Different schools of thought exist as to whether or not drinking while you eat is beneficial or harmful to the digestive process. Drinking water before and after you eat clearly aids the digestive process, and according to MayoClinic.com, drinking it while you eat can help, as well. What else you might drink and when you drink it can put a slightly different spin on things. Alcohol and acidic beverages may have a different effect.
Effect on Saliva
The process of digestion starts in your mouth. Chemicals in saliva help soften your food while you’re chewing it, preparing it for passage to your stomach. It’s possible that drinking while you eat might dilute your saliva, but not to such an extent that it would make a difference to your overall digestive process, provided you stick with water. Water helps your salivary glands make more saliva. Conversely, alcohol or any anything acidic, even foods, will dry up the saliva your glands have already produced.
Effect on the Stomach
Once your food reaches your stomach, if there is already liquid there, it will help dissolve your food. Ottawa West Nutrition (OWN) indicates that it’s best to drink before you eat, however, because if you do it during your meal, it may dilute your stomach’s gastric juices. These juices are instrumental in killing any bacteria that might be contained in the food and, with the help of the contraction of your stomach’s muscles, they pulverize your food into a substance your stomach can easily push into the small intestine.
Effect on the Liver
Your liver also requires ample water to do its job properly. Once microscopic food particles pass from your intestines into your bloodstream, your blood will carry these nutrients to your liver. Your liver distributes them to the rest of your body. It decides what to keep for later use and what to pass on for immediate energy, and adequate water is necessary for this process. But the process depends more on adequate hydration overall, not just the water or liquids you give your body while you’re eating.
Although OWN indicates that you should drink half an hour before you eat, MayoClinic.com indicates that drinking water while you eat will not interfere with your stomach’s gastric juices. Not giving your body enough liquids is far harder on your digestion than drinking during a meal. Drinking while you eat can also help “push down” food that you haven’t chewed adequately, but eating that fast and gulping liquid to remedy the problem can result in burping, an uncomfortable buildup of air in your digestive tract or even choking. If you drink with your meal, it's always best to do it slowly and chew thoroughly.