Insight | Bloating, Constipation and IBS: What Four Doctors Try First

The Short Version

The four doctors here begin with the same question, how often and how completely you go, and the same aim, a bowel movement every day [1][2][4][5]. Gastroenterologist Robynne Chutkan's first moves are hydration, movement and plant fiber, plus a hard look at every pill you take [1]. Rajsree Nambudripad, an integrative physician with gastroenterology training, starts everyone on bedtime magnesium, a ginger-based motility supplement and digestive enzymes while tests are pending [2]. Gastroenterologist Brennan Spiegel calls exercise the most effective therapy for IBS and adds posture and core strength [3]. Gynecologist Sara Gottfried treats constipation as a warning sign that should prompt questions about stress, thyroid and hormones [4][5]. Movement is the one step all of them share; they differ on supplements, on water and on how fast to add fiber.

What They Said

Robynne Chutkan: water, movement, fiber, and the medicine cabinet

Robynne Chutkan, a gastroenterologist on the Georgetown faculty, was asked which three small habits she would give someone with bloating, IBS or constipation. Her answer: "it's hydration, it's movement and it's fiber." [1]

Movement comes with a mechanism. It stimulates peristalsis, the contractions of the gut's smooth muscle, and creates nitric oxide [1]. When contents do not move through in time, she says, the result is bloating, constipation and bacterial overgrowth [1]. Her evidence is clinical: the worst gut problems she sees are in nursing homes, and of those patients she says, "It's because they're not moving." [1] She adds that many people became sedentary during the pandemic, herself included [1].

On water, she calls the gut plumbing that needs unclogging. Her rule of thumb is at least half your body weight in ounces of plain water daily, without flavorings or electrolytes that can irritate the gut [1]. She estimates, and calls it a generalization, that about half of the bloated and constipated people she sees in her office improve once they hydrate properly [1].

Fiber, for her, means plants more than powders. She cites the American Gut Project, a study of more than 10,000 people, in which the diet's label did not matter but eating 30 or more different plant foods a week did [1]. It can be as simple as grabbing a carrot on the way out the door [1]. She is skeptical of probiotic supplements for the average healthy person and enthusiastic about fermented foods such as sauerkraut and kimchi [1].

Then comes the detective work, which she does before reaching for treatment. For IBS and constipation she sorts possible causes into four groups [1]. The first is mechanical: fibroids, endometriosis, a tilted uterus, prolapse or scar tissue [1]. The second is the medicine cabinet, including prescriptions, over-the-counter drugs and supplements [1]. Side effects are listed most common first, she explains, so if nausea, constipation or diarrhea is near the top of the list and you have it, that is worth raising. She is clear that this means a conversation and not stopping on your own: "talk to the prescriber." [1] The biggest culprit she names is the NSAID class, such as ibuprofen, which she says is the leading cause of emergency visits for gastrointestinal bleeding [1]. The third group is hormones, including undiagnosed hypothyroidism and perimenopause [1]. The fourth is motility problems tied to the microbiome, including antibiotics taken years earlier [1].

Her image for why the review comes first: "you can't fill a bathtub with the stopper out" [1]. Good habits will not help if a drug or food is draining the benefit away.

She adds two things patients often miss. One is that a daily bowel movement does not rule out constipation. If evacuation is incomplete, which she says often shows up as a smeary wipe, you are still backed up, and many bloated people are constipated without knowing it [1]. The other is a learned holding pattern. People who held it in as children because of unpleasant school bathrooms, more often girls, can train the external sphincter to clench just when the internal one relaxes: "You're clenching when you should be releasing." [1] A clue is that more fiber and water make the person more bloated, and her recommendation is biofeedback physical therapy or cognitive behavioral therapy [1].

She also explains why women are affected more: a colon three to five inches longer on average, a deeper pelvis where the colon competes with the uterus, ovaries and bladder, and a less tight abdominal wall [1]. For a healthy person who returns from vacation bloated, she likes two days of clear liquids with about a quarter bottle of liquid magnesium citrate at night, after confirming there is no kidney disease, in place of harsh stimulant laxatives [1]. To tell bloat from fat, measure your waist at the belly button morning and night for a week; bloat varies and fat does not [1].

Rajsree Nambudripad: start motility and digestion before the tests return

Rajsree Nambudripad is board certified in internal medicine and integrative medicine and trained in gastroenterology [2]. She came to her protocol through her own illness: bloating that spread from gluten and dairy to nearly every food until she concluded, "the problem wasn't the food. The problem was my gut." [2]

Her model is a garden with four systems: motility as the irrigation, the stomach acid, enzymes and bile that break food down, the gut lining as the soil, and the microbiome as plants and weeds [2]. Many of her patients have had normal endoscopies and colonoscopies and still do not feel normal, which she attributes to one or more of these systems being off [2].

Her first step does not wait for a diagnosis. With every patient, at the first visit and while tests are pending, she starts the first two systems [2]. For motility, magnesium at bedtime, since the citrate form draws water into the colon as a gentle osmotic laxative, plus a ginger and artichoke supplement that she says activates the gut's overnight cleaning waves [2]. For digestion, high-potency digestive enzymes with meals, or without supplements, water with lemon juice or a little apple cider vinegar [2]. She reports that at the second appointment, about a month later, patients often tell her they are more than 50% better [2].

For bloating her opening question is the same as Chutkan's: "The first thing I always ask my patients is how are your bowel movements?" [2] If someone goes only every three or four days, that backup is the problem and it gets fixed first [2]. How often should you go? "Every day." [2] If magnesium and the motility aid are not enough, she escalates for a limited time to a natural stimulant laxative such as dried aloe leaf, with the goal of returning to the basics [2].

"Gas itself is not the problem," she says; it becomes one when it is trapped, usually from poor motility, poor breakdown of food, or bacteria in the wrong place [2]. For fast relief she suggests digestive enzymes, the motility supplement, nightly magnesium, and a walk instead of sitting at a desk [2].

On IBS she is direct: "IBS is just a label for your symptoms," and not their cause [2]. She cites a figure that about 70% of IBS is caused by small intestinal bacterial overgrowth, or SIBO, diagnosed with a three-hour lactulose breath test at home [2]. She says conventional antibiotic treatment "has a very high failure rate and a very high relapse rate" and so she works in four phases: motility, then digestion, then calming gut inflammation, and only then herbal antimicrobials [2].

Her eating habits differ from the usual fiber-and-water advice in two ways. She notes that many gut patients are fiber sensitive, so she starts slowly with well-cooked leafy greens and builds variety by trial and error [2]. And she advises against drinking a lot of water with meals, saving most of it for about 45 minutes later [2]. Her other daily habits are to space meals four to five hours apart without snacking, eat without devices, eat only when truly hungry, and move after meals [2].

She links constipation to the thyroid, since low thyroid slows motility, and says any constipated patient should have thyroid labs checked [2]. For finding help, she suggests starting with a gastroenterologist to rule out structural problems such as colon cancer, inflammatory bowel disease and celiac disease [2].

Brennan Spiegel: exercise, posture and the back

Brennan Spiegel, a gastroenterologist at Cedars-Sinai, puts movement first without qualification. Exercise, he says, is "the most effective therapy we have for IBS, by far," and he cites randomized controlled trials of tai chi, yoga, osteopathic interventions, strength training, swimming and running, while stressing it is not the only treatment [3].

His reasoning is structural. When he sees someone with IBS he asks about their back, and most report back pain [3]. A weak back, in his account, leads to a compressed gut [3]. Slouching over a phone or desk rolls the shoulders forward, drops the chest and diaphragm and compresses the abdomen; he compares a slouching gut to a kinked garden hose that backs up [3]. Engaging the muscles between the shoulder blades lifts the chest and opens the abdomen, which he says is better for digestion [3].

His own discovery came from watching his mother-in-law, who spent most of the day lying flat in assisted living and soon developed slow digestion, stomach pain and low mood with no change in diet or medication [3]. It is the same observation Chutkan makes about nursing homes [1][3].

He offers a quick check for one group. People who can bend a pinky far past 90 degrees or touch thumb to forearm are hypermobile, and he suggests their internal supports may be stretchy too, letting the gut sag; he advises seeing a doctor and strengthening the abs, core and upper back, with swimming a good choice [3]. He recommends roughly 10 to 13 glasses of water a day, and a slow breath that begins in the abdomen to shift the body toward rest-and-digest [3]. His message to people who blame themselves: "it's not your fault." [3]

Sara Gottfried: constipation as a signal

Sara Gottfried is a gynecologist, and she reaches the gut through hormones. About 80% of the women she treats tend toward constipation [4][5]. She rejects the definition she was taught in training, fewer than one bowel movement every three days, and uses her own: anything less than a bowel movement every morning with a feeling of complete evacuation [4][5].

She gives the reasons she sees it so often in women. Borderline thyroid function that no one has flagged, high perceived stress, and an imbalance between estrogen and progesterone all push toward constipation, and women's colons are longer and more often twisted [4][5]. Her blunt summary is that "being female is a health hazard." [4] She cites twice the rate of depression and insomnia and five to eight times the risk of thyroid dysfunction in women [4][5]. Stepping away from the science, as she says, she wonders whether part of it is the physiology of having to control and hold things in, and concludes that constipation "is a really important signal to pay a lot of attention to." [4][5]

The gut also matters to hormones in the other direction. A subset of gut bacteria she calls the estrobolome regulates estrogen; when certain bacteria make too much of an enzyme, estrogen that should be eliminated is recirculated [4][5]. Chutkan describes the same system and warns that long-term antibiotics can disturb it [1]. Gottfried's food advice is vegetables above supplements, by smoothie if necessary, and like Chutkan she is underwhelmed by probiotics outside specific uses [4][5].

Her remedy for the stress part is precise: "I'm not a fan of lowering stress. I'm a fan of lowering perceived stress," [4]. She uses a menu of tools including meditation, yoga and breathwork, and she and Andrew Huberman agree that regular bowel habits reflect the balance between rest-and-digest and fight-or-flight [4][5]. She also criticizes siloed care, in which a woman with constipation, fatigue and autoimmunity is sent to three specialists who rarely talk to each other [4][5].

Where They Agree, and Where They Don't

They agree on the target. Chutkan, Nambudripad and Gottfried each say a healthy gut empties every day, and both Chutkan and Gottfried dismiss the textbook threshold of three movements a week or one every three days [1][2][4][5]. Chutkan and Gottfried both add that evacuation should feel complete [1][4].

They agree bloating usually starts with constipation. Chutkan and Nambudripad ask about bowel movements first [1][2].

They agree on movement. Chutkan, Nambudripad and Spiegel all prescribe it, and Chutkan and Spiegel describe the same decline in people who lie or sit all day [1][2][3].

They agree that a name is not an explanation. Nambudripad calls IBS a label; Chutkan and Gottfried look for mechanical, drug, hormone and thyroid causes behind it; all three name the thyroid [1][2][4][5].

They agree stress acts on the gut. Chutkan says it diverts blood from digestion, Nambudripad wants meals eaten in a rest-and-digest state, Spiegel teaches a calming breath, and Gottfried works on perceived stress [1][2][3][4].

They part ways in four places.

Supplements. Chutkan's method removes things first and relies on food, water and movement, with magnesium citrate as an occasional reset [1]. Nambudripad starts every patient on nightly magnesium, a motility supplement and enzymes [2]. Chutkan's reason is that the medicine cabinet, supplements included, is often the cause [1]. Nambudripad's is that these products are safe long term in her experience and bring relief quickly while the search continues [2]. Neither cites a head-to-head trial.

Water. Chutkan sets a high daily target, and Spiegel recommends 10 to 13 glasses [1][3]. Nambudripad does not argue against hydration but moves most drinking away from mealtimes [2]. The advice can be combined.

Fiber. Chutkan urges plant variety from the start [1]. Nambudripad warns that sensitive guts need a slow start with cooked greens [2]. Chutkan gives a related warning from the other side: if more fiber and water make someone more bloated, a holding pattern may be the problem [1].

Testing. Chutkan and Spiegel act on history and habits first [1][3]. Nambudripad orders tests at the first visit, including a breath test for bacterial overgrowth, while starting the basics the same day [2]. Gottfried, from her specialty, would check thyroid and hormones [4][5]. Nambudripad's 70% figure for overgrowth in IBS is one she cites; the other doctors do not address it [2].

Why It Works

Movement drives the gut's own muscle. Chutkan's account is peristalsis and nitric oxide, with stasis leading to bloating and overgrowth [1]. Spiegel adds that an upright, strong trunk gives the gut room [3].

Water softens and moves contents. Chutkan's plumbing image covers it, and magnesium citrate works the same way by drawing water into the colon [1][2].

Fiber feeds the microbes. Chutkan says fiber is fermented into healthy metabolites, and the plant-variety finding supports variety over any one diet [1].

Drugs act on the gut directly. Chutkan explains that swallowed medicines can change the gut's acidity, lining and microbes, which is why side effects there are so common [1].

Hormones and thyroid set the pace. Low thyroid slows motility [2]. Gottfried adds estrogen-progesterone imbalance and stress, and both she and Chutkan describe gut bacteria recycling estrogen [1][4][5].

The nervous system sets the mode. Digestion runs in the rest-and-digest state, which is why stress, rushed meals and holding it in all worsen symptoms [1][2][4].

The evidence offered is a mix: the American Gut Project and Spiegel's randomized trials of exercise on one side, and clinical estimates on the other, such as Chutkan's half of constipated patients improving with water and Nambudripad's patients reporting themselves 50% better in a month [1][2][3].

Where It Applies, and Where It Doesn't

These first steps suit everyday bloating, sluggish bowels and symptoms already labeled IBS in otherwise well people.

They do not suit warning signs. Chutkan lists blood in the stool, weight loss, vomiting, significant abdominal pain and unrelenting nausea as reasons to see a gastroenterologist quickly [1]. Nambudripad lists consistent blood in the stool, persistent vomiting and unexplained weight loss of more than 10 pounds, and wants structural disease ruled out first [2].

Some advice has conditions. Magnesium citrate is for people without kidney disease [1]. Stimulant laxatives such as aloe are for limited use [2]. Medication changes go through the prescriber [1]. More fiber and water can worsen bloating when the problem is a clenched sphincter or a fiber-sensitive gut [1][2]. Spiegel's gravity framework is his own theory, though his exercise advice rests on trials [3]. Gottfried's link between constipation and holding things in is, by her own description, opinion [4][5].

Persistent or severe symptoms, and any decision about medicines, supplements or testing, should be taken to a doctor.

What To Do With It

1. Check the red flags first: blood in the stool, weight loss, vomiting, significant pain or unrelenting nausea mean a prompt medical visit [1][2].
2. Take stock of your bowel habits. Aim for a complete movement every day, and treat less than that as worth fixing [1][2][4].
3. Move daily, and walk after meals or when bloated instead of sitting [1][2][3].
4. Drink more plain water; Chutkan's target is half your body weight in ounces a day [1].
5. Add plants gradually and for variety, working toward 30 different ones a week; if your gut is sensitive, begin with well-cooked greens [1][2].
6. Lay out every prescription, over-the-counter drug and supplement, read the side effects, and discuss any gut effects with the prescriber before changing anything [1].
7. If you and your doctor agree, try magnesium at bedtime, and consider digestive enzymes with meals [2].
8. Do not hold it in, and give yourself time and privacy; if more fiber and water make things worse, ask about biofeedback therapy [1].
9. Sit and stand tall, strengthen your back and core, and eat without devices so digestion happens in a calm state [2][3].
10. If constipation persists, ask for thyroid tests, and if you are a woman, raise hormones and stress as part of the same conversation [2][4][5].

Sources

1. Dr. Robynne Chutkan's Master Class on Gut Health, Bloating, IBS and Constipation · The Mel Robbins Podcast
2. Dr. Rajsree Nambudripad's Gut Garden Protocol for Bloating, IBS, SIBO and Reflux · The Mel Robbins Podcast
3. Dr. Brennan Spiegel on Gravity Intolerance: How Gravity Shapes Your Gut, Energy, Posture and Longevity · The Mel Robbins Podcast
4. Dr. Sara Gottfried on Female Hormone Health: Testing, Gut, Stress, PCOS, Contraception and Menopause · Huberman Lab
5. Dr Sara Gottfried How To Optimize Female Hormone Health For Vitality Longevity · Huberman Lab