Take a deep dive into the importance of gut health,
Research focuses on whether bacteria can affect our nervous system
When it comes to weight loss, how much should you worry about your gut?
The microbiome — the name we give to the two- to- six pounds of bacteria that’s colonized our gut, skin and other organs — has had a pretty meteoric rise to prominence over the past 10 years.
It was barely on the radar until Jamie Lee Curtis started talking up that probiotic yogurt as a cure- all for all digestive issues. Now, a decade later, there are at least a dozen microbiome diet books on the market, most of which promise to reset, balance or restore your gut health so you can feel better and lose weight. Add to this, supplements, probiotic- enriched products, fermented food and drink, and an emerging industry of personalized diet plans based on the analysis of mail- in poop samples. And this is probably only the tip of the iceberg.
Excitement over microbiome research is warranted, since there is a relationship between gut flora and our metabolism. People suffering from obesity, for example, have been shown to have microbiomes that are better at getting every last calorie out of food than those without metabolic disorders.
So, two people can eat the exact same food and have an entirely different caloric intake, which seems pretty unfair, if you ask me. It also explains a lot of interest in “hacking” the microbiome.
“The microbiome has gained a lot of attention in the last decade, but a lot of this is actually based on research from long before that,” says Dr. Premysl Bercik, a gastroenterologist and professor of medicine at McMaster University. “We know that it’s a key factor in shaping and modulating our immune system, it influences the function of the digestive tract and the overall energy metabolism of the body. The next question is about the effect on ‘ distant’ organs, like the brain, for example.”
Bercik’s research focus is, in fact, on the relationship between the gut and brain health, which is promising. One day, he hopes, it might be possible to address anxiety, depression and other disorders with specific strains of bacteria. For now, though, much of the research has only been able to establish relationships between certain types of bacteria and various health issues, since our gut flora is also connected to autoimmune disorders, including fibromyalgia and rheumatoid arthritis. Do the bugs in our gut make us sick, sad and at risk for obesity?
“We know that, when bacterial profiles change, so does the bacterial metabolic activity and this could affect the host, but we have to always be careful because the question is whether this is the cause or the effect,” says Bercik, “Which came first: the chicken or the egg? Did the disease change the microbiome or did the microbiome cause the disease?”
The next phase of research, which is designed to explore specific mechanisms and see if bacteria can actually change the function of the human nervous system, is underway. At this point, though, it’s still largely in the “preclinical” stage — mainly animal research, which may or may not translate to humans.
The upshot of this is that it’s still too early to make really specific claims about certain strains of bacteria and brain health, the immune system and of course, weight loss. Not even with poop analysis.
That said, there’s a growing consensus among nutritionists and researchers that gut health is an important component of overall health and that there are some generally advisable lifestyle and diet changes we can make. These involve stress management, regular exercise, sleeping well and, probably most important of all, cutting back on ultra- processed foods and upping our fibre intake.
Humans need a fairly large amount of fibre ( between 21 and 38 grams per day depending on age and gender). Health Canada says, on average, Canadians get about half as much fibre as they should.
Beyond this, though, you should probably pay a little attention to what kind of fibre you’re eating — soluble or insoluble.
We need both, but “insoluble fibre” — the kind you find in edible plants such as artichokes, brussels sprouts, green beans and peas, lima beans, sweet potatoes and zucchini — can’t be digested and is thought to be a playground for good bacteria. Fibre is thought to help bug colonies thrive inside us.
This is known as a “prebiotic” approach. Instead of spending money buying foreign bugs in a probiotic supplement, try making your own by eating more fibre.
“Taking into account the epidemics of metabolic syndrome all over the world, but especially in North America, people should make proper dietary choices, monitor their caloric intake, and likely avoid processed foods and ultra- processed foods,” Bercik explains.
“There are many studies suggesting that the Mediterraneanstyle diet is probably the best because it’s got an adequate amount of protein balanced with fibre and a high- antioxidant content and is associated with the gut microbiota profiles that, overall, are found in healthy individuals.”
Other than genetics, Bercik says, diet is the most important factor in shaping our microbiome, which will change with our diets — for better or worse.
Upping our fibre through whole grains, legumes and fresh fruits and vegetables is likely more important than loading up on probiotic superfoods and supplements, since fibre is thought to provide a better habitat for bacteria.
Without that, it’s not clear new bacteria has what it needs to set up successful colonies.
“I eat yogurt because I like the way it tastes,” says Bercik, “And apart from the taste benefit, there may be some health benefits. There are studies which showed that specific probiotic bacteria have a beneficial effect, but this has not necessarily been shown with most of the products available in our stores.”
“But from my point of view, the well- balanced diet is probably the best,” he continues. “We should probably be paying more attention to our diet because it could likely address many of the health issues our modern society is facing.”
So, in answer to the original question: Yes, we should be paying attention to our gut. Just not necessarily in the way the probiotic yogurt, supplement marketers and poop- lab companies want us to.