Consider this: The average person’s body contains about 100 trillion cells, but only maybe one in 10 is human.
This isn’t the latest Hollywood horror flick, or some secret genetic engineering experiment run amok.
This, it turns out, is nature’s way: The human cells that form our skin, eyes, ears, brain and every other part of our bodies are far outnumbered by those from microbes — primarily bacteria but also viruses, fungi and a panoply of other microorganisms.
That thought might make a lot of people lunge for the hand sanitizer, but that impulse may be exactly the wrong one. Researchers are amassing a growing body of evidence indicating that microbial ecosystemsplay crucial roles in keeping us healthy.
Moreover, scientists are becoming more convinced that modern trends — diet, antibiotics, obsession with cleanliness, Caesarean deliveries — are disrupting this delicate balance, contributing to some of the most perplexing ailments, including asthma, allergies, obesity, diabetes, autoimmune diseases, cancer and perhaps even autism.