Getting to the bottom of why allergies are on the rise involves consideration of several theories. One major theory is the hygiene hypothesis, which basically posits that our bodies are becoming more susceptible to harmless "invaders" – including allergens like dust mite allergen, pollen, and pet dander – because our immune systems no longer have to work to attack stronger germs.

Think, for instance, of the farmer's child who spends hours among animals and even around dirt – much more than an urban child whose mother chases him with hand sanitizer all the time and stocks the house with antibacterial products.

A recent Parenting magazine article featured on CNN.com, Why you should love germs, discusses this very issue. It's better, in many cases, to let germs help boost your child's immune system:

"…overall, when it comes to germs, most people have it backward: With relatively few exceptions, they are good for our kids.

"Keeping things clean is smart, but going crazy using antibacterial hand soaps, buying antibacterial kids' toys and other products and overusing antibiotic medications is actually killing off the microbes that can help strengthen the immune system."

In fact, the article goes on to suggest that parents give their children foods that actually help promote the good bacteria, which helps regulate our immune systems and keeps us healthy. Such foods include yogurt, pickles, dark chocolate, and feta cheese.

In addition, parents should not insist on antibiotics when the doctor says they aren't necessary; antibiotics kill beneficial bacteria as well as infection-causing bacteria. If antibiotics are needed, children over six months old can be given probiotics to help restore a healthy balance of good bacteria to their immune systems.

For more information, see:
BPA, Triclosan Linked to Allergies
Antibacterial Soaps: Being Too Clean Can Make People Sick, Study Suggests
Hygiene Hypothesis
Probiotics and Allergies