It seems those with allergies are always trying new ways to protect themselves and their kids from sneezes, runny noses and itchy eyes every allergy season. New information suggests that the best way to protect against allergies is to go out and get dirty—while you’re still a child, that is.

Microbiologist Jason Tetro said in an interview with CBC that a Finnish study found that healthy children without allergies had more good bacteria, or symbionts. Kids with allergies had more bad bacteria, or pathobionts.

Tetro explained that the immune system decides how the body will react to bacteria. The immune system will assess pathogens based on tolerance, combat and sensitivity. The system will try to get rid of pathogens by creating more mucus, preventing them from further entering the body by causing a reaction.

When there is an excess of bad bacteria, the body won’t tolerate it, so the body will use sensitivity to try to get rid of the pathogens without going into combat mode. This situation causes contact with allergens, and since there is an excess of bad bacteria, an allergic reaction occurs.

The best way to protect the body against bad bacteria buildup, and therefore allergies, is to allow the body to build up as much good bacteria as possible. Tetro explained to CBC how crucial the first year of life is in developing this healthy bacterium, “It’s really fascinating that the first year of life is the most important when it comes to allergies. It seems like breast feeding, getting kids out to play in the dirt and getting exposed to friendly bacteria is the answer.”

Once the body is exposed to different bacteria, our immune systems build up, therefore making it harder for bad bacteria to grow, preventing allergies.

So what’s the best way to stop your kid’s runny noses and itchy eyes? Tetro says, “Let them eat dirt, is what I always say.”