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Mucus and other such fun

  1. Jul 31, 2007 #1
    Why is nasal congestion due to a cold so much worse inside than outside? (Or is it just me?)
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  3. Aug 1, 2007 #2


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    Having noticed a similiar effect, I have a theory about that.
    I have both chronic bronchitis and advanced emphysema, and I find that I can breathe much easier in cold weather. Having been something of a racer back in the day, I can't help but suspect that it's based upon the same principle as a car running better in cold or foggy air. It's a denser intake charge.
    A 'normal' person with nasal congestion is sort of in the same predicament that I am all of the time, in that inhalation is difficult. Warm air takes up more space per molecule than does cold air. In made-up numbers, rather than actual figures, let's assume that your lungs hold 1 litre of air each. With cold air, you might have something like 30% more molecules (and therefore 30% more oxygen) per breath than you do with warm air. As a general rule (at least where I live), it's warmer inside than outside.
    Also, in an enclosed environment the air will have a lower percent of oxygen since carbon dioxide will accumulate without the benefit of free circulation.
  4. Aug 1, 2007 #3
    Interesting... But I've noticed this effect both in the winter (colder inside than outside) and in the summer (warmer inside than outside). The cross-seasonal effect also leads me to believe it ain't allergies.
  5. Aug 1, 2007 #4


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    In that case, I'm stumped for now.
  6. Aug 1, 2007 #5


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    Could be something inside that you are allergic to.
    That wouldn't be affected by seasons.
  7. Aug 1, 2007 #6


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    Good point. Among my other maladies is an allergy to dust. Doesn't matter what kind of dust, from house stuff to road dirt to crap that flies up when I mow the lawn. It isn't seasonal.
  8. Aug 2, 2007 #7

    jim mcnamara

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    If this helps -

    Elevated physical activity levels - like going from sitting to walking - can open up clogged nasal passages. So, if while out you are mostly walking that may be a contributory factor.

    And, in general, the overall allergen load inside is generally higher than outside. Dust/skin mites, shed skin, are found inside very commonly. Pollutants from cooking - the products of the destructive distillation of low molecular weight fatty acids during cooking for example - are also something many people have problems with. Deep fry a lot?
  9. Aug 2, 2007 #8


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    I have noticed the same effect when I had a cold a few weeks ago. Inside my nose would become totally congested, outside the passages would clear almost completely. I haven't come up with a theory yet that would explain this effect.
  10. Aug 2, 2007 #9
    I get the same effect with my allergies to pollen, but it may not be related since the quality of the air is better outside. For the other conditions, there may be some hints here:


    Maybe the temperature outside is lower and this reduces the size of the blood vessel? If not lower, there is a lot more air (as it moves/blows) to transport away heat content?
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