Drinking Green Tea on an Empty Stomach
Green tea contains tannins and catechins, which have a mild acidic nature. Drinking it on an empty stomach can increase acid levels in the gut, leading to discomfort and nausea. In severe cases, these compounds may cause stomach ulcers or acid reflux.
Additionally, the caffeine in green tea may stimulate the digestive system, inducing nausea if consumed when the stomach is empty.
Drinking Tea Immediately After Meals
Green tea is rich in tannins, which can bind to non-heme iron (the type found in plants), reducing iron absorption into the blood. This may result in iron deficiency, especially hazardous for those at risk of anemia or pregnant women.

Mistakes to Avoid When Drinking Green Tea
Not only does tannin affect iron absorption, but it can also interfere with the absorption of other minerals like calcium and magnesium. Drinking tea right after a meal may reduce the benefits of the nutrients from your food.
Consuming Overly Strong Green Tea
Green tea contains caffeine, and brewing it too strong will result in higher caffeine levels. This may lead to insomnia, difficulty falling asleep, or light sleep. Caffeine can also induce anxiety, stress, and even agitation in some individuals, especially when consumed in large quantities.
Strong green tea has higher tannin content, which can stimulate acid production in the stomach, leading to stomach aches, nausea, and even stomach ulcers, especially for those with a history of stomach issues.

Health Hazards of Drinking Green Tea Incorrectly
Drinking Green Tea Late in the Day
Information is for reference only.