Short answer?
Yes. Absolutely.
Long answer?
Stress doesn’t just live in your head. It lives in your gut.
As a colorectal surgeon, I see this pattern constantly: someone’s bowel habits are stable… they eat well, drink plenty of water, and exercise… then life happens. Work pressure. Family stress. Travel. Illness. Anxiety. And suddenly they’re bloated, backed up, straining, or not feeling empty.
That’s not coincidence. That’s science.
Your gut and brain are in constant communication through what we call the brain–gut axis. This bidirectional signaling involves:
The autonomic nervous system (nerves in your body)
The enteric nervous system (nerves in your gut)
The vagus nerve (nerve traveling from your brain to your gut)
Stress hormones like cortisol (signals that travel throughout your body)
When stress increases, your body shifts into sympathetic (“fight or flight”) mode.
Digestion is not a priority in fight-or-flight. Imagine you’re being chased by a lion. Your body shifts all the blood flow to your brain, heart, and leg muscles, so that you can run away. It’s not directing blood to your gut to help you digest.
So blood flow shifts. Motility changes. Muscle coordination alters. Rectal sensation gets wacky.
And for many people?
Bowel movements slow down.
Stress can affect bowel function in several ways:
-Slows Colonic Motility
Psychological stress alters colonic motor patterns and can reduce propulsive contractions, leading to delayed transit.
-Increases Pelvic Floor Tension
Anxiety increases muscle tone. That includes the pelvic floor.
If those muscles don’t relax properly, stool becomes harder to pass—even if it’s soft. Remember our previous posts– constipation is usually due to butt, or gut, or both.
-Alters Rectal Sensation
Stress can blunt the normal urge to defecate. People ignore signals or don’t feel them as clearly. Ignoring signals is soooo common. You’re a parent of young children and you’re rushing around to get dinner on the table while they’re melting down, throwing Legos at each other, and the baby is crying. You have to poop but IT WILL HAVE TO WAIT. Over time, your body says, well, she’s ignoring the signals, so we won’t bother her with this. Uh-oh.
-Changes Behavior
When people are stressed, we skip meals, change hydration, travel to a remote island nation, delay bathroom breaks, and sleep poorly. Poor sleep is related to constipation, too, which we will discuss in a separate post!
All of those behaviors worsen stool consistency and frequency.
In patients with Irritable Bowel Syndrome (IBS), the stress–gut connection is even stronger. Studies show stress can significantly alter bowel patterns in IBS-C (constipation-predominant IBS) through altered visceral sensitivity and motility regulation, which means the way that your body senses what’s going on in your bowels. In some cases, your body is hyperaware of everything going on in your bowels— hence, the irritable bowel.
But you don’t need IBS for stress to affect your bowels.
This happens in otherwise healthy individuals, too.
That sentence is common—and valid.
Temporary stress-related constipation is often new (never happened before), associated with a life event (that’s why I ask so many questions about what was happening when this started), and, the best news: reversible when stress improves!
Chronic stress, however, can reinforce a long-term pattern of hard stool, incomplete evacuation, and pelvic floor dysfunction.
Left unchecked, poop can snowball. Pun intended.
If stress is a contributor, treating constipation alone won’t fully solve it.
Helpful strategies include:
Regular toileting schedule— Most people go around the same time every day as long as you’re in your routine. But otherwise, remember The One Bowel Commandment! Go when you have to go, and don’t go when you don’t!
Optimizing your morning gastrocolic reflex- what does that mean? Drinking some warm water or eating something in the morning will kickstart your gut motility– that is why breakfast is the most important meal of the day.
Adequate hydration- 2L a day, or 3L when you’re stressed, working out, in a hot climate, or pregnant.
Targeted fiber (not just “more fiber”)- 25-35g of both soluble and insoluble fiber a day, and supplement if necessary
Pelvic floor physical therapy when indicated- we can evaluate this in the office
Stress regulation (breathing, exercise, sleep hygiene)— we will talk more about this!
And sometimes, yes—addressing anxiety directly. I talk to my therapist every other week and the brain catharsis translates into… gut catharsis.
The gut is not separate from the nervous system.
It is wired into it.
Stress can slow your colon, tighten your pelvic floor, dull your pooping urges, and change your stool.
Constipation isn’t always about fiber or water.
Sometimes it’s about your nervous system.
And that’s not “all in your head.”
It’s biology.
Until next time, that’s just the way the anus wrinkles.
