The efficacy and contraindications of black tea

1. Refreshing

Black tea has a good refreshing effect. This is because it contains caffeine, a substance that can directly act on the cerebral cortex cells, making them excited and thus producing a refreshing effect. This will help people concentrate and immerse themselves in their studies and work.

2. Speed ​​up metabolism

Black tea can excite blood vessels and the heart, thereby speeding up blood circulation and making the body's metabolic reactions more efficient. Moreover, during this process, the waste produced by the human body will be quickly excreted through sweat and urine.

3. Antibacterial

Black tea contains polyphenols, an organic substance that can combine with bacterial cells and cause the proteins in them to precipitate, thereby disrupting their physiological functions and achieving the effect of eliminating bacteria.

4. Delaying Aging

Black tea contains many antioxidants, which can effectively slow down the aging of cells and thus play a role in delaying aging.

5. Taboo

1. Patients with neurasthenia should avoid drinking black tea frequently, because its refreshing function will aggravate their condition.

2. Pregnant women should not drink black tea frequently because it contains tannic acid, which will affect their absorption of iron and is not good for the baby.