Drinking tea is a tradition that has been in place for many centuries now. You or someone you know starts their day with a cup of tea. And the same way people have questioned the safety of coffee is the same way you should think about tea.
For the most part, people think of drinking tea as a harmless way of consuming antioxidants. They also believe that this drink can boost their immune systems and ward off some diseases.
Is any of this true? Should you be drinking as much tea as you do now? Here is what you need to keep in mind, based on several studies conducted on the same.
Tea consumption and immune system benefits
Other than water, tea is one of the most affordable drinks on the planet. As a result, many people reach for this drink in the morning as well as other times in the day. Evidence shows that the Camellia sinensis plant has tons of medicinal properties, some of which point to warding off cancer.
This plant brings about different kinds of teas that undergo varying levels of oxidization. Black tea is the most processed form and has the most caffeine, while white tea undergoes little or no processing. When people talk about the health benefits of tea, it mostly refers to green tea.
This form undergoes some oxidization, less than that of black but more than white. It contains some polyphenolic compounds which have proven to be beneficial in boosting the immune system. They include (−)-epigallocatechin-3-gallate (EGCG), (−)-epigallocatechin (EGC), (−)-epicatechin-3-gallate (ECG) and (−)-epicatechin (EC). Additionally, it contains flavanols.
One cup of green tea should contain about 350 mg of tea solids, 6% caffeine. The rest are mostly catechins with EGCG taking up the most part. This compound is highly beneficial in the fight against cancer. Black tea has an almost similar makeup, with some differences in play owing to the difference in processing.
Tea and cancer prevention
Most reports on tea indicate that its compounds are effective in the fight against cancer. At present, there are more than one thousand such publications on this. The studies point to the presence of catechins and theaflavins as the main contributors to this prevention.
The cancers in play include breast, skin, lung and prostate. Studies show that these can have an inverse relationship with tea consumption. Let us go deeper into this:
Many studies have concluded that the active tea compounds can be beneficial when it comes to squamous cell carcinoma of the skin. One such study involved the consumption of black tea, accounting for brewing time.
The results showed that people who drank hot black tea had a lower risk of getting this form of cancer. Based on the data, brewing time, the temperature and the concentration of the drink, all played a part in the likelihood of the disease. Another study took place, this time involving the consumption of black tea and citrus peel. Those who took this combination were at less risk of getting cancer.
Tea consumption is also effective in the fight against cutaneous malignant melanoma. Tea is rich in polyphenols. In one such study, the researchers relied on polyphenon E ointment to treat anogenital warts.
They studied a group of immunocompetent men and women who applied the ointment in varying doses for sixteen weeks. Clearing warts took place at a rate of up to 50%, pointing at the efficacy of the treatments.
Many studies point to green tea having a positive effect on this form of cancer. In this line, a trial took place involving 42 asymptomatic patients who had PSA elevations with hormone therapy. They consumed up to six grams of green tea each day in six sessions.
Every gram had up to 100 calories and 46 mg of caffeine. One patient’s baseline PSA values dropped by up to 50% and did not continue for more than two months. For most of the other patients, the values increased by 43% in the first month. Green tea toxicity occurred in 69% of the patients.
Another study took place in China, involving 130 patients who had histologically confirmed adenocarcinoma of the prostate. Their risk of PCa reduced as they increased their green tea consumption. The more they drank the beverage and increased their amounts, the more the risk lowered.
Many other studies have taken place, with some pointing to beneficial effects, while others show no changes.
Studies that have taken place along this line show that tea consumption can reduce lung cancer chances. Such was the case in a study that took part in Uruguay. Another took place in China, where non-smoking women took part in the research.
They had a low chance of this form of cancer, which only reduced the more they consumed green tea. In Taiwan, 241 lung cancer patients took part in a case-control study. The results showed that patients who consumed less than one cup of green tea each day and had exposure to fumes and smoking had a higher chance of getting lung cancer.
These people also had a family history of this disease. The same did not hold for those who drank more than one cup of green tea each day. The latter group had a reduced risk.
Results as to the relationship between this cancer and the consumption of tea have been inconsistent. One study showed that people with stage I and II cases had a lower chance of reoccurrence if they consumed more than five cups of green tea a day.
That was in comparison to those who drank fewer cups. The first group also remained disease-free for a longer time. Another research took place, this time involving black tea. The results showed that those who drank black tea were more at risk of developing this form of cancer.
A meta-analysis performed on these and other studies concluded that green tea paved the way for a lower risk – while black tea increased the risk of getting breast cancer.
This research holds in many studies. One study involved 5,617 cases of breast cancer, where the researchers looked into incidences and reoccurrence. Based on their stats, they concluded that drinking more than three cups of green tea worked in reducing the incidence of cancer.
However, some studies state that there is no association between green tea consumption and reduced breast cancer risks. There is thus more need for research on this.
Taking tea has been proven to aid in the warding off of some cancers. Green tea, for example, lowers the risk of esophageal cancer. That is, according to a case-control study conducted in Shanghai. Another study took place in Yoshimi, where respondents were in three groups.
They all drank different amounts of green tea. Some drank less than three, others four to nine while the final group drank more than ten cups. Those in the last group had a reduced risk for cancers of the lung, liver and colon. Other studies have shown that taking black tea can reduce the chances of colon cancer.
A big study took place involving 60,567 Chinese men aged 40–74. The researchers looked into whether taking black tea had any effect on the incidence of colorectal cancer. The study took place over the five years that followed, in which there were 243 incidences.
From the data collected, the results showed that taking green tea at least three times a week reduced the chances of getting this disease. However, these results were only present in non-smokers.
Tea and the heart
Taking tea has been shown to aid in cardiovascular and metabolic functions. A study took place involving more than 40,000 Japanese adults who drank more than five cups of green tea daily.
The results showed that they had a 26% lower risk of heart attacks or strokes. They also had a 16% lower risk of death. These results were in comparison to people who drank less than one cup of green tea daily.
A meta-analysis took place involving eighteen studies on the effects of tea on the heart. From this, the conclusion was that those who drank green tea stood a 28% lower chance of coronary artery disease.
That was in comparison to people who drank green tea in small doses. Regarding black tea, few effects on heart health were present.
Tea and Diabetes
Research shows that drinking tea not only improves insulin sensitivity, but it also reduces the risk of developing type II diabetes. Studies show that adding milk to your tea reduces these insulin effects.
The positive impact of tea owes to the presence of polyphenols, which prevent inflammation. A 2009 survey showed that drinking up to three cups of tea daily can reduce the chances of diabetes by as much as 40%.
Tea and Arthritis
Tea is rich in polyphenols, more so green tea. And with its EGCG compound, you can count on it to have more antioxidant effects than vitamins. Some studies also suggest that taking tea can preserve cartilage and bone.
In one such case, women who drank as many as three cups of tea daily had less risk of rheumatoid arthritis. The same did not hold for women who did not take any tea.
Are all teas good for your immune system?
Seeing how some teas can be beneficial to your health may have you running to the store to stock up on these immune boosters. But not so fast – not all teas on the market will offer you a boost in health. Some may even have the opposite effect.
In recent years, there has been an increase in detox teas, which people believe flush out toxins. There is also a belief that these drinks aid in weight loss. The thing is that these teas are full of diuretics and laxatives in most cases. Unless you are making the drink yourself, avoid using such teas. In the long term, they can be harmful to your health.
Also, tea lattes and other such drinks available in cafés may not be the best options. Often, they contain high amounts of sugar, which take away from their benefits. Sure, they may taste great and may have you coming back for more. In the long run, they could pave the way for the development of diseases such as type II diabetes. The same goes for bubble teas, which are often full of carbs and calories.
Not all herbal teas are good for you, and some may even trigger allergies. The thing with herbal blends is they often contain more than one herb and can have fruits and spices. Taking these can cause a harsh reaction. If you must use these drinks, ensure you are aware of what is in the tea before consuming it.
Should you drink tea to boost your immune system?
While most studies on this drink tend to be conflicting, there is enough evidence to suggest that tea can improve your health. That said, you should keep in mind that tea contains caffeine. As such, you should keep your consumption below the 400 mg daily limit, lest you suffer adverse effects.
Most results show that the drink will improve your health and not hurt you unless you go over the caffeine limit. Note that while this beverage may improve your health, most of the work falls on your shoulders. You should thus work on eating right, exercising and hydrating as you increase (or not) your tea consumption.