Why Can’t I Poop

Sometimes, a medical disorder like irritable bowel syndrome can cause constipation. Those issues often need care and treatment from your doctor. But for many people, the problem will be short-term and easy to fix. To figure out what has you stopped up, ask yourself these questions:

6 Sneaky Reasons You Can’t Poop

There are many things that can contribute to constipation. Here are six of them—and what to do about them.

Reviewed by Dietitian Maria Laura Haddad-Garcia Updated September 28, 2022

Being constipated is hard—to put it quite literally. And having to deal with the associated symptoms of bloating, abdominal pain and hard stools that are often painful to pass is even worse. But take comfort in knowing that you’re not alone. According to the U.S. Department of Health and Human Services, constipation—which is partially defined as pooping fewer than three times a week—affects 16 percent of American adults and doubles as we age. Approximately 33 percent of adults 60 and older deal with chronic constipation.

It’s important to know that constipation is not considered a disease, but a symptom of an underlying problem. Changes to your lifestyle, mental health and diet are just some of the reasons you may feel backed up. Here are six possible reasons you can’t poop, including tips from registered dietitians on what you need to do to help keep things regular.

poop emoji made of modeling clay

1. You May Be Dehydrated

From plump, elastic skin to increased energy levels, staying hydrated offers numerous benefits to our body’s various organs, including the digestive tract. In fact, according to the U.S. National Library of Medicine’s resource, MedlinePlus, not drinking enough water every day is one of the key reasons people experience constipation.

“At least a liter of water usually enters our colon during digestion, but only a small portion of that is excreted as part of our stool,” says Nashville-based registered dietitian Grace Goodwin Dwyer, M.S., M.A., R.D., L.D.N. “Poop that has had too much water removed from it, either because you’re dehydrated or because you’re pooping infrequently, is going to be pretty hard.”

Daily water intake requirements vary from one person to the next—with activity level and surrounding environment all playing a role in how much you need to drink. So while your recommended daily amount will vary based on these components, the Institute of Medicine of the National Academies does offer general recommendations for staying properly hydrated. For males, that’s achieved by consuming approximately 3.7 liters of total water per day (about 15 cups), and females, around 2.7 liters daily (about 11 cups). But your fluid intake doesn’t have to come from just plain ol’ water. Beverages—including juices, sodas, coffee, milk and tea—and food sources also count towards a person’s total water intake. (Psst—here are some of our favorite hydrating foods to help you meet your water goals!)

2. You’re Stressed and Feeling Anxious

Everybody experiences stress and anxiety differently. According to the Centers for Disease Control and Prevention (CDC), for some, stress can cause anxiety, fearfulness or feelings of helplessness. Others develop more physical responses, ranging from rapid heartbeat and dizziness to sleeplessness and, you guessed it, constipation.

“Stress can drastically influence our hunger, leading some people to emotionally eat and others to avoid eating,” says Kristen Carli, R.D., owner of Camelback Nutrition & Wellness, a private nutrition practice in Scottsdale, Arizona. “It can also greatly influence our gastrointestinal function.”

According to 2018 research published in the journal Frontiers in Microbiology, there’s a direct link between mental health and gut health. Chronic stress not only affects the gut microbiota but can also lead to the onset of digestive issues such as irregular bowel movements and irritable bowel syndrome (IBS). Stress can also result in the digestive process of peristalsis (wave-like movements that move food through your gut ) abruptly stopping as the body moves from a relaxed state into a fight-or-flight sympathetic nervous response, ultimately being a sneaky reason you can’t poop.

Learning what stress management techniques work for you can really help. “It can be as simple as relaxing in a bath with a glass of tea and a good book or more high intensity, like [an indoor cycling] class,” explains Carli. “I just guide patients on identifying what self-care activities appeal to them and suggest seeking these behaviors out instead of turning to food to cope with stress.”

3. You’re Not Eating Enough Fiber

Integral for balancing blood glucose levels, gut health and preventing the onset of chronic diseases, fiber is an essential macronutrient that we often overlook. In fact, if you’ve been struggling with constipation, Dwyer recommends assessing your daily dietary fiber intake levels. “It’s helpful to know what’s going on in our bodies, and sometimes boosting a specific type of fiber may help sort out a bowel movement issue.”

4. You’ve Had a Recent Change in Diet

Although upping your daily fiber intake will most likely be beneficial in the long run, a drastic change in diet can often result in short-term side effects—like constipation—as your gastrointestinal tract takes time to adapt. “If you do not eat much fiber and you suddenly consume lots of fiber, you will likely have some uncomfortable gastrointestinal symptoms, like bloating and gas,” explains Carli. “Start with 1/4 cup of legumes per day, for example, for a few weeks before increasing to 1/2 cup per day for a few weeks. Very slow increases will prevent these uncomfortable symptoms.”

Processed foods that are high in sodium, as well as high-fat, low-carb diets like the ketogenic diet, are also the culprits for irregular bowel movements. According to 2022 research published in the journal Nutrients, eating too much salt can decrease the amount of water in your poop, making it harder, and more difficult to pass.

“If you’re specifically struggling with constipation, I’d incorporate foods that have laxative effects, such as flax seeds, chia seeds, berries and stone fruits—peaches, plums, apricots,” adds Dwyer. “Start with 2 tablespoons for the seeds and 1 cup for the fruit per day. And, don’t forget that you’ll need to also increase your water intake to help your body move this fiber along.”

5. You Need to Up Your Exercise Routine

Your level of physical activity may be another reason you can’t poop on the regular. In addition to losing muscle strength, decreasing bone density and contributing to poor circulation, a sedentary lifestyle also increases the occurrence of irregular bowel movements, according to the National Library of Medicine’s resource MedlinePlus. Results from a 2019 review of the literature published in the Scandinavian Journal of Gastroenterology suggest that exercise may be a practical, effective treatment for constipation.

Exercise might also improve your gut’s microbiome. For example, results of a 2019 study published in Nutrients suggest a correlation between an increase in physical activity and the improvement of gut health. For healthy females above the age of 65, daily brisk walks were responsible for increasing intestinal Bacteroides, an essential type of microbiome bacteria.

6. You’re on a New Medication or Supplement

Too much of a good thing isn’t always a good thing, as is the case with food supplements. While iron and calcium are important nutrients required by the body for blood and skeletal health, having too much can slow down bowel functions, thus leading to constipation.

The same can be said for certain medications. According to a 2018 review of the literature in the journal Medicine, antihistamines, opioids, blood pressure medicines and even antidepressants, can all play a role in the regularity (or lack thereof) of your bowel movements. Some work by slowing down the time it takes for food to pass through the digestive tract, while others draw too much fluid from the GI tract. Both essentially increase the incidence of constipation, a risk that gets higher as we get older.

This is why healthcare providers and dietitians recommend increasing not just your dietary fiber levels, but your daily water intake as well. “I strongly urge people to remember that water is a part of this equation, too,” says Dwyer. “Many people who struggle with constipation are dehydrated and find that upping their fluid intake, especially in the morning, can make a world of difference.”

Why Can’t I Poop?

Can’t go? You’re not alone. About 20% of Americans have occasional constipation — bowel movements less than three times a week. Or if they do poop, the output is hard, small, and painful to produce.

Sometimes, a medical disorder like irritable bowel syndrome can cause constipation. Those issues often need care and treatment from your doctor. But for many people, the problem will be short-term and easy to fix. To figure out what has you stopped up, ask yourself these questions:

Is it time to fiber up? Moving your bowels regularly takes fiber — lots of it. We’re talking about 3 to 5 cups of fruits and vegetables every day. Go easy on meat and dairy and load up on produce. Just be sure you add it to your diet gradually. Skip fast and prepared foods. They may be quick and easy, but they’re almost always low in fiber.

How are my fluid levels? To move waste through your intestines, you gotta drink up! If you don’t drink enough water, you can get backed up.

Am I active? It’s as simple as this: Moving your body helps move your bowels, so too much time sitting can lead to trouble on the throne.

Are supplements the problem? Iron or calcium supplements can cause constipation in some people. It’s more likely with calcium carbonate supplements than with calcium citrate. If you take calcium or iron supplements, take extra care to eat enough fiber, drink plenty of water, and stay active. If that doesn’t help, talk to your doctor about other options to get you going or whether you can get these nutrients through your diet instead.

Am I stressed? When your brain’s stress response systems get flipped on, it causes changes in your body. The digestive system is especially sensitive to stress, and constipation can be one response.

Whether it’s for business or pleasure, travel is stressful. When it disrupts your regular routines, especially eating patterns, your pooping can get off-schedule as well.

Do I ignore the urge? Maybe you’re too busy to stop every time your body signals it’s time to poop. Maybe you don’t like using public restrooms, or any except your own at home. Here’s the problem with ignoring the urge: Sooner or later, you may stop feeling the signals.

Does pregnancy play a role? Overall, women get constipated more often than men. That’s especially true during pregnancy, when hormone changes can easily throw off your digestive system. Add the pressure a growing baby puts on your plumbing, and it’s no surprise you have trouble going. Problems with pooping are also common after childbirth.

What about my age? The chance of having trouble moving your bowels goes up as you get older, so make a point to get more exercise, drink more water, and eat more fiber.

Are my medications part of the problem? Pain relievers, iron supplements, some antidepressants, and diuretics are just a few common drugs that can have this effect. Also on the list are meds for diabetes and Parkinson’s disease, plus some blood pressure treatments. Over-the-counter medications like antacids can also stop things up.

Could it be a more serious problem? It’s rare, but possible. Discuss it with your doctor. If you’ve ruled out other causes, they may want to explore:

Problems with the muscles that squeeze your colon.
Hormone diseases like diabetes or an over- or underactive thyroid gland.
Diseases that affect the nerves around your colon or rectum, including multiple sclerosis, Parkinson’s disease, stroke, and spinal cord injuries.
Colon trouble. Tumors and other things that block your colon or rectum can prevent poop from moving out of your body.

Show Sources

National Institute of Diabetes and Digestive and Kidney Diseases: “Symptoms and Causes of Constipation,” “Eating, Diet, and Nutrition for Constipation,” “Definition and Facts for Constipation.”

New York State Department of Health: “All About Calcium Supplements.”

University of Utah Huntsman Cancer Institute: “Instructions for Starting Oral Iron Supplements.”

Arnaud, M. European Journal of Clinical Nutrition, December 2003.

UNC Center for Functional GI & Motility Disorders: “Stress and the Gut.”

Mayo Clinic: “Constipation: Causes.”