Do Chinese have straight intestines, and foreigners wiggly ones?

I recently held a small party.

The adults sat in the kitchen and - while the children wrecked the rest of the flat - I offered one of them a cold beer.

I knew the answer would be no from the Chinese contingent, because Chinese people usually refuse to consume cold liquids, believing they will harm their stomachs and give them diarrhea.

Appearing to strengthen this belief, one of my neighbors testified that she had just read a report that said where "foreigners" have wiggly intestines, while Chinese intestines are straight, and it is this difference that makes it impossible for Chinese people to consume anything cold. What is consumed, she explained, gets to their stomachs faster along their straight intestines - rather like a scary steep water slide, as opposed to a more gently sloping spiral one.

I was floored by this. She appeared to believe that Chinese people are made differently from foreigners. Do Japanese people have straight, or wiggly intestines? I asked. What about people from the Middle East?

I always raise queries like this in response to claims or questions about foreigners, because I always find it incredible how we are all assumed to have identical tastes, customs and behaviors, regardless of whether we come from Moscow, Rio de Janeiro or Texas.

That leads me to the other problem with what she had read. By the time food or liquid reaches the body's digestive tract, it has already been in the stomach, warmed and mixed up. Therefore, the speed at which it passes through the intestine will have no effect on how quickly it ends up in the stomach. Quite simply, it has already been there. That's unless, of course, our internal organs are upside down as well as shaped differently.

It's not just a diarrhea problem. It has implications for weight loss, too. This, taken from a Chinese health website: "According to traditional Chinese medicine if you drink cold drinks after a meal (especially a big one), the cold fluid will solidify anything fatty in your stomach, making the fat harder to pass.

"Second, if you are a woman, cold drinks are especially not for you. Since the female body will protect the uterus from being cold, if the stomach is cold internally, the body will accumulate more fat near the stomach to keep it warm. In other words, even a thin girl could have a big tummy if she often consumes cold drinks."

I failed to find any Western science materials that backed this up, although I did find some other frightening TCM advice that suggested drinking cold liquids could give you cancer.

My colleague Zhi Jia studied in Germany for a few months.

"It's really strange," she said. "When I lived in Germany I could take drinks straight out of the fridge and drink them with no problem. But as I soon as I came back to China, I couldn't do it."

I asked her if she had actually tried or had just fallen straight back into the belief that had been handed down to by her parents. She couldn't remember.

Is it just a psychological thing or does it have some basis? My neighbor swears blind that one sip of cold water will send her to her sickbed.

We roll our eyes, but perhaps it is to do with the fact that in the past, cold water carried diseases like cholera, so it simply was not safe to drink unless boiled.

Now I don't care what people choose to drink. If they prefer to drink tepid water, that's fine. I just feel sorry for them missing out on that wonderful feeling of slaking the thirst on a parched hot day with a huge gulp of ice-cold fresh lemonade.

It also means that for my next party, I now have a safe hiding place for my best wine. The fridge.