Irritable bowel syndrome (IBS) (EER-ih-tuh-bul BOW-ul SIN-drome) is a chronic bowel condition affecting the digestive system, which is characterised by a group of symptoms commonly consisting of abdominal pain, constipation, bloating, cramping pain, and diarrhoea. It has been estimated that 13 million people in the UK suffer from IBS, which impacts their daily routines, such as missing school or work, and causes a healthcare burden as the most commonly diagnosed gastrointestinal disease.¹ 

IBS should not be confused with inflammatory bowel disease (IBD). Whilst both distinctive illnesses have similar irritative symptoms, including diarrhoea and stomach aches, IBD is far more severe by causing inflammation to the digestive tract - this is the body’s defence response against pathogens and bacteria. The inflammation produced can damage the intestines, which therefore increases the risk of developing colon cancer. On the other hand, IBS does not damage the digestive system, nor does it raise any concerns of attaining debilitating diseases.²

Most people with IBS have mild to moderate symptoms, but a small percentage may have severe symptoms, alongside those that have been previously mentioned. This includes:³

• Nausea
• Bowel incontinence (unable to control bowel movements) 
• Being tired/lethargic
• Anxiety and depression
• Back pain
• Flatulence (excessive wind) 
• Heartburn
• Sweating 
• Stomach discomfort 

Secondary symptoms, in particular sweating and discomfort to the stomach, are not commonly well-known symptoms - yet many people do experience it. These symptoms frequently indicate physiological reactions that may worsen the underlying illness, such as hormonal changes brought on by stress, activation of the nervous system, or dietary changes. It is therefore important to be aware of these additional symptoms to ensure that a comprehensive diagnosis can be carried out by your doctors, in order to create an appropriate tailored treatment plan. 

Causes of stomach discomfort in IBS

Whilst IBS can start from any age and can affect anyone, women are 1.5–3.0 times more likely to suffer from IBS compared to men according to a survey, with a prevalence of 14% in women and 8.9% in males.⁴ In addition, IBS rates are significantly lower in people 50 years of age or older than in people under 50. The exact cause remains unclear despite the advancement of technology. Scientists speculate that there is a combination of factors that contribute to the development of this bowel disorder. 

Gut-brain axis

Have you ever experienced “butterflies” in the stomach? Perhaps, a strong “gut” feeling about a particular decision? All of these sensations originate from a communication system between your brain and your gastrointestinal tract (GI; referred to as your gut) known as the gut-brain axis. In other words, your brain health influences your gut, and vice versa. These organs are connected biochemically, physically, and even emotionally due to neurons. 

Neurons are brain cells that transmit signals throughout the rest of the body. Interestingly, there are over 200 to 600 million neurons lined in your gut, also referred to as the enteric nervous system (ENS), which is more than the number of neurons found in your spinal cord.⁵ From the lower portion of the oesophagus to the rectum, the ENS is a network of sensory neurons, motor neurons, and interneurons implanted in the gastrointestinal system wall. It connects the brain's emotional and cognitive centres with peripheral gut functions through both direct and indirect pathways, particularly through the vagus nerve. Like a cable connecting the heart, gastrointestinal system, and lungs to the brain, the vagus nerve provides a connection between these organs.

Linking back to our topic of interest, the vagus nerve normally senses and is triggered by gut microbes and metabolites that respond to diet, such as short-chain fatty acids (SCFAs), or by endocrine factors, enzymes, and neurotransmitters, including serotonin and dopamine to name a few.

This communication can become dysregulated in IBS. Its pathogenesis involves changing the gut microbial composition, decreasing the integrity of the intestinal mucosal, and causing low-grade inflammation. External factors, such as stress, can increase the severity of IBS symptoms by triggering the interlinked gut-brain axis. Similarly, gastrointestinal distress can affect mood and stress, resulting in a feedback loop that contributes to IBS symptoms.⁶

Food triggers

Food has been identified by many patients as a trigger for the onset of IBS symptoms. Research indicates that up to 84% of people with IBS experience symptoms connected to diet.⁷ Over 50% of individuals with IBS self-report food intolerances and symptoms that worsen with certain foods or are related to meals, usually within 3 hours of eating. IBS sufferers frequently try to change their diets on their own by cutting out foods they believe are contributing to their symptoms, which may result in inadequate nutrition or lower-quality diets. 

The most common items reported include:

• Dairy products such as milk, cheese, butter, and yoghurt
• Citrus fruits and banana
• Chocolate
• Coffee and tea 
• Onions, peas, and potatoes
• Wine
• Beans and lentils
• Cereals such as wheat, corn, oats, and barley
• Fried meals⁸

One item may affect an individual with IBS, however it may not affect another. You are the only one who knows what foods to avoid if you have IBS symptoms following consumption of the item. Therefore, unfortunately, there is not a single comprehensive list that works for everyone with IBS, or even the majority of them. 

Abnormal gastrointestinal motility

Abnormal gastrointestinal motility is a key factor in IBS. When the nerves or the muscles of the GI tract do not contract correctly, irregularities can arise, which causes overly rapid movement of the GI tract (this may result in a diarrhoea-predominant IBS (IBS-D)) or slow movement, which may cause constipation-predominant IBS (IBS-C). This may stem from a miscommunication in the gut-brain axis, changes in the gut microbiota or a heightened sensitivity of GI muscles. As a result, this results in an incomplete bowel movement, cramping, bloating, and discomfort to the stomach.⁹

The connection between IBS and excessive sweating

IBS-related sweating can be very severe and frequently appears suddenly. It's not just a little sweat, it might be so much that it causes discomfort and self-consciousness. You may experience an abrupt spike in body temperature, followed by a distinct feeling of perspiration, particularly on your back, underarms, and forehead.

The link between IBS and excessive sweating is rooted in the body's stress and discomfort response. IBS frequently causes the sympathetic nervous system, which controls the "fight or flight" response, to become activated. Excessive perspiration may result from this activation, particularly during flare-ups that are accompanied by discomfort or pain in the abdomen. This reaction is worsened by stress hormones like cortisol and adrenaline, leading to an increased production of sweat. Severe IBS symptoms, such as cramping or diarrhoea, can also cause a physical stress reaction, which increases sweating as the body tries to regulate temperature and maintain a balance within the body.¹⁰

Management and coping strategies

Although there is a lack of permanent solutions to dealing with IBS, there are strategies that you can implement to improve IBS symptoms, in particular sweating and discomfort. 

Dietary modifications

Changing your diet and habits can significantly reduce any flare-ups associated with IBS. 

• Hydration: ensure that you are drinking sufficient water throughout the day and that you reduce any caffeine intake
• Bring your lunch: pack your friendly “IBS-safe” meals for work or school, and avoid eating on the run
• Diary: keep a food diary of any food items that may be causing IBS symptoms to keep track. In this manner, you can avoid the item completely and swap it for an alternative to build a diet just for you. 
• Speak to your dietician: your doctor will be able to construct a diet plan in accordance with your intolerances and needs, which will help to ensure that you receive the right amount of nutrients
• Meal times: avoid delaying your meals, skipping these, and eating too quickly to allow your GI tract to work efficiently. You may wish to try smaller meals spread out across the day to help avoid major symptoms¹ 

Stress management

Whether we realise this or not, stress has a tremendous negative effect on the body. Incorporate strategies to reduce stress, such as yoga, meditation, tai-chi, or a hobby that you enjoy to relax.

Lifestyle changes

IBS can be stressful to manage on your own. You may find yourself often late to school, work, or other activities due to having frequent bowel movements or aches. Sometimes, you may even find yourself skipping these events. Some ways to manage include:^1,3  

• Telling someone: whether that is a teacher or your supervisor, informing a trusted or sympathetic individual can help you advocate for your needs and make any required adjustments
• Get up earlier: to ensure that you have the time to run quickly to the bathroom after having breakfast
• Carry an emergency kit: in case you have a potential IBS attack outdoors
• Speak to your doctor: consider speaking to your doctors to get prescriptions for laxatives, anti-cramping medicines, antidiarrheal medicines, and antibiotics

Summary

IBS is a bowel condition affecting the digestive system, leading to a group of symptoms which comprises bloating, constipation, diarrhoea, and abdominal pain. Secondary symptoms, such as discomfort and sweating, can be caused due to food triggers, alteration in the gut-brain axis, activation of the fight or flight, or abnormal gastrointestinal motility. There are several coping strategies that you can implement to avoid IBS symptoms, including making lifestyle changes, reducing stress, and changing your diet. If you feel seriously unwell, dial 111 and speak to a medical professional.