After meal, you are always advisable to have a gap for atleast 15-20 minutes even before drinking water. Thge logic behind this is, when you start eating your food, digestive juice starts to secrete for digestion and if you drink water in betwwen, this will dilute the digestive juices and you may face problem in digestion.
Specialists usually suggest to have any fluid atleast 30-45 minutes before and after your meal.
When the questions comes to Soda, I do not think that it is good your normal digestion and it must not be cool as cold drinks after meals allowed the fats to freeze down in your food vessels.Doctors suggest to have a lime water/leuk warm water after meal for good digection. Lime gives acid for fats digestion and warm water helps to moves the ingested food ahead for digestion.
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