Let’s face it: the 20th Century was an unqualified success for modern medicine in eradicating debilitating and fatal diseases. No one can argue that ending the threat of terrifying conditions like polio and smallpox was a huge victory. Unfortunately, since every rose has its thorn, in our overzealous attempt to destroy every possible germ, virus, and speck of bacteria, we have now sterilized, pasteurized, and irradiated ourselves into a hyper-clean environment in which we have to go out of our way to introduce beneficial bacteria into our bodies.

But this isn’t just true for adults. Babies seem to know something we don’t. There’s a reason they put everything they touch right into their mouths: maybe the innate wisdom of their bodies is telling them they need exposure to some germs. Barring choking hazards, of course, this isn’t the worst habit they could get into for their health.

In our modern era, children might benefit even more than adults from probiotic supplementation. More time spent indoors on video game systems, phones, iPods, and tablets means less exposure to the natural world’s pollen, dander, and microscopic soil particles. Children’s immune systems aren’t getting as familiar with these things as they might have in the past, and therefore aren’t learning or “being programmed” to build up appropriate physiological responses. Immune systems that are underdeveloped or have been under-challenged might overreact upon exposure to certain substances. This can lead to environmental allergies, food intolerances, asthma, eczema, and other conditions that affect overwhelming numbers of children.

Many of these conditions are extremely common nowadays, but being “common” doesn’t mean they’re normal. It more likely means that most children’s immune and digestive systems are somewhat underdeveloped—partly due to far more time inside clean environments than in years past, and partly due to events before and during birth, and a lack of live, cultured foods as they grow into adolescents.

Studies have shown that the gut flora of a mother can influence that of her developing baby. It used to be believed that the GI tract of a fetus was sterile, and that it got its first dose of good bacteria by swallowing some of the microbes in its mother’s body as it passed through the birth canal during delivery. It is now known that amniotic fluid and umbilical cord blood contain beneficial microbes, and the mother’s prenatal diet affects the makeup of those microbes. Babies born vaginally and then breastfed tend to have the strongest immune systems and GI health. Babies born via C-section miss out on that all-important first dose of good bacteria, but they will still get some exposure in utero. Formula-fed babies are at a disadvantage compared to breastfed babies, because breast milk contains a wealth of diverse immune factors and microbes that even the most advanced medical technology can’t replicate perfectly. But that doesn’t mean these babies will automatically experience allergies or illnesses. There are safe and effective probiotic supplements now available for infants, which is reassuring, since there will always be cases of medically necessary C-sections, and women who, despite their best efforts, are unsuccessful with breastfeeding.

Aside from making sure both mom and dad have healthy diets and good, diverse gut flora prior to conception, a good and easy way to give growing kids a bacterial boost is to let them do what kids do best: play in the dirt!


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