1. Individuals with iron-deficiency anemia: Tannins in tea can interfere with the body's absorption of iron, worsening the anemia.
2. Individuals with neurasthenia: The caffeine in tea can be stimulating, increasing basal metabolism and exacerbating insomnia.
3. Patients with active gastric ulcers: Caffeine in tea stimulates gastric acid secretion, worsening the condition and hindering ulcer healing.
4. Individuals with urinary tract stones: Oxalate in tea can lead to an increase in stone formation.[Chinese Cuisine]
5. Individuals with poor liver function: Most of the caffeine in tea is metabolized by the liver. Drinking tea can increase the burden on the liver for those with compromised liver function.
6. Individuals with constipation: The tannins in tea have an astringent effect, which can slow down intestinal peristalsis and worsen constipation.
7. Lactating women: Caffeine from tea can pass into breast milk, potentially causing infantile colic, anemia, and disrupting the baby's sleep.
8. Individuals with heart disease: Excessive tea consumption can lead to a rapid heartbeat and, in some cases, arrhythmia.
9. Pregnant women: Excessive tea consumption can result in a low birth weight and a weaker infant.
10. Individuals who are intoxicated: Alcohol is a significant stimulant to the cardiovascular system. The caffeine in tea can also increase the heart rate. The combined effect can be very dangerous for individuals with poor heart function.