Your meal is full of sauce or spicy food? You might be thirsty, but never drink water after a meal! Two reasons if you're asking why.
When you drink cold water after a meal, you're forcing your metabolism to speed up. Why? To heat the cold temperature entering you body. This heating takes away the energy needed for digestion. You body requires a significant amount of energy to break up the food you eat saving the nutrients and eliminating the waste!
When you drink water after or during your meal, it decreases digestive enzymes and stomach acids. This weakens food break-down and causes digestive problems.