Kids benefit from being kids and rolling around in the grass.

In which cities are people favouring local parks over toilets?

Parasites can actually help with allergies. I am loosely aware of various attempts at treating allergies using parasites.

One of the approaches taken (under medical supervision) for kids with bad nut allergies is to gradually expose them to more of the allergen. Being able to survive a peanut or two without anaphylaxis is life-changing.