What is tea?
Globally, people drink over 2 billion cups of tea daily, making this drink the most popular non-alcoholic beverage. Teas that are unhealthy include comfrey, kava kava, black, and other teas.
A warm cup of tea is a refreshing and soothing drink. Globally, people drink over 2 billion cups of tea daily, making this drink the most popular non-alcoholic beverage. Many people enjoy tea for its health benefits, nutrients, and rich flavors. However, is tea bad for you?
While most teas are safe to drink in moderation, a few varieties can have harmful side effects. Learn what you need to know about unhealthy teas and their potential side effects here.
Tea is an ancient drink that was probably invented in China before 2,000 B.C. True tea comes from subspecies of the tea plant (Camellia sinensis), a perennial shrub that grows in Southeast Asia.
Manufacturers use leaves from the tea plant to produce six main types of tea, including:
- Green
- Black
- Dark
- White
- Yellow
- Oolong
Green and black are the most popular and oldest flavors of tea. However, some people prefer the mellower flavors of oolong, white, and yellow teas over the famously bitter green tea.
You can also drink a huge array of herbal teas. Manufacturers use infusions of flowers, leaves, and roots of many plant species to create these teas. For example, many herbal teas contain chamomile and peppermint.
Like true teas, herbal teas may provide medicinal benefits, though more research is needed to understand their effects fully.
Which teas are bad for you?
Most people think of tea as a healthy drink, but not all teas are created equal. Here are fiveunhealthy teas and their possible adverse effects.
Comfrey tea
Comfrey tea is an herbal tea made from the leaves of the comfrey plant (Symphytum officinale). People believe that this drink can help treat several health conditions, including allergies, bronchitis, diarrhea, and rheumatoid arthritis.
Despite these purported benefits, comfrey tea is dangerous because it contains plant toxins called pyrrolizidine alkaloids. When you take comfrey orally, these compounds can damage liver cells and cause sinusoidal obstruction syndrome. This condition occurs when the veins in the liver become blocked and can quickly lead to acute liver failure.
In fact, many countries have banned or restricted sales of comfrey tea and oral capsules because of the risk of liver damage. Avoid buying teas that contain comfrey, and don’t brew comfrey leaves for homemade tea.
Detox teas
Celebrities and social media often promote drinking detox teas as an easy way to improve health and lose weight. Manufacturers argue that these teas cleanse the body of harmful toxins like lead and pollutants. However, there’s no scientific evidence supporting this claim. Studies also show that detox teas don’t lead to long-term weight loss.
The Federal Drug Administration (FDA) doesn’t regulate detox teas, which consequently may contain harmful ingredients and have unadvertised side effects. For example, one study found that an alleged liver detoxification tea instead caused a patient to develop acute fulminant liver failure.
In 2014, the FDA warned consumers not to purchase Toxin Discharged Tea after they detected fluoxetine hidden in the product. Fluoxetine is a prescription drug known as a selective serotonin reuptake inhibitor category. This medication can interact with other common medications like aspirin and chemotherapy drugs, leading to ventricular arrhythmia or sudden death.
Stay away from detox teas to protect your health.
Kava kava
Kava kava is a tea made from the chewed or crushed roots of the kava plant (Piper methysticum Forst). South Pacific Islanders have traditionally used kava as a ceremonial drink for social events like marriages.
This tea also has medicinal properties. It has relaxing effects and may help treat anxiety, menopause, urinary tract infections, and other conditions.
Kava is a controversial tea, though. Some people have reported that kava causes liver damage. Concerns about hepatotoxicity have led several countries to outlaw or restrict the use of kava. These countries include Canada, Great Britain, and Switzerland.
However, several groups have disputed the results of studies on kava’s effects on the liver and argue that contaminants or other drugs may have caused the reported liver injuries.
Still, until researchers more extensively study kava’s impact on the liver and overall health, it’s best to avoid this drink.
Black tea
Researchers have detected heavy metal contamination in many teas, including the popular black tea. One study found that 105 black tea samples from north Iran contained heavy metals like arsenic, cadmium, and lead. These metals can cause decreased cognitive development, lung and skin cancer, skin lesions, and other conditions.
Another study examined 30 commercially available teas, searching for toxic contaminants. The sampled teas included black, green, oolong, and white teas. 73% of teas brewed for 3 minutes and 83% brewed for 15 minutes contained high lead levels that could be dangerous if consumed by pregnant and breastfeeding women.
Limiting your consumption of black tea in particular and preparing this beverage with bottled water may help prevent heavy metal contamination.
Licorice tea
Licorice tea is made from the root of the licorice plant (Glycyrrhiza glabra). This drink contains a bioactive component called glycyrrhizin, which can cause hypertension, hypokalaemia, and increased blood volume when consumed in excessive amounts.
Licorice consumption during pregnancy can even cause children to develop cognitive issues, such as attention-deficit/hyperactivity disorder and poor memory.
The European Scientific Committee on Food recommends consuming no more than 10 milligrams of glycyrrhizin daily. Unfortunately, licorice tea is poorly regulated and often contains unsafe amounts of this compound. A single 250-milliliter serving of licorice tea may have over three times the recommended amount.
Because of the potential side effects and lack of regulation, you should avoid drinking licorice tea.
