Excessive tea drinking can increase body fluids, adding burden to the heart and kidneys; overly strong tea can excite the brain, causing rapid heartbeat, frequent urination, and insomnia; excessive intake of caffeine and other substances in tea is also unfavorable for certain diseases.
It is evident that tea drinking requires grasping the concept of "moderation." The daily amount of tea each person drinks is related to factors such as tea-drinking habits, age, health status, living environment, and customs.
Generally, healthy adults who are habitual tea drinkers can consume about 12 grams of tea per day, ideally divided into 3-4 brews.
For those with high labor intensity, significant physical exertion, and large food intake, or for those engaged in high-temperature work and exposure to toxic substances, a daily tea consumption of about 20 grams is also appropriate.
People whose diets include beef and lamb as staples or who consume excessive fatty foods, as well as those who smoke and drink alcohol, may appropriately increase their tea leaves用量 (Note: The original Chinese text "用量" means "dosage" or "amount used". The translation should reflect this).
However, the tea consumption for the elderly, children, pregnant women, etc., should be appropriately reduced, generally focusing on drinking light tea.
For the elderly, especially those over 50 years old, tea drinking must avoid excess and strength, as higher intake of caffeine and other substances can lead to symptoms such as insomnia, tinnitus, blurred vision, irregular heartbeat, and excessive urination. Elderly people with heart conditions should drink warm, light tea and avoid tea in the evening; it is better to drink plain water after dinner.
As elderly people age, the secretion of various digestive enzymes in their digestive system decreases, leading to reduced digestive function. Drinking large amounts of tea can dilute gastric juice, affecting the digestion and absorption of food. Simultaneously, stomach acid is diluted, reducing the defensive function of the gastrointestinal tract against pathogens, making it easier to contract gastrointestinal diseases once pathogenic bacteria enter.
Most elderly people have poor teeth and consume less fibrous vegetables. Coupled with less physical activity, their intestinal peristalsis slows down, making them prone to constipation. If they often drink strong tea, the tannic acid in tea binding with proteins in food forms large, indigestible protein masses, further worsening constipation.
Renal function gradually declines in the elderly, often leading to symptoms like urinary incontinence. Excessive consumption of strong tea, with the diuretic effects of caffeine and other substances, will inevitably increase the burden on the kidneys and worsen urinary incontinence symptoms, bringing greater suffering to the elderly.