What is Irritable Bowel Syndrome?

Irritable Bowel Syndrome (IBS) is a disorder that affects the muscles and nerves of the bowel.  It is the most common, yet least understood functional gastrointestinal disorder, affecting one in five people in Australia.  IBS isn’t a disease itself, the diagnosis is often a process of ruling out other conditions.  It is important to speak with your GP about your symptoms before you begin any self-investigation. ​
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Signs and symptoms

The signs and symptoms of IBS can vary widely from person to person and often resemble those of other diseases – therefore it’s very important to speak with your doctor as soon as possible and have appropriate testing (including for Coeliac disease).
Note: Symptoms that indicate a more serious condition include rectal bleeding, weight loss and/or abdominal pain that progresses or lasts at night.

Symptoms can vary in severity and come and go, lasting for hours, days, weeks or months. For most people, IBS is a chronic condition, but for others it can improve or even disappear completely.

Some of the more common IBS symptoms include:
  • Abdominal pain or cramping – often relieved by passing wind or bowel motion
  • Altered bowel motions such as diarrhoea or constipation (or alternating between both)
  • A feeling of incomplete emptying of the bowel or sudden urgency
  • Mucus in the bowel motion
  • A feeling of fullness, or bloating of the abdomen (wind)
  • Reflux and / or feeling of poor digestion in the stomach
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Common causes

IBS can occur at any age. For many people with IBS, the bowel appears to be over-sensitive. Unfortunately the cause isn’t always known, but a variety of factors can play a role:​
  • Foods: The role of food intolerance in IBS isn’t clearly understood, but many people have symptoms after eating certain foods. For some people too much fibre, fat or spices for example can be the culprit, but for others it can be trickier to identify. Removing certain foods for a period of time as guided by your Dietitian can be an effective way to get you feeling better quickly.  You can then experiment with food challenges to see which are problematic for you. Depending on symptoms, research shows that four out of five people with IBS will improve on the Low FODMAPs diet (click to read more about this). Otherwise, refer to my page on food intolerances for details on other commonly problematic foods.​
Regardless of which foods cause your IBS symptoms, often just simply removing them doesn't address any underlying issue. It's important we consider suitable treatments or therapy that can help to restore optimal gut function and health. Read more about my approach to IBS
  • ​Hydrochloric Acid and / or Pancreatic Enzyme deficiencies: Some people are born with, or develop, insufficient enzymes to digest some foods. For example, a deficiency of the enzyme lactase results in lactose intolerance. Insufficient stomach acid production will also cause digestive issues. Chronic stress can cause a decreased output of digestive acid and enzymes. Digestive support supplements may be suitable for you in the short-term. Learning from your Dietitian how to support your digestion will be important for long-term management.   ​  
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  • Post-infection: Up to 30% of people after acute infectious gastroenteritis present with prolonged gastrointestinal symptoms and can meet the diagnostic criteria for post-infectious irritable bowel syndrome. Other infections that can cause gut issues include parasites, yeast overgrowth and overgrowth of bacteria in the small intestine (SIBO). Your Doctor and Dietitian can help you investigate these through stool and breath testing and / or get you started on a treatment plan.  
 
  • Antibiotic use: While antibiotics are helpful at treating bacterial infections, they also kill good bacteria in the gut. This disruption of gut flora, particularly in the colon, can create an environment for opportunistic bacteria and pathogens to thrive and result in dysbiosis (an imbalance of the types of organisms e.g. bacteria, yeast such as candida). This is a common cause of IBS. 
 
  • Stress and anxiety: Most people with IBS find that their symptoms worsen or are more frequent at times of increased stress or anxiety.  This may be due to a number of reasons. Research suggests that stress changes gut microbiota community structure and activity. Some studies have linked gut microbes and their metabolites with gut inflammation, 'leaky gut' / permeability, gut symptoms and psychological attributes. Stress can also alter motility and reduce digestive ability for reasons including redirection of blood and oxygen away from the digestive tract and also altering the signalling of major nerves in the gut. Stress can also impair the immune system, directly altering gut microbiota composition and function. Stressors can include psychological (anxiety, cognitive demands, fear etc.), physical (strenuous exercise, sleep deprivation,  undernutrition etc.) and environmental (high altitude, climatic extremes, pollutants, toxicants, pathogens etc.).
 
  • Hormones: Because women are twice as likely to have IBS, researchers believe that hormonal changes play a role in this condition. Many women find that signs and symptoms are worse during or around their menstrual periods.  This can be resolved with specific dietary and lifestyle changes. 
 
  • Medications: Some medications (e.g. antibiotic, antacids, painkillers) and supplements (e.g. iron) can cause gut irritations and lead to constipation or diarrhoea.  Long-term use of anti-reflux medications have also been linked to digestive issues and gut infections like Small Intestinal Bacterial Overgrowth (SIBO).    

Don't forget to read about
how I can help you ​​with your IBS...