The hidden health dangers lurking in your cup of tea – as experts warn, tea bags could release billions of toxic microplastics into the body

A cup of tea, or four, is a daily ritual for millions of Brits, with the country estimated to consume around 165 million cups a day, around two and a half per person.

While much has been made about the overall health benefits of a brew, a recent study has revealed the terrifying possibility that each tea bag could release billions of potentially harmful plastic particles into your body.

But it’s far from the only health problem linked to a cup of tea. Here, MailOnline explains all the potential hidden health dangers.

Potentially carcinogenic and fertility-reducing microplastics

A shocking study this week suggested that every tea bag you use to make a brew could potentially release billions of dangerous microplastics into your body.

Microplastics are small plastic pieces less than 5 mm long that have become increasingly abundant in the environment over time.

They are found in water, air and now tea. Once in the body, microplastics can penetrate deep into tissue due to their microscopic size.

In experiments, scientists from the Universitat Autònoma de Barcelona tested a number of tea bags made from nylon, polypropylene or polymer filters, mixing hot water and testing the results.

They discovered that the microplastics released in tea were largely absorbed by mucus-producing intestinal cells.

However, they found that some were so small that they could even penetrate the cell nucleus – the part of the cell that houses genetic material.

Although they all released huge amounts of microplastics, the polypropylene tea bags were the worst offenders, releasing around 1.2 billion particles per milliliter, each with an average size of 136.7 nanometers.

The implications of what microplastic exposure means for human health in general, both through tea and other means, are still being explored.

But mounting evidence suggests that plastics may play a key role in the development of early-stage cancer, with healthy cells becoming carcinogenic.

Some scientists have suggested that the presence of microplastics in tissue could increase the risk of cancer, including a mysterious increase in colon cancer in young people.

Others have even found microplastic in human semen and theorized that its presence could play a role in a global decline in fertility.

Esophageal cancer

Some research suggests that drinking piping hot tea can double the risk of developing a form of cancer.

A study of people in Iran found that those who regularly drank tea at a steamy temperature of 60°C (140°F) or higher saw their risk of esophageal cancer increase by 90 percent.

The esophagus is the muscular tube that carries food and drink through the throat and into the stomach for digestion.

The theory is that repeated exposure to hot liquid damages cells, leading to changes that can cause cancer.

Although intriguing, experts have highlighted that most Britons do not drink tea at this temperature due to the habit of adding milk, which cools the tea quickly.

Cancer experts have also said that if the increased risk from high temperatures is real, it is likely a cumulative effect of years of exposure to these glowing liquids.

This means that British people who have had the occasional sip of tea that is too hot are unlikely to have a significantly increased risk of this type of cancer.

Kidney stones

Oxalate is a natural chemical found in many types of plants, including tea.

Although it is harmless for most people, the one in ten Britons prone to kidney stones should limit the amount of oxalate-rich foods and drinks they consume.

If you have too much oxalate over a long period of time, it can contribute to the development of stones.

While they are normally excreted in the urine without any problems, larger kidney stones can be extremely painful and lead to infections or even affect kidney function if left untreated.

It is for this reason that the NHS advises people suffering from kidney stones to limit their intake to just two to three cups of tea per day.

They also recommend that cups be consumed with plenty of milk, as the calcium in them binds to oxalate, neutralizing it and helping to stop the development of the stone.

Possible iron deficiency

Tannins are a type of natural chemical found in tea leaves that have been attributed a number of health benefits due to their antioxidant properties.

However, if you are among the 8 percent of British women or 3 percent of men who are iron deficient, you may want to limit the number of cups you drink each day.

This is because tannins can interfere with the way the body absorbs iron, potentially worsening anemia.

If you are taking iron supplements, experts recommend not drinking tea for two hours before or afterward to ensure you absorb the iron needed to produce the red blood cells that carry oxygen throughout the body.

Beware of hidden caffeine

When most people think of caffeinated drinks, coffee and energy drinks are often the first that come to mind.

But tea is also a little-known source of the stimulant that can come with a host of potential problems that some should be aware of.

While not as caffeine-rich as coffee, an average 8-ounce cup of tea still contains 45 mg of the stimulant.

However, the exact caffeine content of tea can vary widely due to factors such as brewing time, water temperature and type of tea.

A report from the Department of Nutritional Services previously found that a cup of black tea contains between 23 and 110 mg of caffeine.

The NHS recommends people consume less than 600mg of caffeine per day to avoid problems such as anxiety, insomnia, agitation, palpitations, diarrhea and restlessness.

Britons with certain sensitive heart conditions and who are taking medications that may interact with the stimulant may need to limit their caffeine intake, and this may include tea.

Pregnant women are also advised to limit their caffeine intake to just 200 mg per day due to an increased risk of miscarriage or low birth weight.

The stimulant is believed to cause spikes in blood pressure that can affect blood flow to the placenta.

But some studies have suggested that even women who consume less than the 200 mg limit still have an increased risk of having low birth weight babies or premature newborns.

Other scientists have linked expectant mothers who consume caffeine to children having developmental delays.

However, this remains a subject of scientific debate, with some experts suggesting that research linking consumption to problems is exaggerated.

But these experts added that pregnant women should still follow officials’ guidelines on daily caffeine intake limits.

Teeth discolor

One of the most common complaints when drinking tea is discoloration of the teeth.

This is due to the high tannin content of the drink, which can lead to the famous yellow spots.

While this can be unsightly and damage people’s self-confidence, this is purely a cosmetic problem and can be alleviated by maintaining good oral hygiene.