Is it necessary to drink when you eat to digest well? And, if so, better during or after meals?
He answers Andrea Ghisellidirector of the 1st level Master in Food Science and Applied Dietetics, Unitelma Sapienza, Rome (GO TO THE FORUM)
The belief is quite widespread, often induced by too many visits to non-institutional websites, that drinking during meals is harmful because the dilution of gastric juices would lengthen digestion times. But there is none of it true and it is one of the false beliefs also reported in the “Italian guidelines for healthy eating”. Water is in fact essential for proper digestion of food and for the absorption of nutrients. Starting the path of food from the oral phase, water is necessary both for correct chewing and to facilitate swallowing. This task is entrusted to saliva and it is advisable to drink just to make the body water and promote proper salivationas well as to cleanse the mucous membranes and palate.
Water dilutes gastric juices, but these are specially secreted in the right quantity to be diluted, so as to allow the solution and therefore the continuous mixing with the digestive enzymes which will best attack the food components, making them suitable for absorption. Even when partially digested food leaves the stomach and reaches the intestines, water is needed for both continued digestion and nutrient absorption. A right amount of aqueous solution can in fact be more easily distributed over the entire surface of the intestine dedicated to the absorption of nutrients. Water is also important for the progression of digested food throughout the intestinal tractas well as to give volume and the right consistency to the feces.
In addition, water has a function on the sense of satiety. In fact, satiety can be induced both by chemical stimuli (composition of the meal) and by physical stimuli (distension of the gastric wall), which together give the signal that we have eaten enough. The distension of the walls of the stomach, determined by the increase in volume of its contents by water, is able to contribute to satiety and it is therefore important to drink during meals also as a strategy for weight loss, even if obviously we cannot rely on water alone. It is therefore advisable to drink water (and only water) during the meal, in small sips, starting with the first bites. This will improve chewing, swallowing and digesting foodas well as giving the right sense of satiety.