Science, Art, Litt, Science based Art & Science Communication

There are no master races

Q: I saw a You Tube video in which a doctor says the sweat of Korean and Japanese people doesn't smell. Is this true?

https://www.youtube.com/watch?v=SNsc5aTBJhw&t=77s

Krishna: I clicked on the link you sent and watched the video. I think this doctor didn't put things properly.

Let me explain. There are no absolutes.

These people you mention do smell!

But South Koreans and Japanese tend to have lesser body odour than people from other regions.

Japanese and Korean people do sweat, but some have a genetic makeup that reduces the production of odorous sweat:

The secret behind the lesser body odour among South Koreans and Japanese lies in a gene called ABCC11. It is responsible for determining the type of sweat our body produces. There are two main types of sweat glands: eccrine and apocrine. Eccrine glands produce a watery, odourless sweat, while apocrine glands secrete a thicker, more odorous substance.

The ABCC11 gene reduces the activity of apocrine glands, which are responsible for producing strong-smelling sweat in the armpits and groin. According to research from the University of Bristol, only 0.006% of Koreans have the ABCC11 gene, which is a much lower percentage than in other populations.

The ABCC11 gene controls the function of apocrine glands. A specific variant of this gene, commonly found among East Asians, reduces the production of smelly sweat by limiting the activity of apocrine glands. According to scientific research, around 80-95% of Koreans and Japanese possess this gene variant. In contrast, only about 2% of Europeans and 3% of Africans possess the same variant. This genetic difference helps explain why people from South Korea and Japan tend to have lesser body odour.

To understand why the ABCC11 gene affects body odour, we must delve into the science of sweat. When we sweat, it’s not just water being released; there are also salts, proteins, and other compounds. Body odour arises when bacteria on our skin break down these compounds, releasing smelly substances in the process.

The apocrine glands, which are primarily found in areas like the armpits and groin, produce a sweat containing more proteins and lipids. These compounds are a veritable feast for bacteria, leading to a stronger odour. However, people with the ABCC11 gene variant have less active apocrine glands, thus producing less of the sweat that causes body odour.

It’s essential to note that genetics isn’t the only factor influencing body odour. Personal hygiene and cultural practices also play a crucial role. South Koreans and Japanese place a strong emphasis on cleanliness, with daily bathing and frequent use of personal care products.

But it seems they don't use much deodorant.

Q: My Korean classmate said Koreans are the real master race, because they're the only humans without body odor. Is that true?

Krishna: There aren’t any “master races”. The master race is a pseudoscientific concept in Nazi ideology. True science doesn’t endorse it.

There are no absolutes.

These people you mention do smell!

But South Koreans and Japanese tend to have lesser body odour than people from other regions.

Japanese and Korean people do sweat, but some have a genetic makeup that reduces the production of odorous sweat:

The ABCC11 gene reduces the activity of apocrine glands, which are responsible for producing strong-smelling sweat in the armpits and groin. According to research from the University of Bristol, only 0.006% of Koreans have the ABCC11 gene (1), which is a much lower percentage than in other populations.

The ABCC11 gene controls the function of apocrine glands. A specific variant of this gene, commonly found among East Asians, reduces the production of smelly sweat by limiting the activity of apocrine glands. According to scientific research, around 80-95% of Koreans and Japanese possess this gene variant. In contrast, only about 2% of Europeans and 3% of Africans possess the same variant. This genetic difference helps explain why people from South Korea and Japan tend to have lesser body odour.

To understand why the ABCC11 gene affects body odour, we must delve into the science of sweat. When we sweat, it’s not just water being released; there are also salts, proteins, and other compounds. Body odour arises when bacteria on our skin break down these compounds, releasing smelly substances in the process.

The apocrine glands, which are primarily found in areas like the armpits and groin, produce a sweat containing more proteins and lipids. These compounds are a veritable feast for bacteria, leading to a stronger odour. However, people with the ABCC11 gene variant have less active apocrine glands, thus producing less of the sweat that causes body odour (2).

But it seems they don't use much deodorant, because they don’t need it.

Footnotes:

Deodorants: do we really need them?
‘Dependence of deodorant usage on ABCC11 genotype: scope for personalised genetics in personal hygiene’ by Santiago Rodriguez et al is published today [17 January 2013] in the Journal of Investigative Dermatology, (Nature Publishing), doi:10.1038/jid.2012.480