During sleep, the body continues to lose water — particularly through breathing and sweating. Therefore, gastroenterologist Lisa Ganjhu from NYU Langone Health recommends drinking water soon after waking up, as reported by Verywellhealth. Even moderate dehydration can affect well-being, concentration, and decision-making ability. However, there is no need to overload on water in the morning. Nutritionist Ethan Balk believes that starting with **about 240–470 ml of water** is sufficient. ### Water First, Then Coffee This sequence may have another advantage — for the digestive system. Water promotes the normal functioning of the gastrointestinal tract. Warm water can stimulate bowel activity and may help some individuals with morning bowel movements. Additionally, a glass of water before coffee can reduce discomfort that some experience due to the acidity of the beverage. However, this varies from person to person. Some people have been drinking coffee on an empty stomach for years without any unpleasant sensations. For others, coffee on an empty stomach can provoke **heartburn, acid reflux, or a feeling of acidity and discomfort in the stomach**. ### Does Coffee Dehydrate? Moderate coffee consumption does not necessarily mean that a person needs additional water. According to Balk, **one to three cups of coffee a day** is a normal amount for many people. It is much more important not to limit oneself to just one glass of water in the morning but to ensure adequate fluid intake throughout the day. Proper hydration is essential for digestion, physical activity, concentration, and overall well-being. ### How Much Water Do You Need in a Day The article cites recommendations from the Academy of Nutrition and Dietetics in the U.S.: women should aim for about **11.5 cups of fluid per day**, while men should aim for about **15.5 cups**. Individual needs depend on diet, physical activity, air temperature, and other factors. So, it is not necessary to replace coffee with water. One can simply change the order: drink a glass of water after waking up and then enjoy the usual cup of coffee. For some people, this simple morning habit can indeed make the start of the day more comfortable.
