Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder, also referred to as a disorder of gut-brain interaction. This means IBS affects how the gut and brain communicate and how the gastrointestinal tract functions, but does not cause inflammation nor does it affect the structure of the gastrointestinal tract. Those with IBS tend to experience increased “visceral sensitivity,” meaning nerves in the digestive tract are particularly sensitive.
While you must be evaluated by a physician to receive an official IBS diagnosis, typically the Rome IV Diagnostic Criteria for IBS is used by gastroenterologists as standard practice. To meet these diagnostic criteria, you must experience two or more of the following symptoms, associated with recurrent abdominal pain one or more days per week, in the last three months on average:
Additional symptoms such as bloating and excessive gas are also common in those with IBS.
There are three subtypes of IBS:
While the cause of IBS is not fully understood, a number of factors are thought to play a role in IBS onset and exacerbation including but not limited to: abnormalities in nerve signaling between the gut and brain, overgrowth of bacteria in the small intestine (also referred to as “SIBO”), and psychological stress. IBS may also develop after an individual contracts a severe gastrointestinal infection, suggesting that our gut microbiome may play a role, too.
Although they have similar names, IBS should not be confused with inflammatory bowel disease (IBD). While IBD can affect the function of the gastrointestinal tract and may have some overlapping symptoms with IBS, IBD is not a functional gastrointestinal disorder. Rather, it is an autoimmune disease that causes physical damage to the gastrointestinal tract through ulceration and inflammation. The two most common phenotypes of IBD are Crohn’s disease and ulcerative colitis. While IBD and IBS are unrelated, it is possible for an individual to have both IBD and IBS concurrently.
If you experience unintentional weight loss, blood in your stool, fever, vomiting, diarrhea at night, changes in appetite, unexplained iron deficiency anemia or other nutrient deficiencies, or a sudden onset of symptoms, you should seek care from a gastroenterologist as soon as possible to be evaluated. These symptoms may be indicative of IBD or other conditions requiring medical intervention.
If you suspect you may have IBS, it is helpful to first reflect back on when your symptoms began. Did your symptoms begin suddenly, or have you had these symptoms for a while? If your symptoms began recently, are there any recent dietary or lifestyle changes that they may be attributed to? For example, have you been experiencing increased stress, poor sleep quality, or consuming more caffeine than usual? Did you make any dietary changes around the time your symptoms began? Any of these factors may trigger or worsen gastrointestinal symptoms. Keeping a food and symptom journal for a few days may help you identify patterns and attribute your symptoms to specific foods or other dietary factors. It can also be helpful to note your stress level and mood, sleep quality, and physical activity in your food and symptom journal, to see if non-dietary factors may be at play.
If your symptoms persist after you have addressed these factors, or if you are experiencing any of the symptoms outlined above that may warrant medical intervention, then it is best to see a gastroenterologist to be evaluated. Aside from IBS symptoms overlapping with some symptoms associated with IBD, IBS symptoms may also overlap with those of many other conditions such as Celiac disease, small intestinal bacterial overgrowth (SIBO), colorectal cancer, diverticulitis, and infection. Therefore, it is important to rule out other potential explanations for your symptoms first. Additionally, if you have a family history of IBD, Celiac disease, or colorectal cancer, you should be evaluated by a gastroenterologist sooner rather than later, as you may be at increased risk for developing these conditions.
A gastroenterologist will review your symptoms and medical history, may perform a physical exam, and taking this information into account, may order different diagnostic tests if warranted, such as:
If you were recently diagnosed with IBS, it’s helpful to work with a registered dietitian who specializes in IBS. A registered dietitian will help you identify potential food triggers and implement dietary and lifestyle strategies to aid in symptom management. A specialized registered dietitian will also be able to determine whether or not you are an appropriate candidate for the low FODMAP diet.
The low FODMAP diet is an elimination diet for IBS. FODMAP stands for “fermentable oligosaccharides, disaccharides, monosaccharides, and polyols” which are names for different types of carbohydrates. These carbohydrates can cause gut symptoms for some individuals with IBS.
FODMAPs are eliminated for a few weeks and then systematically reintroduced, to determine an individual’s tolerance to different FODMAPs. Eventually, FODMAPs that the individual tolerated are reincorporated into their diet, and FODMAPs that triggered symptoms will either be avoided entirely or limited depending on the individual’s tolerance threshold. The Fig app is a great tool for starting a complicated elimination diet like the Low FODMAP diet.
Even after an individual enters the “maintenance phase” of the low FODMAP diet, it is beneficial to periodically re-test foods they did not tolerate, to see if they can eventually reincorporate small quantities back into their diet. Since our gut microbiome is constantly shifting and evolving, it is possible for someone to eventually tolerate small quantities of a FODMAP that previously triggered their IBS symptoms.
It is important to note that the low FODMAP diet is not intended to be a long-term diet and following it for a prolonged period without supervision from a registered dietitian can lead to nutritional deficiencies and impair gut microbiome health. It is therefore recommended to work with a registered dietitian to guide you.
Your gastroenterologist may be able to refer you to a dietitian in your area, or you can go to the “Find a Nutrition Expert” page of the Academy of Nutrition and Dietetics website. There, you can find a registered dietitian practicing in your area, and can add a search filter for dietitians specializing in GI disorders.
In the meantime, keeping a food and symptom journal is helpful, and sharing this with your dietitian will allow you to get more out of your initial session. Even if you are unable to work with a registered dietitian, a food and symptom journal can help you identify factors that worsen your symptoms. Aside from considering specific food triggers, it is also helpful to notice your overall fiber intake. Are you consuming plenty of fruits, vegetables, whole grains, nuts, and seeds throughout the day? If not, your fiber intake may be falling short, contributing to worsened symptoms. If you eat plenty of fiber-rich foods, perhaps you would benefit from increasing the ratio of soluble fiber to insoluble fiber in your diet. Soluble fiber is generally best tolerated and helps regulate bowel function. It’s found in the fleshy parts of fruits and vegetables such as bananas, oranges, kiwi, carrots, and winter squash, as well as in foods like chia seeds and oats. Insoluble fiber on the other hand, is often referred to as “roughage,” and is found in the skins of fruits and vegetables, the outer portion of beans and legumes and nuts and seeds, and in bran and bran products.
Eating large portions of fat within one sitting, consuming excessive amounts of caffeine or drinking coffee on an empty stomach, consuming sugar alcohols, spicy foods, alcohol, and lactose are all common IBS symptom triggers to consider when reviewing your food and symptom journal, to assess your tolerance and see if you might benefit from limiting or eliminating some of these foods, beverages, or behaviors.
In addition to food, consider your water intake and physical activity level. Are you drinking plenty of water throughout the day and moving your body regularly? Staying well-hydrated and engaging in regular physical activity promotes regularity. Physical activity can also help relieve stress and promote better sleep quality, both of which may also improve GI symptoms. Speaking of sleep quality, do you typically have trouble falling asleep or staying asleep? Consider implementing a bedtime routine and limiting screen time before bed, to relax you and set you up for a restful night’s sleep. This may include things like reading a good book before bed, taking a bath, practicing a guided meditation, or listening to calming music.
How we eat can be just as important as what we eat. Do you typically eat very quickly or while standing up, stressed, or distracted? When we eat in a stressed state, our body goes into “fight or flight” mode, diverting blood away from our digestive organs, and towards our arms and legs. This impairs digestion, and may lead to worsened IBS symptoms. Although easier said than done, try to reserve at least 20 minutes for each meal without outside distractions such as scrolling on your phone, checking emails, or watching TV. For optimal digestion, focus on the flavors, aromas, and textures of your meal, sit down, and chew your food thoroughly.
Are you typically a grazer, snacking continuously throughout the day? Do you frequently skip meals or allow many hours between each eating occasion? Irregular meal patterns can worsen symptoms such as constipation, diarrhea, and abdominal bloating or distention. Aiming to space your meals approximately 3-4 hours apart during the day is a good ballpark for most individuals to aim for.
Some individuals who experience more severe or persistent IBS symptoms may benefit from certain medications to improve their quality of life. If you have tried implementing dietary and lifestyle strategies to manage your IBS, but still experience disruptive symptoms, you should speak with your gastroenterologist to see if medication is right for you.
Certain supplements such as soluble fiber supplements or magnesium supplements may also be beneficial depending on the individual and type of IBS. Before beginning a supplement, it’s important to speak with your healthcare team to make sure it is safe for you to do so. Your registered dietitian or gastroenterologist will be able to recommend specific brands and dosages that are appropriate for you.
If available to you, alternative therapeutic modalities may provide additional symptom relief. Alternative therapies commonly used for IBS management include pelvic floor physical therapy and gut-directed hypnotherapy. Since pelvic floor dysfunction is sometimes associated with IBS-C, working with a pelvic floor physical therapist can be particularly helpful to strengthen and re-train the pelvic floor muscles, promoting regularity.
Gut-directed hypnotherapy is an emerging treatment approach to IBS that involves a combination of guided imagery, relaxation techniques, and hypnosis to help improve GI motility and reduce sensitivity. In fact, some research suggests that gut-directed hypnotherapy can improve GI symptoms in those with IBS by 70-80%. To find a healthcare practitioner specialized in psychogastroenterology who may provide gut-directed hypnotherapy near you, you can go to the Rome Foundation website and type in your zip code under the “GastroPsych Directory” page.
If you suspect you may have IBS, there are a number of factors to take into consideration and it’s important to be evaluated by a physician to rule out conditions that may mimic IBS symptoms. While navigating an IBS diagnosis can be challenging, remember that you are certainly not alone. In fact, an estimated 25 to 45 million Americans are living with IBS. Through a combination of dietary and lifestyle adjustments as well as medication, supplementation, or alternative therapies if warranted, it is possible to achieve symptom control and a significantly improved quality of life. Remember, the Fig app is always here to help you find the foods that help you feel your best!