What Causes Constipation? A Complete Guide to Common Causes & What May Help

🟢 Introduction

Constipation is one of the most common digestive concerns.

For some people, it happens only occasionally—perhaps during travel, after a change in routine, or while taking certain medications.

For others, constipation becomes a frequent or long-term problem.

But what actually causes constipation?

The answer is often more complicated than simply “not drinking enough water” or “not eating enough fiber.”

Constipation can involve:

• Hard or dry stool
• Slow movement of stool through the colon
• Difficulty evacuating stool from the rectum
• Medications or medical conditions
• Diet and lifestyle factors
• Or a combination of several factors

Understanding what may be contributing to constipation can help guide a more appropriate approach.

🔵 First, What Does “Constipation” Actually Mean?

Constipation does not simply mean that you do not have a bowel movement every day.

Normal bowel frequency varies considerably from person to person.

Constipation may involve symptoms such as:

✔ Hard or lumpy stools
✔ Fewer bowel movements than usual
✔ Significant straining
✔ Difficulty passing stool
✔ A sensation of blockage
✔ Feeling that a bowel movement was incomplete

Some people may have bowel movements several times a week and still experience constipation symptoms.

Others may naturally go less frequently without significant difficulty.

👉 How comfortably and effectively you pass stool can matter just as much as how often you go.

💩 Stool Consistency Can Offer Useful Clues

The Bristol Stool Form Scale is commonly used to describe stool consistency.

It divides stool into seven general types:

Type 1: Separate hard lumps
Type 2: Lumpy, sausage-shaped stool
Type 3: Sausage-shaped with cracks on the surface
Type 4: Smooth, soft, sausage- or snake-like stool
Type 5: Soft blobs with clear-cut edges
Type 6: Fluffy or mushy pieces
Type 7: Watery stool

In general:

Types 1–2

Harder stools that are often associated with constipation.

Types 3–4

Generally considered well-formed stools.

Types 5–7

Progressively softer or looser stools.

But stool appearance alone cannot tell you why constipation is happening.

That distinction is important.

👉 If your stool is consistently hard, stool consistency may be part of the problem.

👉 If your stool is already relatively soft but remains difficult to evacuate, the problem may involve something other than stool dryness.

🧩 Constipation Often Has More Than One Cause

One of the most important things to understand is that constipation is not a single disease with a single cause.

For example, one person may have:

Low fiber intake + inadequate fluid intake + reduced activity

Another may have:

Opioid medication + hard stool

And another may have:

Soft stool + a natural bowel urge + difficulty coordinating the pelvic floor

All three people may say:

“I'm constipated.”

But the most appropriate approach may be completely different.

That is why simply telling everyone to “drink more water and eat more fiber” is not always enough.

🩺 Primary vs. Secondary Constipation: A Useful Distinction

Healthcare professionals may think about constipation in two broad ways.

Primary constipation

The problem is primarily related to bowel function itself.

Examples may include:

• Normal-transit constipation
• Slow-transit constipation
• Defecatory disorders

Secondary constipation

Constipation occurs in association with another factor, such as:

• A medication
• A medical condition
• Pregnancy
• Certain neurological or metabolic disorders

The distinction matters because simply treating the symptom may not address an important contributing factor.

For example, constipation associated with an opioid medication may require a different approach from constipation caused primarily by a defecatory disorder.

🌿 PART 1: Diet, Hydration & Daily Habits

🥗 1. Low Fiber Intake

Dietary fiber can influence stool bulk, consistency, and bowel function.

A diet consistently low in fiber may contribute to constipation in some people.

Fiber-rich foods include:

• Fruits
• Vegetables
• Whole grains
• Beans and lentils
• Nuts and seeds

Foods such as kiwifruit, prunes, pears, oats, chia seeds, and ground flaxseed can be useful sources of fiber and other components that may support bowel regularity.

But more fiber is not always the answer.

Some people experience increased bloating or discomfort when fiber is increased too quickly.

And if the primary problem is difficulty evacuating stool because of a defecatory disorder, simply adding more fiber may not solve the underlying problem.

👉 Increase fiber gradually and pay attention to how your body responds.

Related Reading: 10 Foods That May Help Relieve Constipation Naturally

💧 2. Inadequate Fluid Intake

Adequate hydration helps support normal stool consistency.

If fluid intake is insufficient, stool may become harder and more difficult to pass.

However:

More water is not always better.

If you are already adequately hydrated, drinking increasingly large amounts of water does not necessarily correct constipation.

The goal is adequate hydration, not forcing yourself to drink excessive amounts.

People with heart, kidney, or other conditions requiring fluid restrictions should follow their healthcare provider's recommendations.

👉 Related Reading: Why Am I Constipated Even Though I Drink Water?

🚶 3. Low Physical Activity

Physical activity supports overall health and may also support bowel regularity.

Long periods of inactivity can be associated with constipation, particularly in older adults and people with limited mobility.

Regular activity may include:

✔ Walking
✔ Gentle stretching
✔ Frequent movement breaks
✔ Exercise appropriate for your health and physical ability

You do not need an intense workout simply to support bowel health.

Even reducing prolonged periods of inactivity can be a reasonable part of a healthy bowel routine.

🚽 4. Repeatedly Ignoring the Natural Urge to Go

When stool reaches the rectum, your body may signal that it is time to have a bowel movement.

Repeatedly postponing a clear urge may sometimes make evacuation more difficult later.

Work schedules, travel, lack of privacy, unfamiliar bathrooms, or simply being too busy can interfere with normal bowel habits.

When reasonably possible:

Work with your body's natural signals rather than repeatedly overriding them.

✈️ 5. Changes in Routine, Travel & Environment

Constipation often appears when normal routines change.

Travel can combine several contributing factors:

• Different meal times
• Different foods
• Reduced fluid intake
• Long periods of sitting
• Less physical activity
• Unfamiliar bathrooms
• Delaying the urge because of inconvenience

This is why someone who normally has regular bowel movements may suddenly experience constipation while traveling.

👉 Related Reading: Constipation After Travel: Why It Happens and What Helps

💊 PART 2: Medications & Supplements

6. Certain Medications Can Cause or Worsen Constipation

Medication-related constipation is important—and sometimes overlooked.

Medications and supplements that may contribute include some:

• Opioid pain medications
• Anticholinergic medications
• Certain antidepressants
• Iron supplements
• Some calcium-containing products
• Certain blood pressure medications
• Other medications depending on the individual

Different medications affect bowel function in different ways.

Opioids, for example, can directly reduce gastrointestinal motility and are a well-recognized cause of constipation.

⚠️ Do not stop a prescribed medication on your own.

If constipation began—or became noticeably worse—after starting or changing a medication, talk with your healthcare professional or pharmacist.

Sometimes identifying a medication-related contributor is more useful than simply adding more fiber.

🩺 PART 3: Medical & Physiological Factors

🤰 7. Pregnancy and Postpartum Changes

Constipation is common during pregnancy and can also occur after childbirth.

During pregnancy, hormonal and physical changes may influence gastrointestinal function.

After childbirth, additional contributing factors may include:

• Reduced activity
• Changes in eating and drinking
• Pain or fear of straining
• Perineal soreness
• Recovery after C-section
• Iron supplements
• Opioid pain medications

👉 Related Reading: Why Is Constipation Common During Pregnancy?

👉 Related Reading:  How to Relieve Constipation After Vaginal Birth or C-Section (Gentle & Safe Guide)

🧠 8. Certain Medical Conditions

Constipation can sometimes occur in association with another health condition.

Examples include:

• Hypothyroidism
• Diabetes
• Certain neurological disorders
• Irritable bowel syndrome with constipation (IBS-C)
• Disorders involving the colon, rectum, or pelvic floor
• Other metabolic or systemic conditions

This does not mean that everyone with constipation has an underlying disease.

But persistent or unexplained constipation should not automatically be assumed to result from diet or dehydration.

If symptoms are new, persistent, worsening, or unusual for you, medical evaluation may be appropriate.

👵 What About Aging?

Constipation becomes more common with increasing age, but:

Getting older does not automatically mean constipation is normal or unavoidable.

Older adults are more likely to experience several factors that can contribute to constipation, including:

• Reduced mobility
• Multiple medications
• Changes in diet or fluid intake
• Neurological or other medical conditions
• Pelvic floor or evacuation problems

Therefore:

Constipation may become more common with age, but it should not automatically be dismissed as a normal part of aging.

Persistent constipation in an older adult deserves the same thoughtful evaluation as constipation at any other age.

👉 Related Reading:   Constipation in Older Adults: Why It Happens and Gentle Ways to Find Relief

🐢 PART 4: Sometimes Stool Moves Too Slowly Through the Colon

9. Slow-Transit Constipation

The colon normally moves digestive contents forward until stool eventually reaches the rectum.

In some people, movement through the colon is unusually slow.

This is sometimes called slow-transit constipation.

Possible features may include:

• Infrequent bowel movements
• Reduced natural urge to go
• Difficulty maintaining regular bowel movements
• Persistent constipation despite ordinary lifestyle measures

However:

Having infrequent bowel movements does not automatically mean you have slow-transit constipation.

Proper diagnosis may require medical evaluation and, in selected cases, testing of colonic transit.

This is another reason chronic constipation should not always be treated as simply a “fiber and water problem.”

🧠 PART 5: Sometimes Stool Reaches the Rectum—but Is Difficult to Get Out

10. Pelvic Floor Dysfunction & Defecatory Disorders

This is one of the most important—and least understood—causes of difficult bowel movements.

Having a bowel movement requires coordination.

Normally:

Abdominal pressure helps move stool downward → the pelvic floor and anal sphincter relax appropriately → stool can pass.

In some people, this coordination does not occur normally.

One example is dyssynergic defecation, a type of defecatory disorder.

Possible symptoms include:

• Significant straining
• A sensation of blockage
• Long toilet sessions
• Incomplete evacuation
• Feeling that stool is “right there” but will not come out
• Difficulty evacuating even when stool is relatively soft

This distinction matters.

If stool is already soft but evacuation remains difficult, simply:

drinking more water + eating more fiber + pushing harder

may not solve the problem.

For appropriately diagnosed defecatory disorders, specialized pelvic floor biofeedback therapy is an evidence-based treatment.

👉 Related Reading:  Why Do I Feel Like I Can’t Fully Empty My Bowels?

👉 Related reading: How to Relax the Pelvic Floor for Easier Bowel Movements

🧱 11. Structural Problems Can Sometimes Affect Evacuation

Less commonly, structural changes involving the rectum or pelvic floor may interfere with normal evacuation.

Examples can include:

• Rectocele
• Rectal prolapse
• Certain pelvic floor changes
• Other anorectal abnormalities

These conditions cannot be diagnosed simply from symptoms described on a website.

Persistent blockage, difficult evacuation, or incomplete emptying may require professional evaluation.

🚨 12. Severe Stool Retention or Fecal Impaction

Long-standing or severe constipation can sometimes progress to fecal impaction, in which a large mass of hardened stool becomes difficult or impossible to evacuate normally.

Fecal impaction occurs more often in certain higher-risk populations, including some:

• Older adults
• People with limited mobility
• People with neurological disorders
• People taking medications that significantly slow bowel function

Fecal impaction is more than ordinary constipation and may require medical treatment.

👉 Related Reading: When Constipation Becomes More Serious: Understanding Fecal Impaction

🧠 What About Stress?

The brain and gastrointestinal system communicate through complex neural, hormonal, immune, and behavioral pathways—often discussed as part of the gut-brain interaction.

Stress can influence gastrointestinal symptoms in some people, and conditions such as IBS are classified among disorders of gut-brain interaction.

But it is too simplistic to say:

“You are constipated because you are stressed.”

Stress may be one contributing factor, but persistent constipation deserves a broader look at diet, medications, bowel function, pelvic floor coordination, and medical conditions.

Relaxation and stress management can be useful parts of overall health, but they are not substitutes for evaluating persistent bowel symptoms.

🔄 Constipation Can Have Several Causes at the Same Time

This point is worth repeating.

Example 1

Opioid medication + reduced activity + hard stool

Example 2

Pregnancy + iron supplementation + changes in bowel routine

Example 3

Adequate hydration + soft stool + pelvic floor coordination problems

Example 4

Older age + limited mobility + multiple medications

This is why there is no single constipation remedy that works for everyone.

The right approach depends partly on what is contributing to the problem.

🌿 What May Help?

For uncomplicated constipation, a reasonable starting approach may include:

✔ Adequate hydration
✔ Gradually increasing appropriate dietary fiber
✔ Regular physical activity
✔ Responding to natural bowel urges
✔ Using a comfortable toilet position
✔ Avoiding prolonged or forceful straining
✔ Reviewing medications with a healthcare professional when appropriate

Some people may also benefit from evidence-based medications or other treatments.

And when a defecatory disorder is present, pelvic floor biofeedback or another targeted treatment may be more appropriate than simply adding more fiber.

👉 Related Reading: 10 Natural Ways to Support Easier Bowel Movements Without Straining

💡 What If I Feel the Urge but Still Can't Go?

This is particularly important.

If you already:

✔ Feel a clear bowel urge
✔ Feel that stool has reached the rectum
✔ Have relatively soft stool

but still experience:

• Significant straining
• A sensation of blockage
• Difficulty getting stool out
• Long toilet sessions
• Persistent incomplete evacuation

the problem may be more related to evacuation than simply stool formation.

Do not automatically assume that you need to drink more water, eat more fiber, or push harder.

Persistent symptoms may warrant evaluation for a defecatory disorder or another anorectal problem.

🌊 Where Does EaseFlow® Fit?

EaseFlow® is not designed to correct every cause of constipation.

It does not treat underlying conditions such as:

• Hypothyroidism
• Diabetes
• Medication-induced constipation
• Slow-transit constipation
• Pelvic floor dysfunction
• Bowel obstruction
• Other gastrointestinal or medical conditions

For appropriate individuals, however, a controlled warm-water bowel-care routine may provide additional support when stool has reached the rectum and evacuation is difficult or uncomfortable.

EaseFlow® is designed to provide:

✔ Controlled warm-water flow
✔ Adjustable flow
✔ No hanging gravity bag
✔ No forceful manual squeezing
✔ A convenient personal bowel-care routine

The goal is not to “flush out” the colon.

It is to support a more comfortable bowel-care routine while reducing unnecessary straining.

EaseFlow® does not replace evaluation or treatment of the underlying cause of persistent constipation.

🚫 Why Pushing Harder Is Not the Solution

Some abdominal pressure during a bowel movement is normal.

But repeated, prolonged, or forceful straining is different.

Excessive straining increases pressure in the abdomen, rectum, and pelvic floor and may contribute to or aggravate problems such as:

• Hemorrhoids
• Anal fissures
• Pelvic floor symptoms
• Rectal prolapse in susceptible individuals

If bowel movements repeatedly require significant force, it may be more useful to ask:

“Why is evacuation difficult?”

rather than:

“How can I push harder?”

👉 Related Reading: The Risks of Straining During Bowel Movements: What It Can Do to Your Body

🚩 When Should Constipation Be Medically Evaluated?

Occasional constipation is common.

But consider talking with a healthcare professional if constipation:

• Persists or progressively worsens
• Represents a significant new change in your usual bowel pattern
• Regularly requires substantial straining
• Causes frequent blockage or incomplete evacuation
• Does not improve despite reasonable measures
• Significantly interferes with daily life

Seek prompt medical attention if constipation is accompanied by:

• Severe or worsening abdominal pain
• Persistent vomiting
• Marked abdominal swelling
• Inability to pass stool or gas with worsening symptoms
• Significant rectal bleeding or blood in the stool
• Unexplained weight loss
• Fever or other concerning symptoms

Do not assume these symptoms are simply ordinary constipation.

🔵 Final Thoughts

Constipation is rarely as simple as “not enough water” or “not enough fiber.”

For some people, lifestyle factors are important.

For others, the problem may involve medications, another medical condition, slow movement through the colon, or difficulty coordinating the muscles involved in evacuation.

And sometimes several factors occur together.

Understanding the pattern matters.

If stool is hard, improving stool consistency may help.

If stool moves slowly through the colon, the approach may be different.

If stool is already soft and has reached the rectum but still will not come out easily, the problem may involve evacuation rather than hydration.

Better bowel care begins with understanding what is making the bowel movement difficult—not simply pushing harder.

🔗 Related Reading

👉  10 Natural Ways to Support Easier Bowel Movements Without Straining

👉 10 Foods That May Help Relieve Constipation Naturally

👉Why Is My Stool Dry Even When I Drink Water? (Blood Deficiency Constipation Explained)

👉 Why Do I Feel Like I Can’t Fully Empty My Bowels?

👉 How to Relax the Pelvic Floor for Easier Bowel Movements 

👉  Constipation in Older Adults

👉  When Constipation Becomes More Serious: Understanding Fecal Impaction

👉  The Risks of Straining During Bowel Movements: What It Can Do to Your Body

👉 Explore our complete Constipation Relief Guide to learn more about gentle approaches to supporting easier, more comfortable bowel movements.

👩⚕️ Designed With Care

EaseFlow® was developed by Lei Zhang, L.Ac., PhD in Traditional Chinese Medicine, drawing on more than 20 years of clinical experience and personal experience with difficult bowel movements following C-section.

👉 Learn more about the story behind EaseFlow®.

📚 References

1. Alavi K, Thorsen AJ, Fang SH, et al.
The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Evaluation and Management of Chronic Constipation.
Dis Colon Rectum. 2024;67(10):1244–1257.
PMID: 39250791.
View this guideline on PubMed

This guideline covers the evaluation and management of chronic constipation, including dietary measures, colonic transit, evacuation disorders, biofeedback, and other treatment approaches.

2. Bharucha AE, Lacy BE.
Mechanisms, Evaluation, and Management of Chronic Constipation.
Gastroenterology. 2020;158(5):1232–1249.e3.
PMID: 31945360.
View this review on PubMed

This review is particularly useful for understanding different constipation mechanisms, including normal-transit constipation, slow-transit constipation, and defecatory disorders.

3. Chang L, Chey WD, Imdad A, et al.
American Gastroenterological Association-American College of Gastroenterology Clinical Practice Guideline: Pharmacological Management of Chronic Idiopathic Constipation.
Gastroenterology. 2023;164(7):1086–1106.
PMID: 37211380.
View this guideline on PubMed

This guideline evaluates evidence for fiber and established pharmacological treatments for chronic idiopathic constipation.

4. Rao SSC, Benninga MA, Bharucha AE, Chiarioni G, Di Lorenzo C, Whitehead WE.
ANMS-ESNM Position Paper and Consensus Guidelines on Biofeedback Therapy for Anorectal Disorders.
Neurogastroenterol Motil. 2015;27(5):594–609.
PMID: 25828100.
View this guideline on PubMed

This consensus guideline supports biofeedback therapy for appropriately diagnosed dyssynergic defecation.

⚠️ Medical Disclaimer

This article is for educational purposes only and does not constitute medical advice, diagnosis, or treatment.

Constipation has many possible causes, and treatment should be individualized. Persistent, worsening, or unexplained bowel symptoms should be discussed with a qualified healthcare professional.

Seek prompt medical attention for severe or worsening abdominal pain, persistent vomiting, marked abdominal swelling, inability to pass stool or gas with worsening symptoms, significant bleeding, or other concerning symptoms.