The digestion process starts in your mouth. Water helps dissolve and break apart the food while you chew, allowing your saliva to start breaking down the food into manageable pieces. Water then helps wash the chewed food down into your esophagus. Rather than interfere with digestion, drinking water after eating continues to aid your digestive system.
Drinking water after a meal improves your digestion. It takes your body a while to break down the food you eat, so drinking a large glass of water immediately after eating can help dissolve food and transport it through your digestive tract. Eating a diet that contains plenty of fruits, vegetables and whole grains also improves your digestion. In addition to containing water, these foods also contain fiber, which adds bulk to your stools and helps them pass through your digestive system smoothly.
Swallowed food passes through your esophagus, which uses a wavy motion to squeeze the food toward your stomach. The process takes roughly two to three seconds. Once it reaches your stomach, the food breaks down further as water helps it dissolve and your stomach churns and mixes the partially digested food to break it down into smaller pieces. This allows the mixture of gastric juices and water to penetrate throughout the food. Water does not dilute gastric juices.
The food then passes through your small intestine, which removes vitamins, proteins, minerals, carbohydrates and fats. At this point, water helps lubricate the digestive tract to ease the passage of the food. The process might take as long as four hours. At the end, all that remains is a thin, watery mixture that passes into the large intestine, which removes the last of the water and some remaining minerals before excreting whatever is left over as waste. After aiding in digestion, the water you drank after your meal now hydrates your body.
Drinking water after eating also helps you control your appetite. For example, if you’re on a diet, you might feel hungry after eating. Drinking a large glass of water after a meal creates a sense of fullness, which might help stave off cravings for more food. Drinking water before and during your meal also contributes to fullness and helps you keep your calorie intake low.