Secret Side Effects of Drinking Tea, Says Science
Our minds may go straight to coffee when we think of the world's favorite drink. However, tea is actually the cheapest and most widely consumed beverage around the globe. Research shows that the list of benefits for drinking tea is extensive, with outcomes like reduced inflammation, decreased risk of heart disease and chronic illness, lowered blood sugar, and much more.
Even though tea is such a popular choice for comfort and healing, it doesn't come without some potential downsides. Read on to see what science says about the possible negative effects of drinking tea, and for more, don't miss The 6 Best Teas To Slow Aging, Say Dietitians.
You may interrupt your body's natural rhythm
Depending on what tea you choose, you may be consuming more caffeine than you realize. Black, white, and green teas average anywhere from 14-61 milligrams of caffeine per serving. Although it's not as much as a cup of coffee (about 96 milligrams per cup), it still has the potential to knock our body's natural circadian rhythm off balance.
Our circadian system is another way of saying the rhythm our bodies follow over a 24-hour period, including the time we are awake and asleep. Our rhythm can be knocked off balance from things such as light, stress, work, and caffeine. It's important to maintain our natural rhythm because this helps us feel more alert during the day, sleep better at night, and maintain overall better health.
If we drink too much caffeinated tea in the afternoon or evening, it could disrupt our sleep schedule, which would also disrupt our circadian rhythm. And research shows that a consistently disrupted circadian system can lead to cardiovascular issues, mental health problems, weight gain, and a weakened immune system. So next time you go to grab a cozy nighttime tea, try switching your green tea for an herbal one!
You may increase your risk of esophageal cancer
This one may come as a surprise, but drinking hot tea has actually been linked to esophageal squamous cell carcinoma (or esophageal cancer). In a study focused on Northern Iranian populations, it was discovered that drinking larger quantities of hot black tea was among one of the leading causes of esophageal cancer. Other studies have found similar results, noting that both hot coffee and hot tea have been known to cause lasting damage to the esophagus.
Researchers are still trying to find the exact explanation for this, but many studies believe it has to do with the internal temperature of our esophagus. For example, if our tea is around 150 degrees Fahrenheit, it is said that our esophagus could reach a temperature of up to 127 degrees Fahrenheit. Maybe it's time we try some iced tea for the summer!
You may decrease your iron levels
Tea can have amazing health benefits, but studies show that those with anemia or any other type of iron-related deficiency may want to think twice. According to a Food Science and Nutrition study, both black and green tea have been proven to limit iron bioavailability by up to 94%. The bioavailability of something we consume is important because it is the measurement of how much a nutrient is absorbed by our body.
A Current Developments in Nutrition report states that the tannins found in tea may be to blame for the changes in iron absorption in the body. Tannins are a natural compound found in certain teas, wine, and chocolate, and they have been proven to lower the bioavailability of iron after consistent consumption. When you have low levels of iron, you may experience things like exhaustion, restlessness, dry skin, and headaches.
You may have to use the bathroom more often
Black and green teas are considered to be diuretics, which are substances that lead to frequent urination. This occurs because diuretics naturally increase levels of sodium in the kidneys, which the body naturally expels along with water. Although tea is sometimes prescribed to people who are retaining too much water, it can often lead to dehydration for someone who isn't struggling with water retention.
According to a report in The Pharma Innovation Journal, the diuretic nature of green and black tea can lead to an imbalance of electrolytes and dehydration. This can then cause things like lethargy, increased or irregular heart rate, and intense headaches.
You may experience constipation
Among the many natural compounds found in tea, theophylline is a common one to take note of. This compound is found in both coffee and tea, and is sometimes used to smooth airway muscles for asthma patients. Although it has its breathing benefits, it can also cause some mild but annoying side effects.
According to a report from the Internal Agency for Research on Cancer, consuming theophylline from tea can lead to gastrointestinal disturbances. Other sources also state that theophylline has been known to cause constipation and nausea. So if you're someone who already experiences stomach problems from time to time, you may want to keep an eye on how your favorite cup of tea affects your bathroom habits.
A previous version of this article was originally published on July 19, 2021.