Irritable Bowel Syndrome: Symptoms and Causes

Irritable bowel syndrome can be a major inconvenience to affected individuals. Without proper intervention, patients can easily suffer depression, social anxiety, and even fecal incontinence. Diagnosing IBS is the key to managing its symptoms. 

So, how is IBS diagnosed in a patient? Although there are definitive causes for irritable bowel syndrome, specific symptoms are used to properly diagnose this disorder. These include abdominal pain, changes in bowel habits, and changes in the appearance of bowels

In this article, we discuss everything you need to know about IBS — from diagnosis, symptoms and causes, to the myths surrounding this syndrome. 

What is Irritable Bowel Syndrome? 

Irritable bowel syndrome, also called IBS, is a common syndrome affecting up to 20% of people in the U.S, and occurs more commonly in women than men. A study suggests that women are more susceptible to gastrointestinal problems, including IBS, because the brain signals responsible for digestion are less responsive and more easily disrupted in women. 

IBS describes a host of symptoms that include constipation, diarrhea, change in frequency and consistency of bowel movements, and abdominal pain. Symptoms of IBS are episodic and can go away and resurface indefinitely. Irritable bowel syndrome is a chronic condition that can easily be managed through dietary, medical, and sometimes psychological intervention.

Early detection is crucial to ensure that your condition is treated before it becomes irreversible.  At Gastro Center NJ we perform routine tests and certain procedures, including colonoscopy and upper endoscopy.

Are IBS and Diarrhea the Same?

woman going to the toilet with toilet paper in her hand

Some people believe that IBS and diarrhea are interchangeable terms. In reality, IBS is a syndrome that triggers a host of symptoms due to a sensitive colon, which includes diarrhea. Although chronic in nature, IBS is a syndrome that can easily be alleviated with proper dieting and exercise. Symptoms can be soothed with appropriate lifestyle choices.

On the other hand, diarrhea is often acute and occurs as a result of a stomach infection, food intolerance, or medicine overuse. Although there are cases of chronic diarrhea, this alone is not considered a syndrome, and is often linked with a pre-existing condition such as inflammatory bowel disease (IBD). 

Irritable Bowel Syndrome VS Inflammatory Bowel Disease 

IBS and IBD are completely different conditions. IBS is what is considered as a functional disorder, where the body exhibits symptoms even without any physical problems. Meanwhile, IBD is what is referred to as a structural disease, which means tests are able to reflect visible causes (ulcers, inflammation) for the cause of pain. 

Inflammatory bowel disease is a chronic inflammation of the digestive tract. The two specific types of IBD are known as Crohn’s disease (inflammation of the digestive tract) and ulcerative colitis (inflammation of the colon lining and rectum with the possible appearance of ulcers).

The Difference Between IBS and IBD

Irritable Bowel Syndrome (IBS)Inflammatory Bowel Disease (IBD)
Symptoms– Nausea
– Gas
– Constipation
– Belly pain that is relieved with bowel movement
– Diarrhea
– Mucus secretion, which may also be present in stools
– Nausea
– Gas
– Constipation
– Belly pain
– Diarrhea
– Change in appetite
– Fever accompanied by irregular bowel movements
– Black tarry stools, usually accompanied by blood
– Inflammation 
Treatment  Mainly managed through dietary and lifestyle changes. Anti-inflammatory drugs to help with inflammation such as corticosteroids and aminosalicylates
DiagnosisDoes not produce visible symptoms. Leads to the development of ulcers along the stomach and colon lining. Characterized as the inflammation of the intestines. 

Can IBS Lead to Colon Cancer? 

Although IBS and colon cancer produce the same symptoms, the two are incredibly different conditions concerning the gastrointestinal system. Similar symptoms include:

  • Constipation 
  • Frequent and often urgent bowel movements
  • Needing to go to the bathroom even after bowel movement 

These symptoms are where the resemblance ends. Colon cancer occurs when growths called polyps grow in the colon lining and attach to nearby organs and lymph nodes. Colon cancer also produces a host of other symptoms that aren’t existent in IBS such as unprecedented weight loss, rectal bleeding, and vomiting. 

Patients suffering from IBS may also experience rectal bleeding that is likely caused by hemorrhoids that have formed due to overexertion. Unlike in colon cancer, the presence of blood in the stool may be caused by a wound near the anus, not high up in the colon from a bleeding polyp.

Read more: Your Blood Can Tell If You Have Colon Cancer

Irritable bowel syndrome is a disorder that prevents normal digestive functions. On the other hand, colon cancer is preceded by abnormal rates of polyp growth, which cannot develop from IBS alone. 

Types of IBS

types of IBS

There are three known types of irritable bowel syndrome. These three classifications describe the predominant symptom associated with a patient’s type of IBS. 

  1. IBS-C: Irritable bowel syndrome with constipation. Patients suffering from IBS-C experience frequent abdominal pain and bloating. Bowel movements are usually delayed, infrequent, and uncomfortable. Stool is often described as lumpy and hard. Drinking more water is a common suggestion for patients experiencing IBS-C.
  2. IBS-D: Irritable bowel syndrome with diarrhea. Patients experiencing IBS-D have frequent bowel movements, often watery in consistency. Abdominal discomfort due to the colon drawing in too much water is also present. Patients with IBS-D have overactive digestive systems that process food too quickly. A diet rich in soluble fiber (oats, legumes, sweet potatoes) are recommended to help manage diarrhea. 
  3. IBS-C and D: The predominance of constipation and diarrhea may be present in a patient. In this case, symptoms may overlap or alternate, and can be triggered depending on dietary and lifestyle choices. 

Irritable Bowel Syndrome: What Causes It? 

IBS causes

IBS is a condition diagnosed through exclusion, which means other conditions are ruled out before identifying IBS as the source of discomfort. Gastroenterologists also carefully study details and patterns  of the symptoms in order to rule out IBS. 

While the exact cause of IBS is unknown, there are several factors that are believed to contribute to the development of irritable bowel syndrome. These include:

Bacterial Infection

Post-infectious IBS can occur after a patient develops conditions like gastroenteritis or acid reflux. When the bacteria in the digestive tract takes over, bacterial infection can affect digestive function and lead to IBS. Around 10% of individuals who experience bacteria-induced gastroenteritis develop IBS afterwards. 

Changes In Gut Bacteria

Bacteria is present in the gut and can be beneficial in keeping “bad” bacteria away while also aiding in digestion. Changes in gut flora may prevent the digestive tract from operating normally.

Muscle Contractions

The intestine is lined with muscles that contract as food travels through the digestive tract. Muscle contractions can affect how the digestive system operates.

Longer muscle contractions can pull in more gas into the colon, leading to gas and bloating. Slower, weaker muscle contractions lead to slower food passage, resulting in lumpy stools and constipation. Similarly, fast muscle contractions often mean that more water is being pulled in the colon, which leads to fast digestion and loose, watery stools. 

Consistent deviation from normal muscle contractions can permanently disrupt the digestive cycle. When this happens, discomfort during digestion may be exacerbated, leading to IBS. 

Complications With Nervous System

Normal digestive signals may be misinterpreted by the brain, causing the system to overreact. When this happens, normal digestive functions may result in extra pain, diarrhea, and constipation. These abnormal reactions can become permanent, resulting in irritable bowel syndrome.  

Can Food Cause IBS?

IBS and food

No, there are no studies that support the direct link of food and IBS. On the other hand. contaminated foods and drinks may carry bacteria that could result in IBS symptoms. 

In reality, irritable bowel syndrome symptoms can only be triggered by food, not caused by it. Depending on the type of IBS experienced by the patient, certain foods may worsen episodes of diarrhea, constipation, or both. 

In general, these are the foods patients with IBS should aim to avoid:

  • Gluten: Gluten is a protein present in common grains such as wheat and rye. Some people are allergic to gluten and may experience diarrhea upon digestion. There is also a form of gluten intolerance that doesn’t involve an immune response to the protein. This intolerance still produces the same reactions of a gluten allergy, including persistent abdominal pain. 
  • Fiber: Adjusting fiber intake should be dependent on the type of IBS experienced by the patient. Insoluble fiber coming from vegetables and whole grains may worsen constipation. On the other hand, soluble fiber sourced from fruits and legumes may worsen diarrhea. 
  • Caffeine: Coffee, energy drinks, and certain tea products containing high levels of caffeine may prove too stimulating for the digestive system. When ingested in large amounts, caffeine can trigger diarrhea in patients with IBS. 
  • Dairy: Lactose intolerance is common among patients with IBS. Foods that have a high-fat content also tend to trigger constipation and diarrhea. Look for nonfat or low-fat alternatives to mitigate symptoms of IBS.    
  • Processed Food: Fried foods contain an increased amount of oil, sugar, salt, and other preservatives that could aggravate IBS symptoms. Watch out for foods that are labeled sugar-free; these synthetic sweeteners contain ingredients that are difficult to digest, which will only force your digestive system to work harder, resulting in abdominal pain. 

Can Stress Cause IBS?

woman under stress

A study published in the World Journal of Gastroenterology suggests that psychological stress may also inhibit normal digestive functions. Researchers believe that psychological stress affect intestinal sensitivity, altering immune responses and mucus secretion, both of which are crucial factors in safeguarding the intestine from bacteria. 

Although a direct correlation between stress and IBS has yet to be founded, recent findings point towards abnormal functions in the central nervous system as the main cause for this syndrome. Overstimulation of the system can affect brain-gut interactions, which ultimately changes the way the gastrointestinal system reacts to different stimuli.

Researchers also established a strong relation between the IBS severity and psychiatric disorders. They found that stressful episodes tend to coincide with IBS flare-ups in affected patients.

Further study is required to pinpoint stress as the primary source of IBS. Given its strong relations, psychological help is often administered to patients with IBS to help manage the symptoms. 

Tell-Tale Signs and Symptoms

tell tale signs of IBS

1. Abdominal Pain 

It’s normal for muscles to contract during digestion, but signal interruptions between the brain and intestine can exacerbate this sensation, leading to pain. Patients suffering from IBS have impaired brain-gut connection, leading to abnormal levels of abdominal pain and cramping. This pain is usually situated on the lower abdomen and can be relieved by a bowel movement. 

2. Diarrhea

Diarrhea is one of the predominant types of IBS, but can easily occur in patients with other types of IBS. For patients with irritable bowel syndrome, abnormal muscle contractions can promote faster bowel movement, leading to more frequent and urgent bowel movements. 

Some patients report having bowel movements twice the normal amount, and is typically accompanied by watery stools. Mucus secretion can happen to patients with IBS, which could also be present in the stools. 

Anti-diarrhea medicine can be used to prevent sudden bouts of diarrhea, but is usually not recommended for long-term use. Instead, lifestyle and dietary alterations are prioritized so patients can experience long-term improvements. 

3. Constipation and Indigestion

Constipation is another predominant symptom in IBS. In fact, 50% of IBS cases are considered constipation-dominant. Constipated patients find themselves on the other side of the spectrum; instead of fast-moving, watery stools, affected individuals report slower and fewer bowel movements that are often dry and lumpy.

While rare, the presence of blood in the stool may be caused by a hemorrhoid or an anal fissure from straining during the movement. Patients report having 1-3 bowel movements a week with IBS-C. Laxatives and increased water intake are prescribed to patients experiencing constipation.   

4. Bloating and Gassiness

Bloating is a common symptom for both IBS-C and IBS-D type syndromes. Many patients recognize bloating and gassiness as two of the most pervasive symptoms of IBS. A gas flare-up from IBS may last for 2-4 days but can easily be prevented with a conscientious approach towards food. 

Eating smaller meals more frequently, exercise, and a considerable reduction in fiber consumption are the key approaches to mitigating gassiness for IBS patients. 

5. Sensitivity to Food

Symptoms for food intolerance and food allergies can be quite similar, leading to the common assumption that IBS and food allergies are the same. The difference between food intolerance and food allergy is defined by immune response. In food allergies, the body responds to certain food proteins by activating antibodies called Immunoglobulin E (IgE) that “fight” that protein. 

On the other hand, the discomfort felt from food intolerance isn’t derived from an immune response. Sensitivity to certain food components (lactose in dairy products, for example) result from decreased levels or a lack of enzymes and digestive properties that allow the body to properly break down certain foods. 

Food intolerance often results in diarrhea. Food allergy, on the other hand, can lead to anaphylaxis — an immune response characterized by loss of consciousness and difficulty in breathing just by merely touching a specific type of food. 

6. Fatigue

Patients suffering from IBS often cite insomnia and fatigue as a side-effect of IBS. In a study involving 160 individuals with IBS, patients reported a decrease in stamina and generalized anxiety as non-intestinal side effects of IBS. Poor sleep quality and stress are perceived as the common reasons for fatigue in IBS patients.

When to See a Doctor

Symptoms for IBS remain the same and only fluctuate in severity and frequency over time. Experiencing the following symptoms may be signs of a worsening case of IBS or the development of other gastrointestinal complications: 

  • Undescribed, disruptive pain. Persistent or worsening pain that prevents you from continuing daily activities is a red flag and requires immediate medical intervention. 
  • Weight loss. Even IBS-D patients don’t experience rapid rates of weight loss. Get in touch with your physician when you start experiencing unexplainable weight loss alongside noticeable changes in appetite. 
  • Rectal bleeding. The presence of blood in the stool is uncommon in IBS cases. Fecal bleeding may point to more serious problems concerning the gastrointestinal system, which requires further study from your physician. 

5 Myths About Irritable Bowel Syndrome

myths about IBS

Incorrect assumptions regarding irritable bowel syndrome are prolific. For instance, IBD and IBS are commonly interchanged, while others believe that IBS is a rare and viral condition. 

Understanding the science behind irritable bowel syndrome helps with the taboo, considering this is a common disorder that affects millions of Americans, accounting for up to 3.5 million physician visits in the United States alone.  

Below are the top myths about irritable bowel syndrome, and the truths behind them: 

1. IBS leads to other diseases

There is an ongoing and incorrect understanding that IBS is a precursor to a host of gastrointestinal diseases such as IBD, colitis, and colon cancer. In reality, IBS is a separate condition that does not evolve into any of the aforementioned conditions. 

These disorders are preceded by different circumstances (in the case of colitis, the intestine is often infected with bacteria, leading to inflammation) that are not related to irritable bowel syndrome. 

2. IBS is a rare condition

According to the IBS organization, more than 40 million are affected by IBS in the United States alone. An estimated of up to 15% of the world population is affected by IBS. Women are likelier to develop IBS in men, accounting for 2 out of 3 cases of existing IBS cases. 

3. IBS is a chronic condition with no possible treatments 

Although irritable bowel syndrome is a long-term condition, there are treatment options available for patients who want to keep their symptoms under control. Medication and dietary restrictions are applied to patients depending on their type of IBS. 

For example, antispasmodics are recommended to patients who experience prolonged episodes of abdominal pain and constipation. It’s possible to improve a sufferer’s quality of life just with lifestyle changes alone. 

4. IBS symptoms are limited to the intestine

The presence of IBS can dampen a person’s quality of life, affecting factors that don’t involve digestive functions. As mentioned, a link between poor quality of sleep and IBS have already been suggested by researchers. 

Patients also report loss of appetite and generalized anxiety as a result of the syndrome. This is why psychological help is often recommended to patients to help them adjust to a life of living with the syndrome. 

5. IBS is impossible to diagnose

Unlike other gastrointestinal complications, IBS doesn’t produce physical alterations that can lead to a definitive diagnosis. Instead, gastroenterologists diagnose IBS by eliminating other possible disorders that could potentially be the source of discomfort. 

This doesn’t mean that the basis of the diagnosis is unscientific. The Rome Criteria, a criteria passed by a group of gastroenterologists at a conference in Rome in 1988, is being used to reach an accurate diagnosis for IBS. A revision, known as Rome IV, was released in 2016. 

The Rome Criteria pertains to “Recurrent abdominal pain, on average, at least 1 day per week in the last 3 months.” This description is used to observe and categorize the three most telling symptoms of IBS:

  • Patterns of defecations
  • Changes in frequency and consistency of bowel movements
  • Changes in appearance of bowels 

Diagnosing IBS 


40% of referrals to gastroenterologists are due to functional gastrointestinal disorders, and 12% of which are believed to be IBS cases.  Physical tests are commonly prescribed to the patient in order to rule out other complications. Understanding patterns and problems in key symptoms are also key in diagnosing IBS. 

The primary key in distinguishing IBS is abdominal pain located below the chest and above the hips. Pain that changes according to bowel habits is considered a hallmark in IBS diagnosis. 

The Rome Criteria is used to reach a definitive diagnosis only when there is no apparent intestinal abnormality. In other words, the Rome Criteria is only relevant when there are no known physical and biochemical abnormalities in the gastrointestinal tract. 

Patients also have to be experiencing the symptoms at least 6 months prior to the diagnosis and is persistent within the last 3 months to be distinguished as IBS.

Living with Irritable Bowel Syndrome: How to Manage It

IBS management

Various steps are taken in order to mitigate IBS symptoms. These lifestyle changes are known to improve a patient’s overall comfort and quality of life:

Reduce Stress: It’s not unusual for physicians to recommend psychological help alongside dietary modifications. Stress could aggravate IBS symptoms, and knowing how to manage day-to-day anxiety and stress can help prevent flare-ups. Relaxation and mindfulness techniques are taught to the patient in order to help the patient regain control and confidence even with IBS. 

Regular Exercise: Although it may seem counterintuitive to exercise with IBS, some studies suggest that a moderate 20 to 30-minute exercise improve symptoms in patients with irritable bowel syndrome. Patients who underwent a more active physical activity program showed less symptom severity than the group that didn’t have exercise in their routine. 

Modified Diet: The patient’s type of IBS will inform his or her dietary restrictions. Certain foods are known to trigger adverse reactions in an already irritable intestine. As a result, symptoms are less severe and reactionary, and can even disappear for longer periods of time before resurfacing again. 

Beat IBS With Gastro Center NJ

Not sure if you have IBS? Get in touch with us to reach a proper diagnosis today. At Gastro Center NJ, we employ a rigorous medical approach together with comprehensive customer care in order to give you the best level of professional help.

Book an appointment with us and learn how to manage your IBS symptoms so you can live your best life yet.