Benefits of Tea

Although health benefits have been assumed throughout the history of using Camellia sinensis as a common beverage, there is no high-quality evidence that tea confers significant benefits. In clinical research over the early 21st century, tea has been studied extensively for its potential to lower the risk of human diseases, but none of this research is conclusive as of 2017.

In regions without access to safe drinking water, boiling water to make tea is effective for reducing waterborne diseases by destroying pathogenic microorganisms.

1.Cognitive effects

Drinking caffeinated tea may improve mental alertness.There is preliminary evidence that the caffeine from long-term tea (or coffee) consumption provides a small amount of protection against the progression of dementia or Alzheimer’s disease during aging, although the results across numerous studies were inconsistent.

2.Cancer

In 2011, the US Food and Drug Administration (FDA) reported that there was very little evidence to support the claim that green tea consumption may reduce the risk of breast and prostate cancer.

The US National Cancer Institute reports that in epidemiological studies and the few clinical trials of tea for the prevention of cancer, the results have been inconclusive. The institute “does not recommend for or against the use of tea to reduce the risk of any type of cancer.”Inconsistencies in study findings regarding tea and cancer risk may be due to variability in tea preparation, tea consumption, the bioavailability of tea compounds (the amounts that can be absorbed by the body), lifestyle differences, and individual genetic differences.”Though there is some positive evidence for risk reduction of breast, prostate, ovarian, and endometrial cancers with green tea, it is weak and inconclusive.

Meta-analyses of observational studies have concluded that black tea consumption does not appear to protect against the development of oral cancers in Asian or Caucasian populations, the development of esophageal cancer or prostate cancer in Asian populations, or the development of lung cancer.

3.Cardiovascular disease

In preliminary long-term clinical studies, black tea consumption showed evidence for providing a small, reduced risk of stroke,whereas, in another review, green tea and black tea did not have significant effects on the risk of coronary heart disease.Two reviews of randomized controlled trials concluded that long-term consumption of black tea slightly lowers systolic and diastolic blood pressures (about 1–2 mmHg), a finding based on limited evidence. A 2013 Cochrane review found some evidence of benefit from tea consumption on cardiovascular disease, though more research is needed.

4.Fracture risk

Tea consumption does not appear to affect the risk of bone fracture including hip fractures or fractures of the humerus in men or women.

5.Weight loss

Although green tea is commonly believed to be a weight loss aid, there is no good evidence that its long-term consumption has any meaningful benefit in helping overweight or obese people to lose weight, or that it helps to maintain a healthy body weight. Use of green tea for attempted weight loss carries a small risk of adverse effects, such as nausea, constipation, and stomach discomfort.