Bowel Habits Are a Daily Signal of Gut and Nervous-System Health

Trisha Pasricha’s central correction is that bowel health should not be judged by whether a person goes once a day. Stool frequency, form, effort, and timing are signals from a system shaped by circadian rhythm, microbes, pelvic-floor mechanics, hormones, stress, travel, medications, and the nervous system. The useful question is not whether a person matches a single benchmark. It is whether they know their own baseline well enough to recognize meaningful change.

The once-a-day idea feels persuasive because the colon really is primed to work in the morning. Unlike the heart and lungs, which keep functioning through sleep, the colon enters what Pasricha called a “quiescent state” overnight. After waking, there is usually a one- to two-hour window when the colon begins contracting more actively. That window often coincides with other bowel-stimulating cues: coffee, which stimulates a bowel movement in at least one in three people; walking the dog; morning activity generally. Morning is an efficient time for many people to go. It is not the definition of normal.

Pasricha cited a national survey analyzed by colleagues at Beth Israel showing that bowel frequency from once every three days to three times a day can fall within the normal range. People increasing fiber may start going two or three times a day, and that can be healthy rather than alarming.

The better clinical questions are whether the bowel movement is effortless and whether the pattern allows someone to live normally. A person who goes once a day but strains for 20 minutes is more concerning to Pasricha than someone who goes more often without difficulty. Likewise, three bowel movements a day may be unremarkable for one person and socially disabling for another if it makes work, lunch with friends, or travel feel impossible.

John Torres framed the practical threshold as interference with daily living: when bowel habits start disrupting activities, socializing, or routine functioning, “red flags start going up a little bit.” Pasricha agreed, emphasizing that bowel patterns are not fixed. Food, fiber, exercise, travel, sleep disruption, circadian disruption, and stress can all change what happens in the bathroom. Stress, in particular, plays an underappreciated role.

That variability is why Pasricha urged people to look at their stool regularly. Not obsessively, but consistently enough to know what is usual. In medical training, she was struck by patients who said they did not look. Her response was blunt: if you do not know your pattern, it is harder to recognize meaningful change.

Blood in stool is an obvious warning sign, and she hoped people would act on it by talking to a doctor. But she emphasized that in early-onset colorectal cancer, sometimes the only sign is a change in bowel habits: looser stool without a clear dietary reason, newly hard stool, or a change in caliber, such as stool becoming very thin. Early-onset colorectal cancer is not common, she stressed, but early detection is important. The habit of looking is what allows someone to say, “This is weird for me,” and raise it with a physician.

The Bristol stool scale gives patients and clinicians a shared language for one important dimension: form. Developed in Bristol, England, in the 1960s and 1970s, the scale runs from small hard “rabbit pellets” to liquid stool. Form correlates with transit time through the colon. One job of the colon is to absorb water from its contents back into the bloodstream. The longer stool remains in the colon, the more water is removed; harder stool often reflects longer transit, while looser stool reflects shorter transit. Many people aim for the middle of the scale — Torres noted that in Pasricha’s book, type 4 is where the “angelic chorus” kicks in — but Pasricha returned to comfort, effort, and function rather than a single ideal.

Trisha Pasricha wrote a book using the word “poop” because, in her view, euphemism gets in the way of useful care. She grew up as the daughter of a gastroenterologist and did not inherit the same stigma around bowel conversations that many patients bring into clinic. In medical school and practice, she realized how hard it can be for people to name what is happening in their own bodies. Some students in her clinic had never heard the phrases “bowel movement” or “bowel habits” used directly and were unsure whether the doctor was asking about poop at all.

Her clinical experience is that plain language changes the room. When she asks patients to tell her about their poop, many relax and describe problems they have never told anyone. She also acknowledged that she has misread the room; some patients prefer more formal language, and she adapts to the person in front of her. But overall, she finds the word itself often reduces tension.

Younger people, especially Gen Z, seem to her more willing to discuss bodies and mental health without the same shame. Pasricha sees that as beneficial, especially given the gut-brain connection she studies. The body systems involved are too important, in her account, to be left to euphemism, embarrassment, or childhood memories of being scolded for farting at dinner.

The practical risk is that ordinary embarrassment can keep useful details out of the clinical conversation. Patients may hesitate to report incontinence, bleeding, changed stool caliber, diarrhea around menstruation, difficulty wiping, constipation during travel, or the extent to which bowel symptoms are interfering with work and social life. Pasricha’s repeated message was that gastroenterologists hear these concerns constantly. A patient who says they poop their pants a few times a month, for example, is not describing something beyond clinical experience; she said that in older adults, doing so once or twice a month on average is common.

Torres made the same point in practical terms when he noted that gastroenterologists are not offended by specificity. Pasricha encouraged patients to bring photographs if a picture communicates the issue more clearly than awkward description. Gastroenterologists chose this work; embarrassing bowel symptoms are routine in clinic. If a patient is struggling to describe whether something is “bright red” or “fuchsia,” a photo can get to the point faster. Her caution was practical: use private communication with a physician, not social media or direct messages.

The professional obligation, in Pasricha’s view, is to make the conversation easier so that useful details come out: frequency, effort, form, change, pain, bleeding, social disruption, medications, diet, travel, and stress. Once those details are speakable, they can become clinically actionable.

Trisha Pasricha’s central nutrition argument was that fiber is not merely roughage and not only a “gut health” intervention. It is a way of feeding the microbiome, with consequences she framed as body-wide.

Most Americans, she said, are not getting enough. She gave the figure as 95% of Americans missing fiber goals. Those amounts are easy to miss. A processed breakfast cereal, a ham sandwich, and chips can leave someone at dinner still needing to make up a large fiber deficit.

The reason to care is microbial. Humans do not have the enzymes to break down fiber. The bacteria in the colon and small bowel ferment it. Pasricha described more than a trillion bacteria living there, with different species depending on different types of fiber. When microbes ferment fiber, they produce short-chain fatty acids, including butyrate. Those compounds can be absorbed into the bloodstream and travel to organs including the heart and brain, where Pasricha said they may provide anti-inflammatory effects that the body cannot generate the same way without microbial help.

Her own framework for eating for the microbiome has three parts. First, meet fiber goals “by any means necessary.” Second, eat a diversity of plant-based fiber sources, because different species thrive on different fibers and microbial diversity is one hallmark she associates with a healthy microbiome. Third, eat at least one probiotic food a day.

For probiotic foods, she cited a randomized controlled trial from Stanford in which one group ate a high-fiber diet and another ate as many probiotic foods as they could for roughly eight to ten weeks. In the probiotic-food group, she said, microbiome diversity increased and 19 inflammatory proteins decreased in the bloodstream. She distinguished probiotic foods with live cultures — Greek yogurt, kefir, and similar foods — from fermented foods where the process changes the food but cooking may kill the bacteria. Sourdough bread may still be changed by fermentation, but for live-culture benefit she wants foods that still contain live organisms.

Pasricha is cautious about supplements generally, but she makes an exception for psyllium husk, a soluble fiber she takes on days when she does not meet her fiber goals through food. Once it reaches the stomach, psyllium forms a gel. It should be taken with water; she specified an eight-ounce glass. Cardiologists studied it before gastroenterologists, she said, because the gel binds bile salts. The liver then makes more bile salts by lowering cholesterol in the bloodstream, which can help people with high cholesterol.

Psyllium can help bind loose stool together, but it can also help soften hard stool. Pasricha called it a “shape shifter.” For patients with irritable bowel syndrome with diarrhea, she said the American Gastroenterological Association guidelines recommend psyllium, even though patients sometimes assume fiber will worsen diarrhea. Her distinction was soluble fiber: it can adapt to the body.

The studied dose she discussed was about 10 grams a day, but she warned against going quickly from no fiber to a high amount. One teaspoon of psyllium has roughly four to five grams of fiber. Starting too fast can cause bloating and gas. Her preferred approach is gradual: perhaps half a teaspoon for a week or two, then increase slowly by half-teaspoon increments while the body and microbes adjust.

Food can also be therapeutic. Pasricha singled out kiwis for constipation. Two randomized controlled trials, she said, have found that two kiwis a day are effective. Prunes still have evidence behind them, but head-to-head trials have found two kiwis a day as effective as psyllium husk and as effective as a large amount of prunes, with less bloating. Kiwis are also easier to recommend to college students than prunes. The peel is edible and contains fiber, though she said people do not have to eat it.

Protein trends received a more qualified response. Gastroenterologists, Pasricha said, “love fiber maxing” and feel “meh about protein maxing.” She was supportive when the protein focus leads people toward plant proteins such as lentils and legumes. But in general, she said, Americans are more likely to meet protein needs than fiber needs, though older adults may need more protein than they currently get. If she has to choose where to push attention, she chooses fiber.

Trisha Pasricha’s title claim — that people have been pooping wrong — is not only about diet. It is also about mechanics. The seated toilet position resembles the way people sit at dinner or at a desk, but she argued that it is not the position in which the body is best arranged to evacuate stool.

At the end of the colon, she explained, a sling-like muscle kinks the passageway. She likened it to the body stepping on its own hose. That kink is useful when sitting at work or moving through daily life; people do not want pressure constantly bearing down on the rectum. But when sitting on a toilet in the same upright posture, that kink remains. To straighten the passage, the knees need to rise above the waist.

Her evidence was partly anatomical and partly observational: toddlers, when they need to poop, drop into a deep squat. They are not following ergonomic advice; they are using a position that intuitively makes evacuation easier. Pasricha said she does not want to return to full squatting toilets herself, but she sees a simple adaptation: put something under the feet. It could be a branded toilet stool, a small stool, an Amazon box, or even a pair of high heels. The point is to elevate the knees.

This also ties into time spent on the toilet. Pasricha’s lab found that people who bring smartphones into the bathroom have about a 66% increased risk of hemorrhoids. Her explanation was not that the phone directly affects hemorrhoids, but that phones extend time on the toilet. Apps distract people in the bathroom the same way they do in bed or at dinner. Sitting longer on an open toilet seat without pelvic-floor support allows hemorrhoidal cushions to fill and become engorged.

Hemorrhoids themselves are not abnormal. Pasricha said everyone has them. Anatomically, they are cushions of veins near the top of the sphincters. She also noted that people have two sphincters, internal and external. Hemorrhoids serve a sensory function: they help the body distinguish gas from liquid stool, sending signals that allow a person to pass gas safely. They become a medical problem when they swell, bleed, hurt, or itch.

The practical guidance is therefore less about shame and more about duration and posture. Raise the knees. Do not camp out on the toilet. If squatting were required, Pasricha joked, nobody would spend an hour texting from the bathroom; people would get in and get out.

Travel changes bowel habits because it disrupts the colon’s routine at several levels. Trisha Pasricha described the colon as a “creature of habit.” Time-zone changes, altered sleep, long flights, and immobility all interfere with the rhythm that helps the colon contract at predictable times. Exercise stimulates contractions; sitting on a plane for hours removes that signal. Air travel also makes hydration harder, with passengers relying on small cups of water while the colon still needs fluid.

Then there is stress and context. Travel can mean family logistics, packed schedules, and unfamiliar bathrooms. Many people can only comfortably poop in what Pasricha called the “safe bathroom” at home. Work bathrooms are hard for some people; shared hotel rooms with relatives and thin privacy are harder.

Her advice is to rebuild routine deliberately. She takes a fiber supplement on vacation because she assumes she will not eat the same foods she eats at home and may not get enough fiber through meals. She recommends trying to eat “a real adult vegetable” every day if possible, while acknowledging that travel often makes that unrealistic.

She also recommends a sleep mask, not only for rest but for resetting the body’s clock. The aim is to behave as if one is already in the new time zone, helping the colon wake at the time one wants it to function. Morning cues matter. For Pasricha, coffee first thing is a priority when traveling because she knows it works for her. For someone else, it might be a morning walk. The point is to restore enough rhythm that the colon recognizes the routine.

Menstruation is another predictable source of change, though Pasricha noted that men in the room were far less likely than women to know about it. In younger women who menstruate, bowel habits can shift for two main reasons: hormones and prostaglandins. Progesterone before a period can contribute to constipation. During the period, prostaglandins that cause uterine contraction can also cause bowel contraction, leading to diarrhea at an especially unwelcome time. She added that perimenopause, menopause, and postmenopause can bring additional bowel changes that many people do not know to discuss.

Trisha Pasricha argued that many people treat the anal area as if it were tougher than it is. Toilet paper, especially one-ply, can be abrasive. She called two-ply “an act of self-love” and said one-ply can cause microtears in an area where nobody wants microtears.

Her stronger recommendation was a bidet. In the United States, the common version is not necessarily a separate European fixture but a nozzle attached to the clean water supply, or a replacement toilet seat that can include heat. She described the stream as gentle, not a “fire hose,” and said users tend not to look back.

The clinical cases that first made bidets important to her were patients with Parkinson’s disease. Some struggled physically to reach and wipe, which could require caregiver help for an embarrassing and intimate task. A bidet could restore some independence. She then saw broader usefulness: postpartum patients with soreness, women experiencing diarrhea during their periods, and people who simply feel wiping never cleans well enough.

Wet wipes received a narrower endorsement. They can be useful during short periods of frequent diarrhea, during colonoscopy preparation, or for people living with diarrhea-predominant IBS. They may be gentler than dry paper, though some contain chemicals that irritate skin. Pasricha’s main objection was environmental and plumbing-related: “flushable” wet wipes, she said, are not actually flushable. Her conclusion was that people concerned about skin care or environmental impact eventually end up on “team bidet.”

Colonics drew a much sharper response. Pasricha said her view was “strongly negative.” She worries they may disrupt the microbiome, though she called that concern hypothetical. More concretely, she worries about tears and perforation, which she has seen. She also questions the reason for doing them: what underlying concern is being treated, and are there more evidence-based ways to address it?

Flatulence is another area where Trisha Pasricha sees patients misjudging themselves because no one talks plainly about what is ordinary. People often worry they pass gas more than everyone else. If they keep a diary and report 10 times a day, she tells them that is normal. Average frequency, she said, is 10 to 20 times per day, and sometimes people are not aware they are doing it.

The gender comparison came from research by Michael Levitt, whom Pasricha described as a major figure in gastroenterology and an NIH-funded scientist who studied flatulence. Men tend to produce larger volumes of gas. Women tend to have more concentrated sulfur-containing compounds, which are responsible for odor. But because women’s volume is smaller and men’s volume is larger, sniff testers rated the overall intensity as roughly equal.

The key chemical fact in Pasricha’s explanation is that 99% of gas is odorless. The problematic 1% contains sulfur. That is why bismuth subsalicylate, commonly known as Pepto-Bismol, can be useful for specific situations where odor prevention matters. Pasricha said bismuth can neutralize more than 90% of sulfur-containing gases, though it has to be taken somewhat around the clock and started before the relevant event.

John Torres added the physician’s caution: use it in moderation. Pasricha specified that people with kidney disease or those taking daily aspirin should discuss it with their doctor.

Trisha Pasricha’s research specialty is neurogastroenterology, the study of the gut-brain connection. She said the field is relatively young as a named subspecialty, perhaps about 20 years old, though the connection itself has been recognized for more than a century.

For most of that time, the dominant frame was brain-to-gut: stress, anxiety, and central nervous system signals affecting digestion and bowel habits. Pasricha said that is real, but incomplete. The gut contains more than 500 million nerve cells, more than the spinal cord. This “enteric nervous system” is why she says the gut is a brain. In some organisms, she noted, the gut was the only brain-like decision-making system. Jellyfish, for example, do not have a visible brain in the head, yet make decisions about movement and eating.

Humans evolved connections between the brain in the head and the nervous system in the gut through bloodstream and hormone signaling, but Pasricha emphasized the vagus nerve. In the 1990s, she said, the field recognized that most vagus-nerve signaling between the gut and brain travels from gut to brain, not the other way around. That shift coincided with growing ability to sequence and understand the microbiome.

The implication, as Pasricha described it, was a reversal of familiar assumptions. Instead of asking only how stress and anxiety alter bowel habits, researchers began asking whether gut changes might contribute to depression, anxiety, and neurodegenerative disorders such as Parkinson’s and possibly Alzheimer’s. That is where her lab works.

Her most exciting research prospect is the possibility that, in her lifetime, colonoscopy or endoscopy could help predict Parkinson’s disease risk through a gastrointestinal biomarker. She does not expect this in the next five years and perhaps not in the next 10, but she thinks the field is moving toward it.

The rationale, in Pasricha’s account, is that many people with Parkinson’s have gastrointestinal symptoms years, even decades, before motor symptoms. Studies, she said, suggest that for some people — not everyone — the misfolded protein involved in Parkinson’s begins in the gut and travels upward, potentially through the vagus nerve. Her lab found that people with a history of ulcers had a 76% increased risk of developing Parkinson’s disease. To her, that is frightening but also clinically promising: if the process begins in the gut, there may be a years- or decades-long window to intervene before it reaches the brain.

Trisha Pasricha separated probiotic foods from probiotic supplements. She eats probiotic foods daily, but said probiotic supplements are not generally recommended by gastroenterologists for most conditions under academic guidelines because the evidence is not strong enough. That may change, but she said current data do not support the broad claims often made for supplements.

That matters especially around antibiotics. Many people instinctively take probiotic supplements while on antibiotics to protect or restore the microbiome. Pasricha said the evidence has not borne that out. Antibiotics can disrupt the microbiome, but she said the strongest data on long-term concern is in children, especially ages zero to five, when the microbiome is most malleable. In adults, antibiotic courses usually cause temporary changes, with the microbiome often returning toward baseline within about two weeks.

There are exceptions. Pasricha referred to a recent study in Nature or a Nature journal showing that some “heavy hitter” antibiotics can have detectable microbiome effects even up to eight years later after a single course. She stressed that this is not what happens to most people.

Her practical response after antibiotics is not a special supplement protocol. She does the same things she does anyway: fiber, diverse plant foods, and probiotic foods. She did not claim a special protocol; she framed the response as applying general principles she already follows.

GLP-1 medications received a more favorable interpretation than many patients expect from a gastroenterologist. Pasricha said GI clinicians often like GLP-1s because of protective associations. Her lab, she said, published findings earlier in the year associating GLP-1s with reduced risk of ulcers and damage to the gastrointestinal lining. She also said there is now substantial data associating them with reduced risk of colorectal cancer and about 13 cancers in total. Because those findings are independent of weight loss in her account, she suspects anti-inflammatory properties may be part of the benefit. Her lab is trying to understand possible roles for dopamine signaling and other neurotransmitters in the gut.

That does not mean she dismisses side effects. GLP-1s can cause nausea and constipation because they slow gastrointestinal movement. Pasricha’s approach is to anticipate those effects rather than treat them as a reason to avoid the medication automatically. She often starts patients on a fiber supplement preemptively, “to prime the pump,” and watches what happens over the next few weeks. Side effects are often worst during dose escalation and tend to subside within the first week or two, though not for everyone. For many patients, she said, support through that period may allow them to remain on a medication with broader long-term benefit.