Oxidation is a natural process (although it can be controlled) where the leaves are bruised, their cell walls are broken down, tannins are released, and they turn brown. This results in the unlocking of new plant compounds. The amount of oxidation a tea gets distinctly affects its flavour, smell, colour and chemical composition.
Camellia sinensis tea plant thrives in tropical climates. It is thought to have originated in China although variations also grow in places such as the Darjeeling and Assam regions of India, Africa, South America, Sri Lanka, Taiwan, Australia, Hawaii, the Pacific Northwest, California and Central America. Some black tea is even grown in the UK.
There is a large assortment of black tea varieties including Lapsang Souchong and Dianhong from China, Assam, Darjeeling and Nilgiri from India, Ceylon from Sri Lanka, Sun Moon Lake from Taiwan, Nepali from Nepal and Rize from Turkey.
Familiar blends include Earl Grey where black tea is infused with Bergamot oil and English breakfast where robust, rich teas are blended to accompany milk and sugar.
Although they tend to be stronger and more full-bodied, some black teas which are grown in more mountainous areas like the Himalayas (such as Darjeeling first flush) are less oxidised and have a greener quality.
Not all black teas are created equal
The quality of black tea can significantly differ between brands and is influenced by several factors.
The type and health of the tea plant
Different types of black tea have their own unique characteristics with varying benefits. But the health of these plants is vital for good quality tea, which all depends on the production methods.
These are incredibly important for the production of healthy plants. Good soil composition is essential as it needs to be alive and fertile with a balanced pH, an abundant mineral content, appropriate moisture levels and the right temperature. A climate with the right amounts of rainfall, moisture, heat, humidity, sunshine and daylight is also crucial.
How many pesticides, herbicides, and other chemicals are used in the growing and harvesting process? Are sustainable farming methods being employed to ensure long-term durability and protection of the plants, the soil, and the environment? Not only will these factors influence the quality of the tea, but also how it affects your overall health and wellbeing.
Plantation practices and bush management
Timing is everything when it comes to nurturing a flavourful and nourishing cup of tea. How intimately and intuitively are the farmers working with the plants? The right leaves need to be plucked at particular intervals to ensure a high polyphenol and caffeine content, and superior quality tea.
Processing of the leaves
Is the production large-scale and standardised or more hands-on and traditional? The time taken to harvest under the right conditions and maintain the health of the leaves can severely impact the calibre of the tea.
Is it organic?
If you choose organic tea, it will have been grown without the use of man-made fertilisers and other chemicals, and it will have been sustainably produced while protecting the environment. This should mean a superior tea that is much better for you.
The cheaper black teas will most likely be of lesser quality, and beware of microplastics in your teabags.
In 2010, a Which survey found that only one brand of tea bags didn’t contain polypropylene (a plastic used to heat seal the tea bags). Even organic brands use it. This not only means that the tea bags are not compostable, but you are also ingesting traces of plastic when you drink. Although polypropylene is classified as #5 which means it’s a safer, non-leaching, less toxic plastic to use, avoiding plastics altogether is probably wiser.
Did you know that tea bags are usually filled with the dust and fannings of broken tea leaves which have lost most of their essential oils and aromas? Switching to loose leaves will ensure you get the best form of tea. They have the freedom to swirl and expand, releasing the flavour, leading to a more aromatic tea with a fuller, yet more subtle taste.
Does black tea have any nutritional value?
To determine whether black tea is good for you or not, we should look at what we are consuming when drinking it.
In general, black tea will contain the following:
It’s not just green and white tea that contain antioxidants; black tea does too. While green tea is famous for the fact that it contains the antioxidant EGCG (epigallocatechin-3-gallate), high levels of polyphenols (or flavonoids) called theaflavins are unique to black tea.
Theaflavins and thearubigins (also found in black tea) may help to defend fat cells from free radical damage, and protect against high cholesterol and hyperglycemia.1
Theaflavins may also help to reduce inflammation in the blood vessels and help them to dilate. The potent antioxidant profile of black tea makes it fantastic for your overall health and wellbeing.2, 3
While this can have adverse effects if you drink too much or are intolerant, there are some benefits to caffeine too. For example, it can uplift your mood, temporarily increase energy and enhance brain function.4 It can also boost your metabolism and may help to burn fat.5, 6
Various minerals including magnesium, potassium, zinc and manganese and vitamins B2, C, and E
These are all great for your general wellbeing, and contribute to the many health benefits black tea has to offer.
Amongst other things, magnesium and zinc need to be continuously replenished as our bodies heavily rely on them and they can quickly become depleted, particularly during times of stress.
Vitamins C and E add to the powerful antioxidant value of black tea.
An amino acid that helps to calm the brain and nervous system, L-theanine relieves stress and anxiety and aids sleep. Also, when teamed with caffeine, L-theanine improves alertness, helping you to concentrate and focus while remaining calm.7, 8, 9, 10
Does black tea have any harmful compounds?
If tea is non-organic, it is more likely to have been exposed to pesticides, which can be harmful to health. However, if it is organic, it may still have been exposed if a neighbouring farm is using them.
Some areas are notoriously more polluted than others like China which has high levels of soil, water and environmental pollution and some parts of India. For example, in 2012, Greenpeace exposed excessive pesticide use in Chinese tea. They tested samples from nine well-known brands and found a large variety of pesticides in all of them, including illegal pesticides in twelve of the samples.
However, that doesn’t mean that all tea from these places is contaminated, but it would be wise to do your research and find a brand that has been produced in an area you feel comfortable with.
Some teas, including black tea, may also contain significant levels of lead and aluminium, both of which can contribute to heavy metal toxicity. This can severely impact your health, with the power to affect almost every organ in your body and cause inflammation, which is commonly considered to be at the root of most illness and disease.
For more information about toxins in your tea read this article.
What health benefits does black tea have?
May improve gut health
Over 70% of your immune system lives in the gut, so it’s vital to look after your digestive health. Recent research shows that dietary polyphenols (like those found in black tea) support beneficial gut bacteria.11
Black tea is known for its antibacterial properties, and it may also reduce the risk of Helicobacter pylori infection.12
One study13 also found that black tea has antidiarrheal effects.
More research is needed, but some studies have shown that the antioxidant flavonoids found in black tea (theaflavins and thearubigins) can modulate how your blood vessels respond to physical and emotional stress. As flavonoids help to reduce inflammation, this may decrease plaque formation in the arteries.
Research also shows that regular consumption of black tea may lower ‘bad’ LDL cholesterol, as well as having the potential to slightly lower blood pressure.14, 15, 16, 17
A few studies link black tea to a reduced risk of strokes and heart attack although it is unclear whether this is just down to drinking black tea or if other lifestyle factors of tea drinkers are responsible. One study showed that drinking as little as three cups a day could reduce the risk of heart disease.18
The bottom line is, if you want to prevent heart disease, regularly drinking good quality black tea is certainly not a bad idea as black tea may be good for your heart.
The polyphenols found in green tea have been associated with reduced cancer risk for some time. But there is now accumulating evidence that black tea may also have beneficial effects.
One study reports that black tea may reduce the risk of colon cancer in both men and women, and the pooling of data from several breast cancer trials suggested that black tea might have a positive effect on late-stage breast cancer.
Regular black tea drinking may also protect non-smoking women from lung cancer, and reduce the risk of prostate and skin cancer.19, 20
The theaflavin in black tea (TH-2) has been shown to encourage the programmed cell death (apoptosis) of colon cancer cells, and it also has the potential to halt tumour growth.21 All this definitely warrants further investigation.
Diabetes and blood sugar balance
A small amount of research suggests that the theaflavins and other compounds in black tea can noticeably improve the way that the body responds to and metabolises insulin, lowering and balancing blood sugar. However, studies also show green tea to be more effective at this than black tea due to the EGCG (epigallocatechin gallate) that it contains.22, 23
May help prevent osteoporosis
There’s not a great deal of research supporting this, but some studies have linked regular drinking of black tea to a decreased risk of fractures in the elderly, with an increased bone density of between 2.8% to 5% compared to non-tea drinkers.24
May protect teeth and oral health
The polyphenols, including theaflavins, and higher levels of tannins found in black tea may help to prevent dental cavities as they inhibit salivary amylase, an increase of which can lead to tooth decay25.
A small Indian study26 also found that black tea may protect against mouth cancer as it can reduce oral leukoplakia, a potential precursor to the disease.
Anti-ageing benefit for the skin
The antioxidants and vitamins C and E in black tea are all great for healthy, glowing skin and one animal study found that black tea was superior to green tea at effectively suppressing a collagen degradation enzyme, reducing sun damage and wrinkles.27
Does black tea have any side effects?
Effects of black tea on stress, anxiety and insomnia
Black tea contains caffeine which some people find harder to tolerate than others, particularly if they suffer from anxiety as it can cause blood sugar spikes and exacerbate the body’s response to stress.
Excessive caffeine can also affect sleep, so it’s probably not a good idea to consume it if you have insomnia.
People often know when they have had too much caffeine as it can cause ‘the jitters’ where there is a feeling of nervousness and edginess. Occasionally, too much caffeine can also cause palpitations and headaches.
Black tea and weight loss
Limiting your caffeine intake may be a good idea if you are struggling to maintain a healthy weight as the blood sugar spikes caused by drinking too much (more than 400mg of caffeine a day28) have the potential to affect your cortisol levels, leading to weight gain, particularly around the middle.
However, if you drink black tea in moderation, this may have a positive effect on weight management and weight loss. Black tea has been shown to improve gut health by decreasing the percentage of bacteria associated with obesity and improving the growth of beneficial bacteria.29
Having a better balance of ‘good’ and ‘bad’ gut bacteria improves digestion and reduces inflammation30 which may aid weight loss.
Is black tea safe during pregnancy?
Although it is unclear as to whether caffeine can cause complications during pregnancy, the American College of Obstetricians and Gynecologists recommend limiting it to 200mg a day (between two to five cups of black tea a day depending on the strength).
Black tea affects iron absorption
Drinking black tea with a meal can inhibit the absorption of non-heme iron by up to 70% (from dairy, eggs and plant foods).31 You need to keep this in mind if you are anaemic and try and drink black tea about an hour after a meal instead. Vegetarians and vegans should also be aware of this fact to avoid anaemia.
Black tea and teeth
If you drink a lot of black tea, the tannins can stain your teeth. However, at the same time, black tea offers some protection to your teeth and can reduce tooth decay.
Too much caffeine can also affect the absorption of some prescribed medication, so it’s important to check this with your GP.
Conclusion – Is black tea good for you?
So, in general, due to the vitamins, minerals and powerful antioxidants it contains, it looks like black tea is actually quite good for you. In some areas, it is even better for you than green tea due to its exceptionally high levels of theaflavins and thearubigins.
Black tea’s impressive profile means that it is highly beneficial for your overall health and wellbeing. And although more investigation is needed, it shows tremendous potential when it comes to cancer prevention, improving heart health, and supporting several other health issues.
But like most things, drinking black tea in excess may have a negative effect, particularly if you suffer from stress or anxiety, are struggling to lose weight, are anaemic, or taking certain prescribed medications.
The positive (or negative) effects much depend on the quality of black tea that you buy, how it is produced and whether or not you choose loose leaf tea. This will determine not only any health benefits but also the flavour and aroma.
How you brew your tea is also significant. A British study32 published in 2000, found that although they are released at lower brewing temperatures, the antioxidants in black tea are greatly enhanced, potentially almost 10-fold, by using near boiling water (90 degrees), and they infuse within the first two brewing minutes.
Interestingly, they also found that tea bags inhibited the antioxidant release of black tea, and drinking it with milk also decreased the polyphenols, particularly cow’s milk which may be due to its high-fat content.
With this in mind, drinking your tea without milk and sugar will mean that you gain more of its incredible health benefits.
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