Water is the most fundamental and important component of the human body, the source of life. In a healthy adult, 50% to 70% of body weight is water, and all life and metabolic activities depend on water. Therefore, we often hear people say drink more water when you have a cold, drink more water when you have a cough, drink more water for constipation, or just drink more water in general… But is drinking 8 glasses of water (about 2000 ml) every day really good for health? Dr. Liu Yu, Director of the Spleen and Stomach Diseases Department at the Jiangjin District Traditional Chinese Medicine Hospital in Chongqing, explains whether drinking large amounts of water is beneficial to health.
What diseases can occur from drinking too much water?
Dr. Liu Yu says that according to traditional Chinese medicine theory, the metabolism of fluids is completed through the coordinated action of the digestive system, spleen, lungs, kidneys, and bladder. When water enters the stomach, especially when cold water enters our 37°C body, it requires the transformation of spleen yang and warming of kidney yang. At the same time, under the regulation of lung function, it participates in the body's metabolism. If there is an excess of cold water in the stomach, it will require more calories, i.e., the body's yang energy, to transform the fluids. Over time, with excessive consumption of yang energy, yang deficiency leads to coldness, causing cold stomach, where symptoms such as stomach pain and indigestion appear when cold food is consumed.
After water vapor rises to the lungs and begins to descend, the portion reaching the bladder needs to change from vapor back to fluid, a process that requires the kidney to expend energy. If one drinks large amounts of water over a long period, it can injure the kidneys, leading to cold kidneys and deficiency of kidney yang. Women may experience gynecological issues, while men may have prostate problems. Most will also experience frequent urination, urgency, and cold sensitivity.
According to traditional Chinese medicine, the spleen is associated with earth and prefers dryness over dampness. Excess fluids in the body that are not properly transformed and unsmooth qi movement can injure the spleen, manifesting as reduced digestive absorption function. Clinically, this can present as abdominal distension, poor appetite, bland taste, chest fullness and nausea, loose stools, and even edema. Additionally, it can lead to phlegm-dampness formation, which has significant harm to the body. Dr. Liu points out that the “phlegm” referred to in traditional Chinese medicine does not only refer to the sputum expelled from the respiratory tract but also encompasses waste products generated from improper fluid metabolism in the body. These wastes, carried by qi and blood circulation, spread throughout the body, accumulating in different areas and causing various diseases. The overall characteristics of phlegm-dampness can be summarized as phlegm-dampness accumulation, with features such as obesity, abdominal fullness, sticky mouth, and thick greasy coating. This can be accompanied by hypertension, diabetes, dyslipidemia, obesity, and other metabolic syndromes. It predisposes individuals to chronic gastritis, colitis, cervical spondylosis, orthostatic hypotension, and stubborn acne. Women with a phlegm-dampness constitution may experience delayed menstruation or amenorrhea, while men may have infertility.
How should you drink water according to traditional Chinese medicine?
The main sources of water in the human body are: about 50% from drinking water, approximately 40% from food, and roughly 10% from internal metabolic production. The primary ways the body eliminates water are: about 1500 ml excreted by the kidneys in urine, about 350 ml exhaled by the lungs, around 500 ml evaporated through the skin and sweat, and about 150 ml discharged with feces. Considering both intake and output, fluid metabolism generally totals around 2500 ml, which is why people commonly believe they need to drink 8 glasses of water daily.
Dr. Liu reminds us that individuals have different constitutions, and the functions and capabilities of organs involved in fluid metabolism directly affect the amount of water excreted. The digestive and transformative capacity of the spleen and stomach influences fluid absorption, while the dispersion and regulation capacities of the lungs and kidneys impact fluid utilization and excretion. Therefore, everyone should determine their daily water intake based on their own physical condition.
Dr. Liu points out that drinking water can be summarized in eight words: small amounts, multiple times, slow sipping, and warm water. This approach is suitable for most Chinese people's constitutions.
Therefore, do not blindly drink large amounts of water. If transformation is insufficient, the water entering the body can easily turn into toxic fluid, which cannot nourish the five zang organs and six fu organs, and can create pathological factors. Such drinking is not beneficial to health.
Editor: Zhang Zhiyuan