Trillions of bacteria line our digestive tracts, and they're extremely important. They support digestion by breaking down tough plant fibers, and they synthesize vitamins your body can absorb.
But the only way to keep them happy is to keep them fed. And if you aren't eating the right foods, mouse studies such as this one suggest, these bacteria may turn to the next available snack: the lining of your gut.
So how can you keep their intestinal munching at bay? Eating a fiber-rich diet every day may help, according to new findings in mice.
A breakdown of the stomach lining is not good. It can lead to inflammation, irritation, and inflammatory bowel diseases like ulcerative colitis and Crohn's disease.
The multifarious collection of bacteria in our guts generally munch on dietary fiber — the roughage we get from plants, whole grains, nuts, seeds, fruits, and vegetables. Fiber helps with digestion and makes you feel full.
But fiber may play a more important role than we knew. According to a study in humans out of the University of Illinois, the amount of fiber in our diets might impact the structure and function of bacterial colonies in our guts. And when intestinal bugs are starved of fiber, as reported by Scientific American, they either die off or start feeding on the lining of the gut.
A more recent study of mice and their gut bacteria further supports this idea. Eric Martens, a microbiologist at the University of Michigan Medical School, presented this work at the Keystone Symposia conference in March, 2015.
After feeding rodents a diet devoid of fiber, Martens discovered that the protective mucous lining of their intestinal tracts thinned dramatically. Meanwhile, another group of mice fed a fiber-rich diet had healthy gut linings.
But the most interesting finding came from a third group of mice. Martens alternated between giving this group a meal high in fiber one day, and a meal with no fiber the other, "like what we would do if we were being bad and eating McDonald's one day and eating our whole grains the next," Martens told Scientific American.
Lo and behold, part-time fiber binges weren't enough to protect their guts. In fact, the mucous lining of their intestines measured to only about half the thickness of the intestinal linings of mice on high-fiber diets.
If these findings translate to humans, Martens said in the article, it would mean that we would need to eat a high-fiber diet every single day in order to keep our guts healthy. Just how much fiber, however, is still unknown.
Beyond bacteria helping us break down tough plant fibers and synthesizing essential vitamins, a slew of studies are suggesting that they may play even broader roles.
A healthy mix of microbes could help ward off obesity and diabetes, and studies indicate that they may have some role in depression, autism, inflammation, and even cancer.
Eating more fiber may be the key to keeping your community of intestinal bugs happy and healthy, but it's hard to say for certain unless you're a mouse. (Researchers will have to study this idea in humans to know for sure.) Because it's unlikely that having a lot of fiber in your diet is a bad thing, though, it wouldn't hurt to see if you're eating enough roughage. The USDA recommends 25 grams per day for women and 38 grams per day for men, but most Americans are not hitting those targets.
So now is as good a time as any to stock up on some beans, nuts, and berries — if only for the good of the helpful critters in your gut.
