Contrary to popular belief, drinking water during or immediately after a meal is not harmful at all.
However, in some cases it still makes sense to consume drinks and liquid foods separately from solid foods.
Firstly, people suffering from reflux and heartburn are advised to completely separate drinking from eating.
In this case, you need to drink half an hour before or 2 hours after eating.
Secondly, drinking liquids separately from solid food is useful in the treatment of diseases caused by helicobacter pylori.
Thirdly, not drinking anything with food can reduce the intensity of nausea during pregnancy.
In other cases, you can drink during and after meals, but water, not tea or coffee. They impair the absorption of iron from food.