Metchnikoff had observed that people in rural populations with diets heavy in bacteria-rich fermented milk products were unusually healthy and long lived. So confident was Metchnikoff in this theory that, for the rest of his life, fermented milk made up a large part of his diet.

In the century since, the science of probiotics has progressed dramatically, though the most promising research has largely happened in the last two decades. “Science moves along at pace with technology,” explains Dr. Richard Fedorak, President of the Canadian Digestive Health Foundation (CDHF). “So, while we recognized a hundred years ago that gut bacteria were important, we had no way of measuring them.”

The microbiome

Now that the technology to better examine human gut flora exists, the findings are astounding. The average person has trillions of beneficial microbes, from hundreds or even thousands of different species, living in their digestive tract. In fact, you have more than ten times as many microbial cells in your gut than you have human cells in your entire body.

And these microbes provide vital autoimmune function, being implicated in the prevention and management of conditions as varied as asthma, allergies, certain cancers, IBS, and IBD. “We’ve only recently begun to recognize that our gut microbiome is an organ, no different from the heart or liver,” says Dr. Fedorak. “It plays an essential role in overall health.”

“We’ve only recently begun to recognize that our gut microbiome is an organ, no different from the heart or liver.”

The CDHF refers to these gut microbes as protective superheroes and, in healthy adults, these superheroes have the diversity and balance required to keep us safe against harmful pathogens. “The gut is representative of 70 to 80 percent of our immune system,” explains alternative medicine expert Bryce Wylde.

But in times of stress or illness, particularly when travelling, it is easy for this microbiome to become unbalanced, which can result in diarrhea, lowered autoimmune function, and negative impacts throughout the entire body. Restoring the superheroes in these cases can be as easy as taking a supplement or introducing probiotic foods like yogurt into the diet, but choosing the right product is essential.

Not all yogurts are created equal

“In 2003, if you asked someone on the street, or even a dean of medicine at any major university, what a probiotic was, they would have looked at you like you had two heads,” says Dr. Gregor Reid of the Canadian Centre for Human Microbiome and Probiotic Research.  “Then, in 2004, Danone launched Activia in Canada and put the word ‘probiotic’ into the vocabulary of Canadian households. Shortly thereafter all the other major brands followed with competing probiotic yogurts of their own.”

It may seem strange that yogurt has been providing probiotic health benefits for thousands of years and yet none of the yogurt products at the grocery store in 2003 contained any probiotics at all. The reason is that commercial yogurt was being heat treated to prolong shelf life and, before the probiotic revolution of the early 2000s, the fact that this also killed off all the active cultures was seen as a plus. And so, modern probiotic yogurts have carefully reintroduce the beneficial microbes that ancient populations had been enjoying for millennia.

Showing that sometimes you have to take a step backwards to go forwards.

It’s incredible that something as simple as eating functional foods like probiotic yogurt can have such a profound effect on wellness but, a hundred years after Metchnikoff, the science is finally catching up and showing that indeed, a healthy gut is the key to healthy body and a happy life.