Weren't they kids once? You have to eat a little dirt to be healthy, people.
The Hygiene Hypothesis is not new, but I will recap; basically, your body builds its immune system by tackling small problems, the same way vaccines create small problems to build an immunity against big ones. If you're too clean when you're young, the real world is going to make you sick. Very sick.
In a previous life I ran the business unit of an electromagnetic analysis software company - 'solving' Maxwell's Equations, basically, to help companies find problems before a prototype. My prior experience until then had always been on the design side, dealing with people in groups at Intel and places like that, so I had never been to a semiconductor foundry. Off to Hsinchu, Taiwan I went. I was met by our applications engineer there, who took me on a walking tour and bought me some delicious spiced chicken from a street vendor. And one for the road, he said. Indeed, it was good so a second one for later was perfect.
I returned to my hotel room and the CEO, my boss and something of a semiconductor legend, had an email waiting for me with a wealth of information about the company, TSMC, Hsinchu in general, and then 300 words down, "Whatever you do, don't buy chicken out on the street." Hepatitis is everywhere and they're all immune to it, he noted, but Americans need vaccines.
Well, I didn't know a lot about Hepatitis but it was clearly too late, since I was eating that second chicken when I read his email, but when I returned home a week later I went to a doctor and he did a test and said I didn't get hepatitis nor would I - at least not the kind from eating chicken on the street in Taiwan. I was curious why, since many Americans needed shots, and he asked if I ever lived on a farm. Well, I had and he explained that on a farm, around animals, etc., exposure to hepatitis happened so often (basically, due to poop) an immunity was built up early.
Cleverly-marketed products are creating a culture of 'germophobia', notes microbiologist Dr. Alex Berezow, and that is going to cause more problems than it solves. Triclosan in antibacterial soaps is now being associated with more allergies and as they have become more popular there are concerns about environmental impact. Benefit over soap and water? None.
The Hygiene Hypothesis has an air of truthiness to it but where is the data? So far it is correlation but it's compelling correlation. Autoimmune diseases are way up in rich countries but not in poor ones where they don't have helicopter parents overpaying for antibacterial soaps. Berezow also discusses 'helminth therapy', which involves deliberate infestation with parasitic worms. This stimulates low levels of pathogenicity that may have been missing due to lack of exposure to organisms humans had throughout history - until now - and has had success in clinical trials.
It doesn't mean you should stop taking showers, just let kids get messy once in a while.
Article: CNN - We're a nation of germophobes