When we are in a high-pressure environment, in addition to feeling obvious tension, rapid heartbeat, and shortness of breath, our bodies are also undergoing subtle changes, and the pressure will trigger higher-level "alarms". In fact, suddenly feeling "stressed" may be due to a simple reason - drinking too little water! Have you been feeling a lot of pressure lately? People who don't drink enough water and drink less water every day may be more prone to collapse when facing the same pressure. In August 2025, a study published in the Journal of Applied Physiology, a subsidiary of the American Physiological Society, found that people who drink less than 1.5 liters of water per day have significantly higher levels of the main stress hormone cortisol when faced with stress. The study selected 32 participants and divided them into two groups based on their daily water intake: the first group drank less water at a rate of 0.9-1.7 liters per day, and the second group drank more water at a rate of 3.2-5.6 liters per day. Their saliva samples were collected to measure cortisol levels. The final study found that when faced with significant stress, regardless of whether they drink too much or too little water, everyone subjectively experiences "anxiety" and a faster heartbeat. But on an invisible physiological level, people who drink less water are paying a high health price - their stress hormone levels have skyrocketed by 55%. This "internal overreaction" of the body is closely related to the risk of heart disease, diabetes and depression. In addition, research has found that drinking too little water is associated with a stronger responsiveness of cortisol to acute stress. Note that we don't need to drink water only when we feel thirsty, we can make a simple judgment based on the color of our urine. In other words, the darker and darker the color of urine, the stronger the stress hormone response when facing greater pressure. The final research also provides a solution: to improve/reduce the health impact of stress on the body, the method is actually very simple, which is to drink plenty of water in moderation every day! How to drink water healthily? Many people drink water inefficiently. 1. How much do you drink? ——It's about "8 glasses of water" and "8 glasses of water per day", which seems to be the widely recognized daily water intake. But how much is 8 cups of water? According to the "Chinese Dietary Guidelines for Residents (2022)", under mild climate conditions, the appropriate daily water intake for adult males is 1700 milliliters, and for females it is 1500 milliliters. If it is a cup with a capacity of about 200 milliliters, then it is approximately 8 cups. However, various factors such as body shape, climate, age, and physical activity can all affect an individual's water demand. Therefore, the recommended daily water intake still varies from person to person. If the exercise volume is high and sweating is excessive, it can be increased to 2000-3000 milliliters. Elderly and pregnant women need to adjust according to their physical condition. When to drink? ——It is recommended in the "Chinese Dietary Guidelines for Residents (2022)" to actively drink water in small amounts and multiple times. Drinking water can be done at any time of the day, with 1 cup per time and approximately 200 milliliters per cup. Drink one glass of water in the morning and one glass of water in the evening, and drink one glass of water every 1-2 hours during other times. It is recommended to drink at these times: 150-200 milliliters each at 10 pm and 3 pm, which can relieve fatigue and improve state of mind. Drinking 150-200 milliliters half an hour before meals can help control food intake. Drink less 1-2 hours before bedtime, 100-150 milliliters is sufficient to avoid drinking too much and affecting sleep. 3. What to drink? ——White water is king, beware of "sugar coated bullets". White water, mineral water, and purified water are the first choices, as they are additive free, easily absorbed, and can effectively replenish water. Try to avoid sugary drinks such as cola, milk tea, etc., as they not only make you thirsty the more you drink, but also can easily lead to obesity; Excessive consumption of strong tea and coffee can cause diuresis, so remember to drink plenty of plain water after drinking; Functional drinks are only suitable for drinking after high-intensity exercise and do not need to be relied upon in daily life. How to drink? ——Drink slowly in small sips, preferably warm water at 35-40 ℃, which is close to human body temperature and will not stimulate the intestines and esophagus. Avoid drinking ice water or hot water. When drinking water, try to swallow slowly and in small sips. Do not drink it all at once, otherwise it will increase the burden on the stomach, intestines, and kidneys. (New Society)