Dirt. It is a sometimes unsightly and unavoidable fact of life for most parents. Indeed, there is no shortage of sweet faces to wipe, small hands to wash, muddy clothes to launder, and sticky floors to scrub. Dirt. Is. Everywhere.

But what if you discovered you’re working too hard to get rid of all that dirt — that keeping some of the dirt around (as well as the germs) is actually healthy for kids?

We are a country obsessed with being clean: clean kids, clean homes, clean pets, clean everything. The cleaner, the better. Store shelves overflow with cleaners promising to kill 99.9% of germs. We want our homes to be germ-free, sparkle, and smell nice, too. We also want the same for our children because in our minds, as parents, dirt equals germs — bad germs, of course — because there’s no other kind, right?

“To think having dirt on you can make you sick is a misunderstanding,” says Dr. Marie-Claire Arrieta, assistant professor of microbiology at the University of Calgary in Canada.

Arrieta attributes this misunderstanding to a lack of research until recently. She explains that until 10 years ago, 99% of research focused solely on bad microbes (aka germs), the ones that make people sick. Only recently have scientists begun to shift their focus and study the different ways microbes can be helpful.

According to Arrieta, microbes are microscopic organisms such as bacteria, viruses, and protozoa.

Together, they form communities within our bodies, known as microbiotas. For example, our gut has its own microbiota. These microbes are with us from birth and interact with us. She explains that only recently have scientists realized just how crucial these tiny organisms are to our bodies, comparing them to an organ.

In fact, scientists like Arrieta are finding that the majority of microbes are not harmful at all and actually offer real health benefits when children are exposed to them within the first five years of life.

Arrieta and renowned microbiologist Dr. B. Brett Finlay of the University of British Columbia recently released a new book, Let Them Eat Dirt: Saving Your Child From an Oversanitized World. Finlay and Arrieta share research from their own labs as well as others, showing how microbes can strongly affect childhood development, with ways parents can use this information to influence their child’s long-term health. It is their position that an imbalance, or lack of, these good microbes can lead to long-term health problems such as obesity, asthma, diabetes, and other chronic conditions like food allergies.

The war waged on germs by parent — hand sanitizers on every school bag, hand-washing at every turn, and antibacterial wipes for every surface and toy — is actually doing more harm than good, Arrieta says. For example, one of her most recent studies connected a lack of key intestinal microbiota to asthma in very young babies.

“We have learned to put all germs under the same umbrella,” she says, yet, “dirt does not equal disease.”

Therefore, parents are constantly wiping away microbes that could be beneficial to their children, all in the name of cleanliness. Toys do not need to be cleaned with bleach, or even at all, unless someone is sick or the toys are visibly dirty, Arrieta says. Even then, they can simply be cleaned with soap and water; bleach is overkill.

Unintended consequences
One casualty of a war waged against dirt by parents is time spent outdoors. Yes, children do spend a good deal of time outdoors on various sports fields, however, there’s something to be said for mud pies, earthworms, and chasing frogs.

“Being outside is not going to make children sick,” Arrieta says. “Childhood is an exploratory phase, and we think part of that is to explore microbes, too.”

In other words, let your children play in the dirt, climb trees, and pick up bugs, as these activities introduce your child to a whole other world of microbes that cannot be found inside the home.

“Kids need microbes for a healthy immune system,” she adds.

Yet a lack of outdoor time, and the dirt that comes with it, is an area in which parents can do better. Arrieta and Finlay note in their book that children spend half as much time outside as they did only 20 years ago.

Outdoor time is crucial because not all microbes are created equal. Arrieta explains that outdoor microbes, whether in our backyard, or at a park, are different from the microbes found inside of our homes. Of these billions of microbes, only a few cause disease. Many are actually beneficial. Furthermore, having children wash their hands every time they come in from playing outside is very unnecessary in most cases.

“We need to balance, as parents, all the ways we know how to prevent disease,” she says. “We should not be wiping people down with the first spec of dirt!”

Instead, Arrieta advises children should wash their hands prior to eating and after using the bathroom. One exception would be if your child has just played in a sandbox. In that case, children should wash their hands afterward due to the high concentration of microbes that tend to reside in a sandbox.

Another consequence of the war waged on microbes has been the abundant overuse of antibiotics in the healthcare industry. Because antibiotics are designed to kill microbes, they do so indiscriminately, killing off both the bad and good germs. They do not differentiate.

“We need them [antibiotics],” she acknowledges, “but we should only use them when necessary because they really wipe out the microbiome.”

She explains the microbiome of an adult will mostly bounce back. However, for young babies the process can be more difficult. A young baby’s microbiome is not as resilient, nor as established. For this reason, Arrieta recommends that if antibiotics need to be used during the first year of life, probiotics should be used as well to help reestablish the microbiome in an infant’s gut. However, she cautions that probiotics are not regulated by the FDA, and any company can claim to sell a probiotic. A clinical guide to probiotic products can be found at letthemeatdirt.com/probiotics.

Tips for parents
1. Here are ways parents can expose their children to the “good” germs that exist all around us, in turn promoting healthy development and building a stronger microbiome, according to Arrieta.
2. Allow children to explore and play outside as much as possible.
3. Allow children to get dirty! Don’t be afraid of the dirt.
4. Consider alternatives to antibacterial soaps, cleansers, and wipes.
5. Allow children to be around healthy pets, such as dogs who bring many good microbes from outside into our homes.
6. Studies have shown dogs may decrease the risk of allergies and asthma.
7. Practice balance when preventing disease. Encourage proper hand washing before eating and after using the bathroom, but not every time a child comes in from outside.
8. As soon as babies can eat solid food, incorporate a variety of fiber. Good microbes thrive on fiber.
9. Swap out refined foods for fruits and vegetables.
10. Use a probiotic when taking antibiotics.