Why do we smell so bad?

  • #27
lisab
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Does your kitty open its mouth slightly, after a http://www.youtube.com/watch?v=Q32E883EQyc"?
I've seen my cat do that after grooming her, um, hindquarters :redface:. Fortunately I knew what it meant, otherwise I'd be perplexed. Seeing a cat do that is a mixture of bizarre and hilarious.
 
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  • #28
DaveC426913
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They do this to bring the odor receptors in the roofs of their mouths to bear.

Humans have them too. Certain odors (such as perfumes) can surprisingly, be smelled in the roof of your mouth.
 
  • #29
Ouabache
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Fortunately I knew what it meant, otherwise I'd be perplexed. Seeing a cat do that is a mixture of bizarre and hilarious.
I have had cats do this and I had the same reaction you did. :smile:
DaveC426913 said:
They do this to bring the odor receptors in the roofs of their mouths to bear.
Are we hinting at the http://en.wikipedia.org/wiki/Flehmen_response" [Broken] response.
I am not surprised we have a similar response. Here's another http://www.youtube.com/watch?v=n1Z6Nz8FuPc" with the Flehmen response.
 
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  • #30
Math Is Hard
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I actually haven't seen her do a Flehmen response in a number of years. She's a very old cat (17) and I wonder if her vomeronasal sensing has gone downhill in her old age.
 
  • #31
chemisttree
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Perhaps it's because old cats don't have much to smile about.
 
  • #32
DaveC426913
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Perhaps it's because old cats don't have much to smell about.
Corrected.
 
  • #33
Unpleasant body odors usually are bacterial products. We sweat, the bugs feed, their metabolic products don't smell good. Fresh sweat doesn't smell so bad; it's the bacterial metabolites that reek.
Correct. This is the response that better answers the question. Your body doesn't by itself stink. It's the bacteria that flock to the moisture on your body that stinks. And because many bacteria are not kind to us, we have an adverse response to this. The fact that people used to go months without bathing and it did not stop them from social and sexual activity may mean that we only now have so many [smelly] bacteria. Sweat that has just come off of you and has not yet had contact with the smelly bacteria has no noticeable smell.
As far as feces and flatulence smelling, this is primarily due to what we eat. I imagine things you eat which cause an excessive amount of methane byproduct will give you smellier farts, because methane by itself stinks.
 
  • #34
Ouabache
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methane by itself stinks.
Actually http://scifun.chem.wisc.edu/chemweek/methane/methane.html" [Broken] is an odourless gas. Perhaps you are thinking of natural
gas of which methane is a large component. In that case a sulphurous
component (e.g. http://en.wikipedia.org/wiki/Methanethiol" [Broken]) is added, which gives its characteristic scent.
 
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  • #35
chemisttree
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Don't forget 3-methylindole, AKA skatole. That's the pure stuff.
 
  • #36
Actually, having lived and worked in the bush for ten and twenty day stints, I know that after about a week, you do not smell anymore. I believe this is because the bacteria and natural oils on our bodies get into balance. Your hair doesn't look or smell dirty. Your face isn't oily. It's quite interesting.

Also, diet has a huge impact on a person's smell. Often with our very acidic diets today, our bodies smell more. I have gone on long juice cleanses to 'reset' my body's systems and clean out my digestive tract. The body stinks badly after three to five days (regardless of how many times you brush your teeth or shower) and then you just don't smell anymore--no coating on your tongue, no need for deodorant. Cool hey?
 
  • #37
Evo
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Actually, having lived and worked in the bush for ten and twenty day stints, I know that after about a week, you do not smell anymore. I believe this is because the bacteria and natural oils on our bodies get into balance. Your hair doesn't look or smell dirty. Your face isn't oily. It's quite interesting.
You still stink, you just get used to it so you don't notice.

Frequent washing actually stimulates oil production, the longer you go without washing, the less oil you produce.
 
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  • #38
Drakkith
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You still stink, you just get used to it so you don't notice.

Frequesnt washing actually stimulates oil production, the longer you go without washing, the less oil you produce.
So if you and a group of people you live around smell for a long period of time, no one notices anymore?
 
  • #39
Evo
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So if you and a group of people you live around smell for a long period of time, no one notices anymore?
You get used to it, as long as it's not changed. That's why people that live in stinky houses don't realize how bad the house and everyone and everything in it smells.
 
  • #40
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If you somehow sterilize your skin with maybe rubbing alcohol and then don't bathe (in a sterile bubble to avoid bacteria) would you avoid BO?
 
  • #41
Evo
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If you somehow sterilize your skin with maybe rubbing alcohol and then don't bathe (in a sterile bubble to avoid bacteria) would you avoid BO?
Since rubbing alcohol won't kill all external bacteria, and under the surface we have more bacteria in glands, mouth, etc... my opinion is no.
 
  • #42
DaveC426913
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If you somehow sterilize your skin with maybe rubbing alcohol and then don't bathe (in a sterile bubble to avoid bacteria) would you avoid BO?
And there's bacteria on everything you touch including the air you exist in. If you wipe out bacterial cultures on your body, you provide a very fertile virgin soil in which all sorts of hazardous things can take over.

To be clear: the non-harmful bacteria on your skin provide hefty competition against the invasion of more harmful types that would be happy to feed on your skin waste products.

This can be very bad. It happens in the stomach and colon, when harmless or even beneficial bacteria get purged, and some very nasty bugs can get a foothold, making you very sick and possibly dead.
 
  • #43
Ryan_m_b
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If you somehow sterilize your skin with maybe rubbing alcohol and then don't bathe (in a sterile bubble to avoid bacteria) would you avoid BO?
Skin flora is a necessary component of your body and provides not only protection in the form of competition with harmful bacteria but also stimulates your immune system. The latter is paramount, being too clean especially in childhood is hypothesised as causing allergic diseases in later life.
 
  • #44
turbo
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Have you ever gone hiking-climbing with a member of the opposite sex? You're going to both get a bit fragrant with the exertion. That should not be a problem, if you are a normal person. In fact, you might find a new obsession.
 
  • #45
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Love is in the air, at least it smells like it. :smile:
 

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