Osmosis

[YT2095]

wasn`t 100% sure if this also belonged in the Evolution/Morphology forum, but it`s more a biological question

 

It`s known that when certain strong smelling "agents" come into contact with the soles of the feet, that they are rapidly absorbed into the blood stream, you may try this yourself as an experiment, get some fresh cut garlic or Vic`s menthol rub and get someone to rub it on the sole of your foot, within about 10 mins, you`ll actualy be able to TASTE IT!

I can understand why underneath our tongues works in a similar way, it`s probably all part of how we absorb nutrients, but FEET???

 

I want to know, what purpose this serves? why did we evolve this way? and does stinky sports shoes effect bad breath?

 

yeah, it`s an Odd question, but I beleive it has merit

[Giles]

if indeed this effect is caused by diffusion*, then it's probably because it wasn't worth while excluding odurants from being absobed through the feet, rather than evolving to cause this. as for the tasting thing, if true, it's just a side effect of the body's ability to move things around very fast, which is obviously handy.

 

*osmosis is the movement of water from a low concentration solution to a high concentration solution; diffusion is the movement of a substance in solution from a high concentration to a low concentration. i find it helps to think of osmosis as "diffusion of water", but the analogy is not exact.

[Guest sciencenerds]

where do you find information on fragmentation and regeneration...?

[YT2095]

c`mon dude, you`ve already asked that once. await your answer, as repeating/flooding won`t get you one any faster!

 

Giles, ok Diffusion it is

I`de still like to know all the reasoning behind WHY it works with feet and it`s purpose, evolutionary or otherwise. as the original post, that effect working under the tongue makes alot of sense, but I can`t get my head `round the feet reason? it`s seems wacky to me

[Dudde]

diffusion it is then;)

 

sciencenerds, await your question's answer in it's original thread, if you can think of a different forum you think it would be best posted in instead of general sci, tell me so. until then, don't spam:-p

 

that's crazy!! I'm gonna go right now and step in some pizza...mmm....gotta pity those who walk around dumps and sanitation plants barefooted all day

[matter]

I think a lot of people have heard that story where a guy with a bunch of LSD is his car gets pulled over by a cop, and he puts it all in his sock and starts to sweat while sitting there. An hour later he is tripping extremely hard. I pretty much thought thas was a rumor.

[YT2095]

Nope it perfectly true it would do that, esp LSD (I don`t know how true the actual story is however).

I`m serious, try rub a fresh cut clove of garlic or Vics vapor rub on the soles of your feet (better someone else do it or wear glove to avoid contamination and false data) I was amazed when I came across it by pure accident, I had a sprained ankle, so my then GF rubbed some Eucalyptus oil into my foot (it was all I had other than chili) about 6 or 7 mins later I had to mentaly backtrack to see if I`de actualy comsumed any by accident, I hadn`t, subsequent experiments with different odours produced similar effects, Fascinating

[Hades]

If it were diffusion, wouldn't this concept work with the palm of a hand or, if it were non-scented, an armpit?

Correct me if im wrong but diffusion is the tendency of matter to move from hi to low concentrations, so why would it be exclusive to the feet?

[Glider]

I thought you were kidding

 

YT2095 said in post #1 :

It`s known that when certain strong smelling "agents" come into contact with the soles of the feet, that they are rapidly absorbed into the blood stream,

 

It's known by whom?

 

 you may try this yourself as an experiment, get some fresh cut garlic or Vic`s menthol rub and get someone to rub it on the sole of your foot, within about 10 mins, you`ll actualy be able to TASTE IT!

 

Could it be simply that, as our skin temperature is around 34 degrees C (which is usually higher than the ambient air temperature), the aromatic molecules are being carried from our feet to our noses in the rising envelope of warm air with which we are each surrounded? The olfactory sense is principal in the sense of taste, not 'taste buds' which only signal bitter, salt and sweet (which is why you can't taste anything when you have a cold).

 

 

I can understand why underneath our tongues works in a similar way, it`s probably all part of how we absorb nutrients, but FEET???

 

Underneath our tongues is lined with a totally different type of tissue to the soles of our feet. Certain substances are readily absorbed through cells that make up the mucous membrane lining the mouth (buccal membrane). Cells of the buccal membrane are nonkeratinized and the intercellular lipids are less structured compared to skin cells, which allows the drug to penetrate easily. As such, it is an effective way of delivering certain drugs in a controlled fashion, whilst avoiding degredation of the drug through first-pass hepatogastrointestinal metabolism (digestion, and breakdown by the liver).

 

The skin on the soles of the feet is very different. It is much thicker, and consists of more robust, keratinized cells and is covered by many more layers of dead, kerotinised epidermal cells than skin elsewhere (even the palms of the hands). Whilst certain drugs can be delivered transcutaneously (e.g. nicotine), even these substances cannot permeate a thick layer of dead kerotinised cells.

 

I want to know, what purpose this serves?

 

If such an effect did exist (and personally, I doubt it), it would have no purpose, in fact it would probably be detrimental. A main function of the skin is to protect our internal environment against toxins and pathogens which exist in the external environment. If substances from the external environment could easily enter our system transcutaneously through the soles of our feet, then walking around in bare feet would be extremely hazardous, and we did that for quite a long time, prior to the invention of shoes.  

[Skye]

I think walking around in most peoples shoes would be at least equally as hazardous.

[YT2095]

Glider, it most certainly DOES exist, and I can`t either work out what possible function it may have... I was kinda hoping you`de know

[VendingMenace]

well, it sounds like you need a control experiment

 

you should take garlic or vics or whatever, put it in a box put your feet in a box and seal it all up, then step on the stuff. Or somehow seal up your nose and mouth away from the garlic or whatever, and get someone to rub it on your feet. Of course you shouldn't know what they are rubbing on your feet, so you are not biased. Then this should be done with other people on this forum and see what everyone comes up with! i mean, jeeze this is a science forum, it seems like instead of arguing about whether or not something happens, we could test it our instead:P

 

of course, first we need to come up with a way to seal feet away form nose and mouth, and a person to rub crap on our feet

[Glider]

YT2095 said in post #11 :

Glider, it most certainly DOES exist, and I can`t either work out what possible function it may have... I was kinda hoping you`de know

 

No, I have no idea. I have never heard of this effect, and as I said before, for the reasons I gave in my previous post (and in the absence of any evidence), I doubt such an effect exists, so suggestons concerning its possible functions would be a bit premature. I have only your word for the existence of this effect, but (though I'm not questioning the integrity of your word), it isn't evidence. Cite your source and I'll look into it. 

 

 

VendingMenace:

 

I think such an experiment would need to involve blood tests. YT stated that "when certain strong smelling "agents" come into contact with the soles of the feet, that they are rapidly absorbed into the blood stream"." You would need to rub the substance on the soles of the feet and then take blood samples at intervals afterwards. This way you would be testing for the presence of an effect, which is easy to demonstrate, simply by finding the substance you are testing for.

 

To tape up the nose, or in other ways isolate the nose and mouth from the feet would mean you would be testing for the absence of an effect, which is extremely difficult to demonstrate. The best you can hope for in this case is an absence of evidence for the effect, which doesn't mean it doesn't exist, only that you failed to find it (absence of evidence is not evidence of absence).

 

The whole experiment would be based upon a contradiction in the original premise though. If the substance is absorbed into the blood, how could we taste it? The orientation of the sensory receptors in the tongue and the nasal cavity denies this (i.e. by facing outwards from an outer membrane, they are facing the wrong way to detect substances in the bloodstream). To taste a substance, it needs to be in solution in the mouth and to smell it, in vapour (airborne) in the nasal cavity (when eating both 'taste buds' and olfactory receptors work conjointly to give the sensation of flavour).

[YT2095]

Well, I shall try find evidence of this on the net for you to look at if possible. I know it sounds lame, but it`s true, my original Source was a TV Docu, and subsequently myself trying it on several different occasions, and it DID work. also I used a second partly to apply these substances, so that I never actualy handled it myself for cross contamination, sox and boots were put on afterwards and when I could smell/taste it on my breath, I did ask the second party and 2 others that popped in for a visit to have a sniff of my breath and asked what smell they could detect, they were 100% right and I never said what the smell was s`posed to be.

OK I know it sounds like weak evidence as a "cite" it would to me also, and I have as yet no further backup, yes you have my word though, it does for some reason work? and Tiger Balm rub is great for it too, you can even get the cinammon type taste as well!

[Glider]

It's not that it sounds lame, many substances have been developed for transcutanious delivery (some of the nastier nerve agents for example). It's that in the absence of any evidence to the contrary, physiology gives no cause to suppose that the soles of the feet are any more effective at absortion than any other part of the body surface. If anything, the mechanisms involved in transcutanious absorbtion viewed in light of the nature of the skin on the soles of the feet, suggest that the soles of the feet are likely to be less effective.

[alt_f13]

Try it with tylonol disolved in water. It doesn't smell but it tastes horrible. And if you use alot, maybe your tongue will go numb

[YT2095]

can`t get that here, I considered Potassium Aluminium Sulphate (bitter alum) as that stuff tastes VILE! only problem is that it`s also a styptic, and may inhibit the absorbtion

and NO... I DONT want any other ideas of vile tasting things thank you