In the following article they talk about how as our connection to the earth and exposure to microorganisms have decreased the rates of depression have increased. I find this idea very interesting. I had posted another article about how microorganisms in dirt were proven to release serotonin. Maybe God knew what he was doing when he set up our natural relationship to food and its cultivation.
Let your kids get DIRTY!!! Stop with the baby wipes and antimicrobial soap. You could making yourself and your kids depressed. Check out the link below for the full article.
Look for my other post under depression for the article I mentioned from about a year ago.