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Dirt may explain why richest countries suffer diseases rarely seen anywhere else

smithsonianmag.com

31–40 of 62 posts

Re: Dirt may explain why richest countries suffer diseases rarely seen anywhere else

#31
post #6

The article reports an interesting observation: "Still, the 500-mile boundary between Finland and this Russian republic marks one of the steepest standard-of-living gradients in the world: Finns are seven times richer than their neighbors across the border. 'The difference is even greater than between Mexico and the U.S.,' Knip tells me." Then the article gets into the main point: "Soon, studies from around the world…

I find the "Old Friends" hypothesis a good answer for why hygiene causes allergies: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1774411/ The basic idea is that the human immune system has co-evolved with a number of immune suppressing parasites. Hygiene has greatly reduced the number of these parasites we're exposed to and without them the human immune system is too reactive. That extra reactivity results in our immu…

Interesting. Could that be why people with overprotective mothers (often "indoor kids", nerds) tend to have allergies? As infants their cribs and highchairs were meticulously kept clean and sterile with disinfectant wipes.

Re: Dirt may explain why richest countries suffer diseases rarely seen anywhere else

#32
post #24

I can buy trying to figure out allergies, but Type I diabetes? It's clearly hereditary, rarely showing up without some family link. Finland may have a high rate due to a lack of ethnic diversity.

Hereditary, but not in a strong sense - to quote the american diabetes association:

> In general, if you are a man with type 1 diabetes, the odds of your child getting diabetes are 1 in 17. If you are a woman with type 1 diabetes and your child was born before you were 25, your child's risk is 1 in 25; if your child was born after you turned 25, your child's risk is 1 in 100.

Even if both partners are diabetic, the risk is only 1 in 10 to 1 in 4. This strongly implies that what is heritable is the vulnerability to getting diabetes, rather than getting diabetes itself. There is, presumably, some trigger that also needs to occur.

Re: Dirt may explain why richest countries suffer diseases rarely seen anywhere else

#34
post #28

I'm surprised that the article didn't touch on differences in childhood mortality rates. The theory proposed has always made a lot of sense to me. However, I would expect any reporting on the topic to consider the extent to which the allergy-sufferers amongst us (such as myself) made it through childhood because of better early childhood medical care, thus skewing the later-in-life allergies and autoimmune disease st…

That seems obvious, however AFAIK infant mortality is not much higher in eastern Europe and Russia than in the west, so this probably doesn't apply there.

Re: Dirt may explain why richest countries suffer diseases rarely seen anywhere else

#35
post #28

I'm surprised that the article didn't touch on differences in childhood mortality rates. The theory proposed has always made a lot of sense to me. However, I would expect any reporting on the topic to consider the extent to which the allergy-sufferers amongst us (such as myself) made it through childhood because of better early childhood medical care, thus skewing the later-in-life allergies and autoimmune disease st…

In 2011 under-5 mortality (m/f):

Russia 18/14 per 1000

https://www.amnesty.org/en/region/russia/report-2011

Finland 5/4 per 1000

https://www.amnesty.org/en/region/finland/report-2011

Re: Dirt may explain why richest countries suffer diseases rarely seen anywhere else

#36
post #28

I'm surprised that the article didn't touch on differences in childhood mortality rates. The theory proposed has always made a lot of sense to me. However, I would expect any reporting on the topic to consider the extent to which the allergy-sufferers amongst us (such as myself) made it through childhood because of better early childhood medical care, thus skewing the later-in-life allergies and autoimmune disease st…

I wondered the same thing. As a follow-up to wazoox's comment, I looked into the mortality rates of the areas for the studies.

I couldn't find the infant mortality rates of Petrozavodsk, so I went to region (Republic of Karelia) instead:

Infant mortality rate of Karelia in 2000 [1]: 14.4 %

Of Finland: [2] 2.6 - 4.5 %

So at a 3-7x higher incident rate, infant mortality does seems like a reasonable hypothesis. I wouldn't jump on the one-explanation-covers-it-all stance though. Someone else in this thread mentioned Helmenthic therapy, using parasites in a controlled manner to treat for allergies. If this treatment has seen positive results, perhaps both your point and the proposed theory explain the higher incidence of auto-immune diseases in first world countries.

[1] http://www.arcticstat.org/TableViewer.aspx?S=2&ID=12668 [2] http://www.arcticstat.org/TableViewer.aspx?S=2&ID=12348

Re: Dirt may explain why richest countries suffer diseases rarely seen anywhere else

#37
I'm going to filter this through my skewed outlook on the world and conclude that it's another datapoint in support of travelling the world as much as possible.

We uprooted our 10 month old son last winter and set up shop in a little fishing village in Nicaragua for a few months. He spent his time eating the local dirt while we surfed. And now we have conclusive proof that this was the Best Thing We Could Have Possibly Done for him.

Glad to hear I'm such a great parent.

This article also rings true for me from a personal perspective. I spend a lot of time in the developing world, and make a point of brushing my teeth in the local tap water and eating those poisonous lettuce leaves and local cheese that the Lonely Planet warns you so strongly against. I find that over the years I've gradually stopped getting sick at all while on the road.

I think there's something to be said for training your immune system.

Re: Dirt may explain why richest countries suffer diseases rarely seen anywhere else

#40
post #6

The article reports an interesting observation: "Still, the 500-mile boundary between Finland and this Russian republic marks one of the steepest standard-of-living gradients in the world: Finns are seven times richer than their neighbors across the border. 'The difference is even greater than between Mexico and the U.S.,' Knip tells me." Then the article gets into the main point: "Soon, studies from around the world…

I find the "Old Friends" hypothesis a good answer for why hygiene causes allergies: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1774411/ The basic idea is that the human immune system has co-evolved with a number of immune suppressing parasites. Hygiene has greatly reduced the number of these parasites we're exposed to and without them the human immune system is too reactive. That extra reactivity results in our immu…

The last time I've seen information and discussion about this, I've considered the viability of humans creating an artificial parasite to replace the parasites we are missing right now.
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