"Of course the comment was "tongue -in-cheek."
"But we have become such a risk adverse society.
"I see hand sanitizer available to the public for free in so many places these days -- supermarkets, department stores, etc. This has got to be a bad idea. Soon we won't have an immune system."
Americans have never been known for moderation. If a limited amount of something is good, then more must be better. :( That said, I do believe there are public situations where using hand sanitizer makes sense, physicians offices and hospitals for instance, particularly during flu season, as they are concentrators of sick people by definition. I believe the same applies to the back country. but CYOH is the operative phrase here, just like HYOH.
+1 to supermarkets, department stores, etc.
That said, I doubt very much that using hand sanitizer has any more of a lasting impact on one's immune system than washing the hands. Both effectively remove pathogens from the affected area, which will soon be repopulated from adjacent skin areas in the course of the hundreds of touching motions that occur every day, scratching, rubbing, etc.
"When I was a kid we were always dirty from playing outside. My mother made us wash our hands before meals and we took a bath once a week. We never got sick."
I grew up under the same conditions, and heartily concur. Numerous conversations I have had with docs I know socially reinforce my opinion on this one. The real problems with our immune systems start early on, beginning with the increasing frequency of cesarean births, which deprive the newborn of its first exposure to immune system stimulants.
"A good friend of mine grew up in rural India. He told me the local water sources usually had greenish water. He never got sick."
This one is a bit more complicated than that. My wife was born in what is now Bangladesh and spent the first 12 years of her life in what is now West Bengal, under similar conditions. She survived, as did your friend, but millions of other Indian kids didn't and don't. It is a harsh environment and many do not make the cut. Those who do have very strong immune systems indeed, a phenomenon I have discussed with medical professionals on site in Iraq, Iran, and Afghanistan. An interesting related aspect of this involves Indians who emigrate to the West and spend years here, then go back to India and get sick just like a lot of Western tourists do, because their immune systems are no longer primed to resist the local pathogens. It a battle that requires constant stimulation to keep up resistance, a lot like having to get booster shots for typhoid, tetanus, etc. I always "self inoculate" when visiting India by eating lots of yogurt. It is not a cure all, but it jump starts the process of adjusting to the local flora by stimulating my immune system and introducing some local allies into my gut.
"I am sure some health expert here will point out the dangers and provide case studies to disprove all of this. I think we are all a bunch of sissys ;)"
+1 to both statements. :)