by Dr. Bill Rawls
What causes irritable bowel syndrome (IBS)? Dr. Bill Rawls explains how the foods we eat, along with factors like stress, disrupt our gut microbiome and lead to chronic illness. Plus, he reveals the best IBS diet for improving symptoms and ending the cycle of chronic GI misery. Get a complete guide to overcoming IBS here.
Question: What Causes Irritable Bowel Syndrome?
Hello, this is Dr. Bill Rawls. Today I want to talk to you about irritable bowel
syndrome, or IBS. This is something that affects a lot of people — possibly even half the population.
Briefly, irritable bowel syndrome is an effect of what we eat and our surrounding environment. So many of us are eating a diet that really is nothing like what humans have been exposed to through time.
Historically, humans have eaten a lot of vegetables and meats, and now we’re eating this heavily grain-based diet. The starches, the fiber, in those foods, and other things like lectins and gluten that we find in wheat, all have an adverse affect on our intestinal tract. But the starches, especially, are affecting bacteria in our digestive system.
We all have a huge collection of different microbes in our intestinal tract, and they respond to whatever we feed them. The purpose of our digestive tract is really extracting nutrients to feed our cells, but everything else that’s there feeds bacteria.
So if you’re eating vegetable and fruit fiber, that feeds a certain type of bacteria—or a spectrum of bacteria—that are normal for us. If you’re eating a lot of grains or a lot of grains and beans, that’s growing a whole new garden of bacteria in the gut.
If you’re growing a garden of bacteria that aren’t favorable to you, that can cause a lot of problems. And it’s often compounded by stress, because stress slows down the entire intestinal tract. If you’re growing these bad bacteria, they’re fermenting all of these starches, and that’s producing gas, it’s producing toxins, it’s activating the immune system.
Now, bad bacteria have the effect of producing, via fermentation, chemicals called amines. Bad bacteria also tend to produce signaling agents, and those things cross over and affect our brain. They can affect our mood. They can affect everything about the way that we feel.
So it’s not just the gut. But in the gut specifically, when you grow these bad bacteria, the toxins can slow down the intestinal tract and make it very sluggish. That can cause chronic constipation, but it can go the other way, too. Sometimes these toxins actually damage the cells that line the intestinal tract, especially the large colon, so you have leaking of fluid into the large colon and you get this flushing effect.
And a lot of times it goes back and forth. You’ll start with constipation, and that will build up all these toxins, and build up and build up until you get this flushing effect, and that goes on for a while until things start healing. And then it shifts back to constipation. But it ends up being a chronic misery that can go on for a lifetime.
The solution, of course, is changing what you’re eating, shifting to a vegetable-based diet. More than half your food should come from vegetables, shifting away from such a heavily grain-based diet. And beans also can contribute to these problems. It doesn’t mean that you can’t have any of those things — though sometimes with recovery, you need to cut them down or cut them out for a while. But it means that the majority of your food should come from vegetables.
Meats can go either way. Eating a lot of meat can grow a different spectrum of microbes that can cause a lot of gas and sometimes a lot of odor along with it. So if you want a healthy diet, vegetables are really important. Fruit can be part of that, but not an overload of fruit.