I figure, after dipping our toes into the darkness of TCM in the last few weeks, it was a good time to take a step back and touch on something a little warmer. Specifically, warm water. But first, if you haven't had your mind blown by how ridiculous Traditional Chinese Medicine is, here are the last 3 episodes:

• Eating placentas and drinking children's urine

• Misinformed about miscarriages (damn. Good title, too late)

• Human penis, pubic hair and poo tea

The hot water myth

Unless you've been to China you will probably be unaware of this odd phenomenon, but the Chinese believe that drinking straight, hot water is good for your, and us broken, corrupted westerners should not be drinking iced water no matter how hot the day.

This has oftentimes been the bane of my life, when it's a hot, 40C summer's day and you can't go to the nicest of restaurants and get a cool glass or jug, having instead to resort to hot water, or beer.

The belief here is that cold water causes cancer and cramps, whereas hot or warm water wakes up your digestive system, increases blood circulation, detoxifies your body and reduces cramps. Whether you're on your period or you got your feet wet in the rain, sore throat or bad sleep, hot water is the answer.

Historical viewpoint

Naturally, this fantastical idea has a point of origin. Back in the day, or 'in ancient times' I suppose at 400BC, hot water was something of a luxury, and ice was even more of a luxury with the notable lack of freezers.

However, scholars of the past were a lot more savvy than those of the modern day and simply considered both hot and cold water as something un-special in and of themselves. They basically concluded that hot water would warm your body up and cold water would cool it down. Fascinating.

Of course, for the plebs among China, being too hot was less troublesome than freezing to death so there was a lot of emphasis on keeping warm, reserving any hot water they could generate for the weak, elderly and pregnant. Meanwhile, royalty would enjoy the iced drinks when it suited them, since they'd just sent a special team of slaves or servants up north to get some.

To help rumour spread, a cholera outbreak hit Shanghai when 1.5 million refugees flooded in after the Taiping rebellion in the 1860's (a story for another post), and noting that the problems were spreading north and not south, everybody jumped on the fact that the wealthy southern half of China drank more hot water, even though the actual reason for the spread turned out to be boats shipping deliveries up north, not south.

So there's no historical foundation to stand on here, but what does Traditional Chinese Medicine say?

The 'Philosophy'

Well, later on there was a public guideline release for people rightly informing them that boiling water kills off the bacteria, preventing such horrible epidemics from reoccurring. But the horrible, horrible Mao era spread the idea more arbitrarily (See first post on Mao's historical role in TCM.

Nowadays TCM took over this idea and nonchalantly threw the idea of Qi onto it. Because Hot is opposite of Cold, therefore there's a 'balance' aspect... Yin and Yang! Totally makes sense and therefore is definitely true!

You see, in Chinese Medicine and more general belief practice, hot and cold are not necessarily regarding physical temperature.

• 上火 (Shang Huo), or 'on fire' is a medical state of too much 'yang' and not enough 'yin'. Your energy is too masculine. This supposedly causes things like heartburn, inflammation, fever or other hot-type ailments.

• 着凉 (Zhao Liang), or 'taking cold' is, naturally, too much yin, not enough yang - your energy is too feminine (because again, boy is opposite to girl so it totally makes sense). You can probably guess some of these ailments; flu, cold, cold feet/bad circulation... you get the idea.

So it's not a stretch for TCM advocates to jump on the similarity between temperatures, metaphorical and literal, to conjure up some medical routine.

The Science

Though these beliefs can be solved with common sense (Water doesn't remain cold after drinking it), I'd like to dig deeper anyway.

I think it's fair to say that water has a lot of health benefits, regardless of what 'western' or eastern medicine says. Drinking water tends to keep one alive, for a start, but a nice steamy bath or shower can work wonders to relax you, open up your blocked nose and so much more. That's no mystery.

But there are many unforeseen problems that I'd love to go into:

Hot Water

It turns out that hot water can cause cancer! Hear me out. In a press release by WHO (World Health Organization), it was reported that, during a study looking at potential carcinogenic properties of coffee, they found that the water itself can cause cancer of the oesophagus, if sufficiently hot enough to burn the throat and damage the tissue (at or above 65°C - a hot cuppa). Coffee was fine, though.

But ok, cancer is mostly out of sight out of mind, who cares, right? But very real issues arise in our daily lives. In more developed countries and cities, drinking from the tap is typically safe, cheap and tasty. But even here in Shanghai, tap water is a big no no. To make matters worse, hot water actually increases health risks as the hot water increases the rate contaminants like lead and copper being dissolved, due to the higher energy in hot water.

If nothing else, you might burn your tongue, and if you burn your tongue, you're probably burning your innards, too.

Now, although hot water can indeed improve menstrual cramps and so forth, so can cold water, or just water in general. There's no evidence I can find that cold water can cause any cramp issues or otherwise. If anybody has found some feel free to post it in the comments where I can pick it apart. However:

Cold Water

There are some issues with cold water. For example, cold water can make your nasal mucus thicker, according to a single study of just 15 people. Damn.

Cold water can actually cause cancer too after a hot meal, becau-- oh wait that's a myth, too.

More seriously, people already suffering from migraines may see migraines triggered from the consumption of cold water. Otherwise, that's it really.

Like with @haejin's predictions, people are quick to forget things that don't confirm their beliefs, and quick to remember those that do; it was that evil glass of cold water I had 3 days ago.

So...

You'd think at this point if cold water had an effect, people would have noticed around the world by now, not just in China. Unless of course, we're implying the Asian race is inherently weaker and can't handle a glass of cold water? Even so, this is a kind of God of the Gaps argument, forever searching for that unfalsifiable point that you can stand on victoriously.

And if you really are seeing a correlation, it's likely because you have learnt to believe it. Placebo. Again.

Alright that's it for now. I might take another dark turn in next week's episode. There's a lot of darkness in TCM, after all. Thanks for reading!

All Images CC0 Licensed

References: _{IARC Monographs evaluate drinking coffee, maté, and very hot beverages
| Cold water is not cancerous | Cold water is poisonous! Note how this website is quick to sell you related products | A very small study showing a very benign benefit of hot water that we already knew | Hot & Cold Chinese Philosophy | Hot water history}