Understanding IBS: A Guide to Managing Symptoms and Triggers
What Exactly Is IBS?
Irritable bowel syndrome (IBS) is one of the most common gastrointestinal (GI) disorders in developed countries, affecting 10-25% of the population.1 Despite its prevalence, IBS can be challenging to define as there’s no definitive test to diagnose it. Instead, IBS is diagnosed by ruling out other conditions like coeliac disease, infections, or inflammatory bowel disease (IBD).2
IBS is characterised by chronic abdominal pain or discomfort, often accompanied by changes in bowel habits.3 These can range from diarrhoea to constipation or a combination of both. For a diagnosis of IBS, symptoms must have been present for the last three months, with the onset of symptoms occurring at least six months before.4
Though it primarily affects the gut, IBS is now recognised as a disorder of the gut-brain axis, due to the strong link between digestive symptoms and mental health issues like anxiety and depression.5
Who Is Most Likely to Get IBS?
IBS affects all age groups but is most commonly diagnosed in women, who are 1.5 to 3 times more likely to develop the condition than men. Symptoms often appear before the age of 35, with half of IBS sufferers reporting that their symptoms began in early adulthood.6,7 While IBS is generally considered a lifelong condition, there is a 25% lower incidence in people over 50.8 There also appears to be a genetic link, with those who have a first-degree relative with IBS being twice as likely to develop it themselves.9
What Are the Key Symptoms of IBS – Is It the Same for Everyone?
IBS presents differently in everyone, making it a complex condition. The hallmark symptoms are chronic abdominal pain, discomfort, and changes in bowel habits, including diarrhoea, constipation, or a combination of both.3 Additional symptoms often include bloating, flatulence, abdominal distension, and an urgent need to use the toilet.
Given that IBS is now classified as a gut-brain disorder, it’s common for sufferers to experience mood-related symptoms such as anxiety and depression.10 Many people with IBS also report fatigue, likely due to impaired digestive function, which can affect nutrient absorption and overall energy levels.
What Causes IBS – Is It Something You're Born With, or Do You Develop It Over Time?
IBS is considered a multifactorial condition, meaning that several factors contribute to its development. While some people may be genetically predisposed to IBS, environmental factors like diet, lifestyle, stress, and gut inflammation also play significant roles in triggering symptoms.
Predisposing factors include genetic links, immune system dysregulation, nervous system imbalances, and hormonal fluctuations.11 These factors can interact with external triggers like food sensitivities, infections, toxins, or adverse life events. One key area of interest in IBS research is the role of gut microbiota imbalance. A growing body of evidence now supports the idea that an unhealthy balance of gut bacteria can contribute to IBS.12
Is IBS Genetic?
There is evidence to suggest a genetic component to IBS, although research in this area is still evolving. Recent studies, including a large survey from Sweden involving over 50,000 participants, have shown that first-, second-, and third-degree relatives of IBS sufferers are at a higher risk of developing the condition, confirming a genetic link.13 However, while genetics may play a role, the development of IBS is likely influenced by a combination of factors, including environmental triggers and lifestyle.
What Are the Most Common Dietary Triggers for IBS?
Certain foods can aggravate IBS symptoms, with many sufferers being sensitive to FODMAPs (Fermentable Oligo-, Di-, Mono-saccharides, And Polyols). FODMAP-rich foods include certain vegetables (like onions and garlic), fruits (especially stone fruits), beans, and lentils. Gluten and dairy are also common triggers.
Processed foods, which are loaded with hidden sugars, sweeteners, additives, and emulsifiers, can negatively impact gut bacteria, leading to inflammation and worsening IBS symptoms.14 Many people experience rapid improvements by cutting out processed foods and adopting a wholefoods diet.
To identify dietary triggers, it may be necessary to follow an elimination diet, where common culprits like FODMAPs, gluten, dairy, and caffeine are removed and then gradually reintroduced. However, it’s crucial to work with a registered Nutritional Therapist to avoid nutrient deficiencies during this process. Eliminating irritating foods can also create a window for gut healing, helping to reduce symptoms over time.
It’s important to consider not just what you’re eating, but also how you eat. Digestion starts in the brain—the anticipation of food triggers the release of stomach acid, enzymes, and bile, all of which help break down food. If these digestive processes are impaired, food may ferment in the gut, causing gas, bloating, and other uncomfortable symptoms. Eating mindfully—taking time to relax, chew thoroughly, and avoid distractions—can go a long way in improving digestion.
What About Emotional Triggers?
Stress and anxiety are common triggers for IBS. Many sufferers link their symptoms to emotional stress, whether it’s the initial cause of their condition or a factor that exacerbates their symptoms. The digestive system is highly sensitive to stress, and when we're stressed, we produce less stomach acid and fewer digestive enzymes. Stress can also negatively impact gut bacteria, increasing the risk of bloating and gas.
Research increasingly suggests that IBS is not just a condition of the bowel, but also of the brain, with the two intricately linked via the gut-brain axis. This explains why therapies aimed at reducing stress, such as cognitive behavioural therapy (CBT) and meditation, have shown significant benefits for IBS sufferers. These approaches help to manage the psychological aspects of the condition and, in turn, reduce physical symptoms.
Conclusion
IBS is a complex and multifactorial condition that affects both the digestive system and mental health. While genetic factors may predispose individuals to IBS, environmental and lifestyle triggers, such as diet, stress, and gut bacteria imbalances, play a significant role in its development and symptom management.
Through a combination of dietary changes, stress management, and, in some cases, probiotic supplementation, it’s possible to improve IBS symptoms and enhance quality of life. However, as every individual’s experience with IBS is unique, personalised approaches to treatment, with the support of a healthcare professional, are essential.
References
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