The eyes may be the “window to the soul,” but the gut is the window to our health. Our stools contain a wealth of information—about our nutrient balance, our metabolism and even warning signs of disease.
Gut fanatics on social media have jumped in on the promise of poo. Known as “poop maxxing,” or more politely, “fiber maxxing,” there is a swell of enthusiasm for high-fiber foods, regular bowel movements and the quest for a healthy gut.
Put bluntly, unless you have specific symptoms (more on these in a moment), there is no reason to obsess over your excrement. But there is some truth to these trends, microbiome experts say.
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“I think that poop maxxing and fiber maxxing are some of the more legitimate health trends that I’ve heard about,” says Bill Sullivan, a microbiologist at Indiana University.
The reason why has to do with the power of fiber, he says. A person’s recommended daily fiber intake depends on age and sex, but the U.S. Department of Agriculture has historically recommended ranges from 22 to 34 grams for adults.
“There is sound evidence that if you increase the amount of fiber up to the recommended levels—you don’t need to go beyond that—you are going to gain a lot of physical and mental health benefits, no question,” Sullivan says.
Here’s everything you need to know to help maximize your gut health.
What does poop have to do with my health?
The gut is “the biggest endocrine organ you have in your body,” says Justin O’Sullivan, a professor of genomics at the University of Auckland in New Zealand. The gut also contains at least 100 million neurons—earning it the nickname “second brain” for its likely role in influencing our mood. “Sometimes we just don’t realize how core to us it is in many ways,” O’Sullivan says.
Our gut is “loaded” with trillions of bacteria, fungi and viruses that together support and influence our physical—and mental—well-being, Sullivan says. Bacteria produce vitamins and short-chain fatty acids that serve as “a potent anti-inflammatory,” as well as the hormone serotonin, which helps regulate appetite, he adds.
Bacteria are also responsible for the mucus barrier along your gastrointestinal tract that prevents toxins from leeching into the bloodstream, Sullivan says.
Research even suggests gut health may shape aging, Sullivan says. Long-lived healthy adults tend to have microbiomes that are richer in bacterial diversity than those of their chronological peers, with the former having gut bacteria that look more like those of younger, healthier adults. The reason why is a mystery—scientists are still working to untangle whether a healthy gut drives longevity or is a by-product of it.
One way to find out how the gut shapes health is to conduct clinical trials involving fecal transplants. In one study involving teens with obesity, for instance, O’Sullivan and his colleagues found that participants who ingested fecal transplant capsules loaded with healthy gut bacteria had better metabolic health years later than those who didn’t. O’Sullivan is also researching how the microbiome may support gut function in people with autism and aid in the treatment of anorexia nervosa.
How can I tell if my gut is healthy?
It’s not totally clear how your microbiome influences your overall health, Sullivan says. A combination of genetics and environment shape this relationship. But, he adds, “if you’re eating a healthy diet of real foods that are rich in fiber, if you’re getting sufficient exercise [and] a good night’s sleep and engaging in stress reduction to the best of your ability, you’re doing the very things that are going to cultivate a healthy microbiome.”
The Bristol stool chart—a tool doctors use to get assess your poop’s consistency—can also offer a guide to indicate “whether you’re on track with things,” Sullivan says, but there’s no reason to fixate on your feces during each trip to the bathroom.
In general, poop that comes out consistently “really hard and cracked” or like “little, tiny balls,” is unknot ideal, O’Sullivan says, because it may indicate constipation. The same is true on the opposite end of the spectrum—you don’t want stools that are like liquid. Somewhere in the middle, with a consistency he describes as “like peanut butter,” is best.
It’s also worth noting that some variation in your stools’ color and texture is normal, but if you see blood in the toilet, “that is definitely worthy of seeking medical attention,” Sullivan says. Red blood may be a sign of hemorrhoids, diverticulosis (small pouches in the colon), and more, while black or tarry feces can be a sign of internal bleeding in the colon, small intestine or stomach—and is linked to cancer, ulcers and inflammation.
What foods should I eat to get more fiber?
Whether or not you are fiber maxxing consciously, if you’re interested in boosting your gut heath, your best bet is to “eat the rainbow,” Sullivan says. “Eat a wide variety of different foods, as many as your taste buds will allow.”
“The diversity feeds your microbiome,” O’Sullivan adds. Building gut diversity takes time, but “having fiber, having plant material, having nuts, seeds, protein—all of those things feed your biome.”
Both soluble and insoluble fiber are important for gut health. Soluble fiber helps form that essential, slimy gut barrier and “mops up” cholesterol from the body, Sullivan says. Insoluble fiber keeps you regular, helps prevent hemorrhoids and feeds anti-inflammatory bacteria species in the gut.
But both experts have a warning: be careful not to overload your body with too much fiber, because that can cause cramping and diarrhea. “I would recommend a slow and steady change,” Sullivan says.
