A lot of Chinese believe that drinking cold beverages with food will solidify the fats and oils and kill you. Cold drinks will give you a cold stomach and kill you.

Add to that the necessity to boil water to purify it ergo warm/hot means "clean."

When asked, usually I get blank looks, or something along the lines of, "No why". Sometimes, there's mention of "Chinese bodies". For the most part, I don't think Chinese understand why they do it, just that it's tradition, and so they do it.

I'm not sure the actual reason, but could be due to people not being as sick when drinking water that has been boiled in the past (and present, for that matter, given pollution), and basing tradition around it, without understanding why it worked. Rather than make the connection with boiling killing germs, it just became accepted that "drinking hot things is good", and was enshrined in tradition.

Luke warm beer is so bloody awful.

here in Shenzhen the shops turn the fridges off (winter time)its not even cold in Shenzhen in the winter.

At that point I think the most logical theory is the Time Travel Troll: someone somewhere invented time travel, went several hundred years back, taught the Chinese about hot water, open windows, TCM, walking backwards, clapping hands in public... and now here is shiny Modern China. Oh, nice prank.

That's the only way it makes sense anyway.

ugh.  lukewarm beer.  too cheap to run the fridge.  and if u think about it, fridge is a pretty new idea to most of 'em.  warm beer sux!

In Canada of yore, there was a freshly arrived pilgrim family preparing for the winter. The husband and father set upon cutting enough wood for the winter.

The man asked the old Indian next door how cold the winter would be. The wise old Indian told the young pilgrim that the winter would be mild.

After a week of intense work, the young man came back to the Indian, and asked him if he cut enough wood to go through the winter. The Old Indian told him that would not be enough, as the winter will be quite cold. Trusting the wisdom of a man who went through dozens of winters, the young man went back to his wood cutting chore.

After a whole month of arduous work, the young man came back to the Indian, and asked he cut enough wood to go through the winter. The Old Indian told him that would not be enough, as the winter will be extremely cold.

The young man was tired and quite angry at the old Indian man. Was he playing tricks and jokes with him ? He asked the Old Indian
"How do you know the winter is going to be this cold ?"
"Old Indian saying goes like : the more the White Man cut s wood, the colder the winter will be"

I believe a similar logic is at work with that cold & hot water thing.

It can be connected with the history. When Europeans came to China so they realized the Chinese fall much less ill in comparison to them. 

The main reason for this was a hygiene routine at that time almost unknown in Europe but practiced by big part of China population.

Another part was drinking boiled water or tea (using again boiled water) which killed majority of the bacteria.

As during the 20th century the huge parts of Chinese society did not have the access to safe water so they just went on in the traditional way to their own benefit.

On top of that it looks that drinking the warm water is really better for the organism,

never will understand it clearly. Ok, let they do as they want, but what I do with my body shouldn't be their concern. And what worse, telling and forbiding my son to drink his small cup of slightly cold coke, after eating cake on his own birthday celebration and forcing him to drink hot water, which he hate same as I do. In his home, by people invited to visit and eat and drink ... that's over my acceptance level... 

 I have always pushed a bit my wife to make some friends , and but we find out that every one act like an idiot - asking you everything personal, telling you that your decisions are wrong and that you have to dress your son in four five layers of clothing because is only 16 degrees outside ...