Constipation: causes, symptoms, and how to improve your bowel function

Constipation is one of the most common digestive complaints out there — infrequent bowel movements, hard stools, bloating, or that frustrating feeling of not quite finishing the job. It's also more common than most people admit out loud: according to a large systematic review and meta-analysis, functional constipation affects an estimated 10-15% of adults, depending on which diagnostic criteria are used, and symptoms that drag on tend to take a real toll on quality of life.

Low fiber intake gets most of the blame, but it's rarely the whole story. Dehydration, a sedentary routine, stress, certain medications, underlying health conditions, and shifts in gut microbiota can all play a role. That's why it pays to look beyond quick fixes and understand what might actually be driving the problem.

Gastroenterologists commonly rely on the Rome IV criteria to define constipation, which can include:

• Less frequent bowel movements than usual

• Hard or lumpy stools

• Straining during defecation

• A feeling of incomplete evacuation

• Bloating or a feeling of heaviness

Constipation rarely has just one cause. More often, it's a combination of several interconnected factors working together.

Fiber adds bulk to stool and helps keep bowel movements regular. Too little of it in the diet, and stools can become harder and more difficult to pass. Adequate fluid intake matters just as much – when the body lacks fluids, stools can become drier and harder to move along.

Physical activity matters for more than overall health – it also supports normal bowel function. Long stretches of sitting and limited movement can slow gut motility, which is why some people notice bowel movements becoming less frequent or more difficult when they're less active.

The digestive system is closely tied to daily routine. Travel, a disrupted schedule, poor sleep, or heightened stress can all affect bowel function – which is exactly why constipation tends to show up more during holidays, business trips, or particularly hectic stretches of life.

Certain medications can also bring on constipation. The ones most often mentioned include some pain relievers, iron supplements, antidepressants, and blood pressure medications. If symptoms started after beginning a new medication, it's worth checking in with a doctor or pharmacist.

Gut microbiota – the collective community of microorganisms living in the digestive tract – has increasingly been linked to constipation. A growing body of research shows that its composition in people with constipation can differ from that of people with regular bowel movements.

The thinking is that microbiota can influence gut motility and how often you go, so shifts in its composition may, in some cases, be tied to altered bowel function. Microbiota isn't the sole cause of constipation, but it's considered one of several contributing factors.

This has scientists exploring different ways to support microbiota balance, including prebiotic fibers and probiotics. Some studies have evaluated the effect of probiotics on people with constipation, and while results varied by bacterial strain, certain probiotics were linked to more favorable bowel movement outcomes.

If you're curious about products for gut microbiota and digestive comfort, you'll find more of them in our gut health supplements category.

When you're constipated, you want relief now, not a lecture about long-term diet changes. Fair enough – while diet and lifestyle changes matter in the long run, a few things can help take the edge off faster.

Adequate fluid intake is essential for normal bowel function – without enough water, stools can become harder and more difficult to pass. This matters even more when you're increasing fiber intake. A commonly cited guideline is about 30-35 ml of fluid per kilogram of body weight per day, though individual needs can vary depending on physical activity, ambient temperature, and other factors.

Physical activity can help maintain normal bowel function, making it one of the first things worth trying. Beyond walking, gentle exercises that engage the abdominal and pelvic area can help – think squats, torso twists, or bringing the knees to the chest while lying down. Even a short burst of movement is often more beneficial than prolonged sitting.

Repeatedly putting off a bowel movement can make it harder to keep a regular rhythm going. When you feel the urge to go, it's best not to ignore it.

A handful of foods and herbs come up again and again when people talk about faster relief from constipation.

Prunes are one of the most frequently mentioned natural remedies for constipation. They contain fiber and other compounds that can help support regular bowel movements. Scientific studies have linked prune consumption to more favorable bowel movement frequency in people with constipation.

Kiwis have also drawn attention in recent years. Some research data suggests their consumption may be associated with more frequent bowel movements and softer stool consistency, though as with most foods, the effect can vary from person to person.

Senna, cascara, buckthorn, and rhubarb have a long history of use for infrequent bowel movements. They contain compounds associated with stimulating intestinal motility, and are typically noted for:

• can stimulate intestinal motility;

• traditionally used for short-term relief of constipation;

• more often used episodically, not daily.

Despite their long history of use, they're not recommended for extended periods without guidance from a specialist.

Diet is one of the biggest factors influencing bowel function. Healthy eating guidelines consistently emphasize that adequate fiber intake is a key part of a balanced diet, so it's worth checking whether you're getting enough of it day to day.

Research suggests a higher fiber intake can benefit people with constipation, particularly when it comes to bowel movement frequency. That said, fiber should be increased gradually and paired with plenty of fluids. It doesn't work identically for everyone, so results can vary from person to person.

Among the various types of fiber, prebiotic fibers stand out. One of the best known is FOS (fructooligosaccharides) – a fiber that isn't digested in the small intestine and instead reaches the large intestine, where it becomes food for beneficial bacteria. FOS differs from many other fibers in that it:

• acts as food for gut bacteria;

• can promote the growth of beneficial bacteria;

• contributes to microbiota diversity;

• can help support regular bowel movements

Scientific studies look at FOS not just for its effect on the microbiota, but also for its potential impact on bowel movement frequency and stool consistency.

It's worth paying attention to a few food groups that can help you rack up more fiber and support normal bowel function.

Vegetables, fruits, and berries are among the top sources of fiber. Many also contain natural water content, which, together with fiber, can help support normal bowel function. Adding more variety of plant-based foods to your daily diet usually boosts overall fiber intake.

Beans, lentils, chickpeas, and other legumes are among the richest sources of fiber. They can meaningfully boost total fiber intake, but like other fiber sources, it's best to increase them gradually.

Whole grain products naturally contain both soluble and insoluble fiber. Oats, whole grain bread, buckwheat, or brown rice can all be a useful part of a varied diet for getting more fiber.

Fermented foods like kefir, plain yogurt, or fermented vegetables can round out a microbiota-friendly diet. Their effect on constipation specifically varies, but they're commonly included in general gut health recommendations.

Flax seeds can be helpful for constipation thanks to their soluble and insoluble fiber. They can add bulk to stool and support regular bowel movements. Chia seeds come up in a similar context, since they're also a solid fiber source. Both can easily be stirred into yogurt, kefir, porridge, or other foods.

Some plants are linked more to overall digestive comfort than to bowel motility specifically. The most frequently mentioned include:

• Fennel;

• Peppermint;

• Lemon Balm;

• Cinnamon;

• Mallow;

• Dandelion.

These plants are traditionally used to support digestive comfort, most often mentioned in the context of easing bloating, that heavy feeling after meals, or general digestive discomfort.

Of all these plants, peppermint has the most scientific data behind it for easing certain digestive symptoms, particularly in irritable bowel syndrome.

You'll also find combination formulas on the market that pair prebiotic fibers with traditionally used digestive-comfort plants – often featuring FOS alongside ingredients like fennel, peppermint, lemon balm, or cinnamon. One example is the gut-support food supplement Le Dieci Erbe Flor.

If constipation keeps coming back, it's worth looking not just at what you're eating, but at what you might be overdoing. Heavily processed foods, low-fiber snacks, lots of sweets, and a diet light on fruits, vegetables, and whole grains can all make it harder to get enough fiber.

If constipation doesn't budge despite quick remedies and diet or lifestyle changes, or if it keeps coming back, it's a good idea to see a doctor.

Don't wait to seek care if it's also accompanied by:

• blood in stool;

• unexplained weight loss;

• severe or recurrent abdominal pain;

• anemia;

• sudden changes in bowel habits.

Bottom line: if constipation lingers for more than a few weeks, or any of the warning signs above show up, see a doctor to help identify what's actually going on.

Constipation usually comes down to a mix of factors – diet, dehydration, low physical activity, stress, or changes in gut microbiota. Certain foods, natural remedies, or lifestyle tweaks can offer short-term relief, but long-term, what matters most is enough fiber, a varied diet, proper hydration, regular movement, and habits that support a healthy gut microbiota. If symptoms keep coming back or won't go away, it's worth seeing a doctor.