Different of effects about black tea

black tea health

What is black tea?
Black tea is a product made from the Camellia sinesis plant. The aged leaves and stems are used to make medicine. Green tea, which is made from fresh leaves of the same plant, has some different properties.

Black tea is used for improving mental alertness as well as learning, memory and information processing skills. It is also used for treating headache and low blood pressure; preventing heart disease, including “hardening of the arteries” (atherosclerosis) and heart attack; preventing Parkinson’s disease; and reducing the risk of stomach and colon cancer, lung cancer, ovarian cancer, and breast cancer. It is also used for type 2 diabetes, stomach disorders, vomiting, diarrhea, and as a diuretic to increase urine flow. Some people use black tea for preventing tooth decay and kidney stones. In combination with various other products, black tea is used for weight loss.

In foods, black tea is consumed as a hot or cold beverage.

Black_Tea_Bag

 

How does black tea work?
Black tea contains 2% to 4% caffeine, which affects thinking and alertness, increases urine output, and may reduce the symptoms of Parkinson’s disease. It also contains antioxidants and other substances that might help protect the heart and blood vessels.

Are there safety concerns?
Drinking moderate amounts of black tea is LIKELY SAFE for most adults.

Drinking too much black tea, such as more than five cups per day, is POSSIBLY UNSAFE. High amounts of black tea can cause side effects due to the caffeine in black tea. These side effects can range from mild to serious and include headache, nervousness, sleep problems, vomiting, diarrhea, irritability, irregular heartbeat, tremor, heartburn, dizziness, ringing in the ears, convulsions, and confusion. Also, people who drink black tea or other caffeinated beverages all the time, especially in large amounts, can develop psychological dependence.

Drinking very high amounts of black tea containing more than 10 grams of caffeine is LIKELY UNSAFE. Doses of black tea this high might cause death or other severe side effects.

Are there interactions with foods?
Iron
Black tea might interfere with the body’s ability to absorb iron. This probably isn’t a problem for most people, unless they are iron-deficient. If this is the case, drink tea between meals rather than with meals to lessen this interaction.
Milk
Adding milk to black tea appears to reduce some of the heart health benefits of drinking tea. Milk might bind with the antioxidants in tea and keep them from being absorbed. However, not all research confirms this. More evidence is needed to determine just how important this interaction, if any, might be.

What kind of effective is black tea?
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

Mental alertness. Drinking black tea and other caffeinated beverages throughout the day helps to keep people alert, even after extended periods without sleep.

Weight loss. Early research suggests that taking a combination product containing black tea extract plus green tea extract, asparagus, guarana, kidney bean, and mate along with a combination of kidney bean pods, garcinia, and chromium yeast for 12 weeks does not reduce body weight in overweight adults.

Low blood pressure after eating (postprandial hypotension). Drinking beverages containing caffeine, such as black tea, helps increase blood pressure in older people who have low blood pressure after eating.

Parkinson’s disease. Some research shows that people who drink caffeinated beverages such as coffee, tea, and cola have a lower risk of Parkinson’s disease. The lower risk seems to be directly related to the dose of caffeine in men but not women. Drinking black tea also appears to be linked with a reduced risk of Parkinson’s disease among people who smoke cigarettes.

Brittle bones (osteoporosis). Early research shows that older women who drink more black tea seem to have stronger bones. Drinking more black tea also seems to be linked with a lower risk of hip fracture in older men and women.

Breast cancer. People who drink black tea do not seem to have a lower risk of breast cancer.

high blood pressure. Some early research suggests that people who regularly drink green or black tea have a lower risk of having high systolic blood pressure, which is the top number of a blood pressure reading. However, most research shows that drinking black tea does not reduce blood pressure in people with normal or high blood pressure.

Brittle bones (osteoporosis). Early research shows that older women who drink more black tea seem to have stronger bones. Drinking more black tea also seems to be linked with a lower risk of hip fracture in older men and women.

Diabetes. Early research suggests that taking an extract of black and green tea does not improve HbA1C levels in people with diabetes. HbA1C is a measure of blood sugar control. Other early research suggests that drinking at least one cup of black tea per day is not linked with a lower risk of developing type 2 diabetes in Japanese adults.

Leave a Reply

Your email address will not be published. Required fields are marked *