Evidence supporting the hygiene hypothesis has been mounting for nearly a decade.  I was pleasently surprised to see this story in the USA Today suggesting that conventional medicine is finally adopting this approach.

This is important as asthma alone accounts for half a million trips to the hospital a year in the United States, including 2 million admissions to the emergency room.

Preventable allergies are costing this nation's health system a frightening $18 billion annually. Much of this spending can be blamed on asthma, especially useless drugs that can be fatal to your health.

Please understand, the world you live in today is not the place your body was meant to live in. You were meant to have regular contact with dirt and everything it comes with. When you do so, especially growing up as a child, it trains your immune system to function correctly.

Simply speaking, your immune system is composed of two main groups that work together to protect you. One arm of the immune system deploys specialized white blood cells, called Th1 lymphocytes, that direct an assault on infected cells throughout your body.

Counterbalancing this, another arm of the immune system attacks intruders even earlier. It produces antibodies that try to block dangerous microbes from invading the body's cells in the first place.

This latter strategy uses a different variety of white blood cells, called Th2 lymphocytes. The Th2 system also happens to drive allergic responses to foreign organisms.

At birth, an infant's immune system appears to rely primarily on the Th2 system. But the hygiene hypothesis suggests that the Th1 system can grow stronger only if it gets exercise, either through fighting infections or through encounters with certain harmless microbes. Without such stimulation, the Th2 system flourishes and the immune system tends to react with allergic responses more easily.

This process is also a good reason for you to limit your use of antibacterial products and antibiotics, and research the pros and cons of vaccines before you make the decision to use them on your child.