Name: 日本人為什麼不臭! (Why Japanese don't smell!)
Uploaded: 2021-01-14T06:26:02.000Z
Duration: 4 min 11 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

Hey guys! One of the biggest problems you hear foreigners talk about in Japan is their

lack of a deodorant selection. There are all kinds of rumors about why Japanese people

轉承詞

don't have as much body odor as us stinky foreigners. You'll hear that it's because

we foreigners don't clean ourselves, unlike Japanese people who often take a full bath

every single night. You'll hear that it's because of our diet and our love of dairy

and meat products. Or you'll hear that it's because Japan is a magical land where when

you step off of the airplane, suddenly you don't need to wear deodorant anymore.

But like most mysterious questions, the actual answer lies in SCIENCE. To understand this,

you need to know where body odor comes from. We have two primary types of sweat glands.

Eccrine and apocrine. Eccrine sweat glands are small and found almost everywhere on the

body. As you can see from this picture, they go directly from underneath your skin, to

your skin's surface. They secrete a mixture of water and salt, and this is used to cool

down your body. But then we have apocrine sweat glands. And

these are the glands that cause body odor. These glands are larger and are only found

in certain areas of the body, primarily your underarms and pubic region. Instead of secreting

directly onto your skin, they secrete into a hair follicle, which then carries the sweat

up onto your skin. And these glands secrete primarily proteins, lipids (which are things

like fatty acids), and steroids. By itself, this sweat does not smell. However, it IS

a delicious and desirable substance for the bacteria that live on our skin. Bacteria feed

off of this sweat, metabolize it, and then their waste products are what smell. So, body

odor essentially comes from bacteria poop. This is also why if you want to prevent body

odor, you should be looking for a deodorant that makes your underarms an inhospitable

place for bacteria to live. Different bacteria and the different enzymes

they use to break down our sweat produce different smells, which is why different people have

different body odors. So then what makes Japanese people have less

body odor? Genetically, they have fewer of these apocrine sweat glands. Why? That's not

fair? How does that happen? Why do I have to be more smelly? It all comes from one specific

gene: ABCC11. There are two variations of this gene. One with the allele A, and one

with the allele G. People born with the G allele have more active apocrine sweat glands.

Whereas peopleborn with the A allele have fewer active apocrine sweat glands, and little

to no body odor. The smelly allele G appears to be the original version of the gene, whereas

the non-smelly allele A appears to have emerged approximately 2,000 generations ago.

Why did the A allele appear? We don't really know, but we think it might have something

to do with colder climates. Here you can see a chart of what percentage

of different races have which allele. So most of us who are African, Latin American, European,

or Pacific Islander have the smelly version of the gene. However, only about a quarter

of Japanese people, less than 10% of Chinese people, and pretty much no Koreans have the

smelly version of the gene. But, there's more to this gene than just whether

you produce body odor or not. There's a type of apocrine gland in your ear canal that produces

ear wax. As many of you may have heard, Japanese people typically have something called dry

earwax, which is flaky, unlike our earwax, which is wet and goopy. The type of earwax

you have is also determined by the version of gene ABCC11 that you have. So, if you have

the G allele version, you will have wet earwax, and if you have the A allele version, you

will produce dry earwax. So that is a very quick way to check which version of this gene

you have, and whether or not you're likely to have much body odor.

In conclusion this is why most Japanese people don't smell as much and why they don't have

as large a variety of deodorant as we have. So, just because you move to Japan, that doesn't

mean you can magically stop using deodorant. I have a video coming up soon where I will

show you different types of Japanese deodorants, and which ones work best for us smelly foreigners.

Thanks for watching guys! I'll see you later.