I’m a UC patient who’s devoted to the microbiome.
Many ulcerative colitis and Crohn’s patients find that the gut microbiome, aka the gut’s population of bacteria, is key to getting into remission. I’m among them.
After achieving my first UC remission through drinking kefir, I came to consider both sauerkraut and kefir, with their live probiotic cultures, to be medicines as potent for me as any drug. I found that if I went without either for more than a couple of days, my colitis symptoms worsened.
In the last post, I told the story of that first remission. In this one, I want to go over some of the science and thinking about the microbiome and inflammatory bowel disease (IBD).
This post is one part fact and one part speculation on my and others’ parts. But I’m not a medical professional or a microbiologist—my background is in conservation science. Although I try to be precise in my writing, I’m writing here as a fairly well-educated patient, not at all as an expert. So the speculation here isn’t backed up by science; please forgive any misstatements. And please let me know if anything should be corrected!
I find the field of microbiome science fascinating; it’s a cutting-edge world with new research published every year. I can’t help but think that if the real microbial scientists can understand the microbiome, they might just get a handle on what causes IBD—and how to heal it. So go, scientists, go!
IBD patients have messed-up microbiomes—but why?
Humans have trillions of bacteria in our guts, typically hundreds or even a thousand species. These bacteria (and also yeast and fungi) are crucial to our health. Here is an excellent article summarizing the microbiome’s many roles, with links to scientific papers if you’re interested.
A dysregulated microbiome is common, perhaps even universal, among IBD patients. Our microbiomes are out of whack. We typically have far less diverse, and far less stable, populations of bacteria than do healthy people.
It’s not yet known whether this dysregulation is a cause of IBD or a result of IBD. It’s hard for scientists to determine whether it happens before or after disease onset, and numerous studies have tried to answer this chicken-or-egg question. One small 2018 study does seem to point to microbial dysregulation coming first and possibly acting as the trigger for IBD, but the jury is still out.
It’s important to note this: correlation is not causation. Although it makes intuitive sense that an unhealthy microbiome might trigger an overblown immune response in the colon, the opposite also makes sense. IBD could first manifest in the colon for some other reason, perhaps related to genetics, just as autoimmunity mysteriously manifests in various other parts of the body. Once the colon becomes inflamed, it might then be rendered unable to support a healthy microbiome—hence the dysregulation.
It’s possible (but not at all certain) that messed-up microbiomes cause IBD.
However—and again, this is not scientifically verified—it does make a lot of sense that IBD could be caused by disruptions in the microbiome. Such disruptions might occur, in part, due to diet and lifestyle.
That would explain IBD’s rapid rise in the world as diets and lifestyles change with modernity. In particular, it would explain this disease’s rise in populations that are adopting the modern Western diet.
Diet can dramatically affect the microbiome. Various studies link diet to the microbiome as well as to IBD. This study, this study, and this review of studies all found that a diet high in fiber and low in animal products seems to help prevent UC or IBD. Studies like these seem to indicate that the modern Western diet, with its high amounts of processed food, carbohydrates, sugars, and animal products and its low amounts of fruits and vegetables, depletes the microbiome and may trigger IBD. And this excellent, in-depth article points out that certain specific bacterial groups, such as Lactobacillus species, seem to protect against IBD.
Like the small 2018 study mentioned above, all this science helps bolster the idea that diet and lifestyle might lead to IBD through alterations in the microbiome. This isn’t the whole story—various other factors, many of which are outside patients’ control, make us susceptible to autoimmune diseases like IBD. I’ll talk about those other factors in a future post. (Update: Here is that post!)
I suspect diet and lifestyle hurts the microbiome, which leads to IBD.
My working hypothesis (which is shared by some scientists) is that many people living in modern society do damage to our microbiomes through diet and lifestyle, and that some of us, who are more susceptible because of genetics, environmental toxins, and other factors, fall ill with IBD because of this damage. In other words, I tentatively suspect that the messed-up microbiome comes first and IBD second.
This hypothesis would help explain why I got IBD when I did. I probably had a typical (not great) American microbiome—I’d had several courses of antibiotics as a child to treat ear infections, and my diet had always had a lot of pasta and cheese and not a whole lot of probiotic foods, veggies, or insoluble fiber.
Then, in the year leading up to colitis, I’d eaten particularly unhealthy in an effort to gain weight before pregnancy. I’d always been a little underweight due to a naturally high metabolism, and when I told a nurse I hoped to get pregnant, she advised me to put on weight. I wasn’t trying to be unhealthy, but my (then) iron gut had always allowed me to eat anything, so to gain weight I just packed on more carbs, meat, and dairy. I was also more sedentary than ever before that year, because I began writing at home instead of biking to work at my former science job. Exercise, like fiber, has been shown to boost healthy gut bacteria.
After ten months of this unhealthy diet and lifestyle, my symptoms began.
Once I came to realize I might have caused my colitis, at first it added to my despair over having this terrible illness. I would spiral into regret at times: if only I’d known what risks I was taking in changing my diet; if only I could go back in time!
But gradually, I realized that 1) it isn’t certain that my diet did cause it, 2) many others with healthier diets also get colitis, and 3) most importantly, I couldn’t have known the risks and wasn’t to blame. All of these thoughts helped. Over time, I reached a state of acceptance, so that by now, writing years later, I approach this question with genuine curiosity and no anxiety.
In the next post, I’ll share my strategies for strengthening the microbiome, whether or not you have IBD.
