With International Women's Day on the horizon, I'd like to shed some light on one fascinating female accomplishment that has yet to be given its due respect – and, frankly, is impossible to see without a microscope.
Back in 2012, the entirety of the 100 trillion germs that live inside and on our bodies was finally unveiled and called the human microbiome.
Though this was a long-awaited milestone, it was only the beginning in opening the door to new branches of science based on the nature of our relationship with germs.
One such field, based on joining the microbiological with the anthropological, is aimed at understanding the origin of the microbiome and its dynamics over the millennia.
Although still in its infancy, the research has already produced one critical piece of information. When it comes to microbial health, we need to rely on a woman's microbiome in particular.
Throughout human history, women have been tasked with several major roles, one of which is child rearing. From birth to young adulthood, a child would be closely associated with females and their microbiomes as a result of child birth, breastfeeding, continued touching and shared travel. In the process, the developing immune system would learn to accommodate and even enjoy the presence of these female-derived microbes that came into the body through the birth canal, breast milk, touching and kissing.
Over time, the child's microbiome would most closely resemble that of either the mother or the group of women in the surrounding area. Depending on the environment in which the child was reared, the microbiome would be different, a fact that holds true today.
But what makes this story even more fascinating is that in order to stay healthy, as we've learned through research, the microbiome needs to be stabilized as any significant shift can lead to disease.
Humans have a core microbiome made up of a few hundred to thousands of types of germs. If they are present, there is a good sense of health. But if they go away, either through dietary or lifestyle changes, then problems can begin to occur leading to acute and chronic conditions including obesity, diabetes, psychological disorders and cardiovascular disease.
As to the origins of that core, to no surprise to any microbiologist, the bacteria come from the mother and the women who rear children. Thus, for every human to remain healthy, the microbiome needs to match or at least resemble that of the child-rearing women. This means that the diet, the environment and even contact with others should be similar in nature.
Hence their role in the mating process. While ancient cultures never used kissing as a means to find a mate – it was simply an act of food sharing – modern society views this touching of lips and sharing of saliva as a part of the ritual of selecting a spouse. When the microbes of the mouth meet the immune system of a potential partner, a reaction happens. If the microbes are seen as friendly – similar to the rearing women – then there will be a sense of harmony and happiness.
If, however, the germs are foreign to the system, inflammation will incur as well a sense of unease, ruining any chance for a long-term relationship. As a result, those with the most closely resembled microbiomes will find themselves making the best mates.
Further research into the links between the female microbiome and society will no doubt unveil even more fruitful facts. For now, as we prepare to honour women the world over on March 8, we can all take a moment to be thankful for women for their beneficial microbes, for making the human species happy and healthy.
Jason Tetro is a Toronto-based microbiologist with over 25 years experience in research. He is a self-described germs relationship therapist and strives to improve humanity's bond with the unseen world. He writes for national and international media outlets and is often found on social media where he shares his unique views on microbial health. His science bestseller, The Germ Code (Random House/Doubleday Canada) is now available on shelves all across the nation. You can follow him on Twitter at @JATetro