This is a very good article. For those who like to drink cold water, this article is applicable to you. Not only about the warm water after your meal, but about heart attacks.

It’s a normal practice to drink water during or after meals. Different schools of thought go by different philosophies. Some suggest not drinking water during or after meal is not advisable as it dissolves enzymes and acids that are secreted to help digestion. Drinking water 15-20 minutes after meals is considered ideal.

Some people who are dieting believe in drinking several glasses of water a little before meals. It reduces hunger and as a result the amount of food we would otherwise have eaten. Many such theories are doing the rounds all the time basically encouraging healthy life free of diseases and complications.
Some people like to have a cup of cold drink. It is nice to have a cup of cold drink after a meal. However, the cold water will solidify the oily stuff that you have just consumed. It will slow down the digestion. Once this "sludge" reacts with the acid, it will break down and be absorbed by the intestine faster than the solid food.

It is best to drink hot soup or warm water after a meal.

This is one such suggestion that promotes drinking hot water during and after meals.
On doing a survey it was found that French and Japanese women follow this. The Chinese and Japanese drink hot tea with their meals…not cold water, maybe it is time we adopt their drinking habit while eating.
Drinking hot water after meals reduces cancer risk.
Let me explain how.

Drinking cold water will solidify the oil part of the food we have eaten. This will slow down the digestion process. And when this sludge reacts with the digestive enzymes and acids, it will break down and will start getting absorbed by the intestine faster than the solid food. This lines the intestine. The consequence is that this will turn into fats and lead to cancer. Therefore it is best to drink hot soup or warm water after a meal.

Cold water can also in extreme circumstances lead to heart attacks. As we have our meals enzymes and acid secretions start and this process sort of warms up the body. Drinking cold water is like attacking the body with an exactly opposite temperature. Not only does the whole procedure of digestion gets interrupted or slows down, the body can also react in the form of a heart attack. It does not always come after a pain in the right arm or pain in the chest.

A serious note about heart attacks - You should know that not every heart attack symptom is going to be the left arm hurting. Be aware of intense pain in the jaw line.

You may never have the first chest pain during the course of a heart attack. Nausea and intense

sweating are also common symptoms. 60% of people who have a heart attack while they are asleep do not wake up. Pain in the jaw can wake you from a sound sleep. Let's be careful and be aware. The more we know, the better chance we could survive.

So warm water is the way to go to keep off cancer. It makes sense and it doesn’t cost anything. Just calls for a change in habit. In the beginning hot water doesn’t taste good but that’s simply because we have never had hot water as a routine. Once we get used to it feels fine.

Reference:

http://www.healthoma.com/a-glass-of-hot-water-after-meals-reduces-cancer-risk/