The Irritable Bowel Syndrome (IBS) Diet Guide

August 31, 2024

Irritable bowel syndrome (IBS) refers to a cluster of symptoms that affect the large intestine, including abdominal pain, bloating, diarrhea, constipation, and an increase in flatulence. Patients with IBS experience these symptoms regularly, and the symptoms occur without any signs of disease or visual damage to the digestive tract itself. Irritable bowel syndrome is especially common among women under fifty years old, and patients with mental health conditions such as anxiety or depression are also more likely to develop it.

To diagnose IBS, doctors perform a physical examination, and some patients may need to have a blood test for celiac disease. After ruling out other possible causes for the patient's symptoms, doctors may rely on the Rome or Manning criteria to diagnose this syndrome. Treatment options for IBS include dietary changes and the use of laxatives or fiber supplements. Anticholinergic medicines might be prescribed to reduce bowel spasms, and newer medicines such as linaclotide, alosetron, and eluxadoline have been specifically designed for irritable bowel syndrome treatment.

Most doctors recommend significant dietary alterations to help patients manage the symptoms of IBS. The dietary guidelines outlined below are among the most frequently recommended changes.

Cook All Vegetables

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Although vegetables are an important part of a healthy diet for patients with irritable bowel syndrome, doctors and nutritionists typically recommend these patients cook all the vegetables they eat. Anecdotal evidence suggests consuming raw vegetables could exacerbate IBS symptoms, resulting in more severe abdominal pain and an increase in bloating, constipation, and diarrhea. Raw foods are more difficult to digest, and some experts believe consuming raw vegetables may lead patients to naturally consume a larger volume of vegetables than they might eat if the vegetables were cooked.

Other researchers note some of the most popular vegetables used in raw salads, including mushrooms, snow peas, celery, and onions, are considered high-FODMAP (Fermentable Oligo-, Di-, Mono-saccharides, and Polyols) foods. These foods are poorly absorbed by the intestines, and they are recognized as triggers for irritable bowel syndrome symptoms. Regardless of the vegetables a patient chooses, cooking a vegetable will make it much easier for the body to digest. Patients might want to experiment with different cooked vegetables in their diets to see how they respond.

Consume Fruit Without Skins

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Fruit skins contain insoluble fiber, which does not dissolve in water and is difficult to digest, so it remains mostly intact as it passes through the digestive system. Insoluble fiber makes stools bulkier, and it enables waste to pass through the bowels quickly. Eating too much insoluble fiber could worsen symptoms of diarrhea, so IBS patients who have diarrhea as one of their symptoms are often advised to consume fruit without skins. Since vegetable skins also contain insoluble fiber, individuals struggling to manage their irritable bowel syndrome symptoms may want to peel all of their fruits and vegetables. Fruits such as bananas may be helpful for patients with IBS. Some patients have reported problems with digesting melons, citrus fruits, and apples.

Avoid Spicy Or Fried Food

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Generally, patients with irritable bowel syndrome will want to avoid spicy or fried food. Spicy foods frequently contain capsaicin, a substance that could burn or irritate the lining of the stomach or intestines. However, some spices, including ginger, turmeric, cumin, and coriander are considered safe for IBS patients. When dining out at a restaurant, it may be helpful to ask for a full list of ingredients so any problematic spices can be avoided. At home, patients may wish to experiment with different types and quantities of spices to discover which ones they can tolerate; keeping a food and symptom diary can be useful for this task. Doctors typically advise IBS patients to avoid fried foods, as these foods often have a high fat content, and this can make them very hard to digest when irritable bowel syndrome is present. Frying may even alter the chemical composition of some foods, making them even more difficult to digest. Experts suggest IBS patients opt for low-fat foods when possible, and baking or grilling can help ease digestion.

Increase Fiber Slowly

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Since fiber intake can be problematic for individuals with irritable bowel syndrome, it is helpful to increase fiber slowly. Studies indicate soluble fiber can reduce IBS symptoms for many patients. This type of fiber is found in oatmeal, beans, prunes, carrots, and peas. Although bran is another source of soluble fiber, it is known to exacerbate bloating for some patients, so doctors typically suggest alternative soluble fiber sources instead.

Current guidelines for healthy adults advise a daily intake of between twenty-two and thirty-four grams of fiber. To meet this requirement, doctors suggest IBS patients increase their intake by two to three grams per day; doing so may reduce the bloating and gas that could occur if fiber is consumed too quickly. In addition to fiber from food, some patients may benefit from taking a fiber supplement, though it is important to consult a physician before use. While increasing fiber intake, patients will also need to increase their water intake to help with symptom management. Eight to ten cups of water are recommended as a daily guideline for IBS patients.

Enjoy Chicken And Fish

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Irritable bowel syndrome patients often find they enjoy chicken and fish as part of their diet. These foods are comprised mostly of protein, which is easy for the body to digest, and since it does not ferment in the gut, it will not cause the patient to have gas. Experts suggest individuals with IBS choose white meat chicken instead of dark meat. White meat chicken is generally leaner than dark meat, and it does not contain the inflammation-causing fats that may be found in some dark meat. The high levels of omega-3 fatty acids in fish might help irritable bowel syndrome patients reduce the inflammation that contributes to their symptoms. To avoid potential toxins in fish, IBS patients are advised to choose wild-caught, organic fish instead of factory-raised fish. Salmon, mackerel, herring, white fish, and sardines are excellent sources of omega-3s.

Consider Avoiding Gluten

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Not everybody with irritable bowel syndrome has a gluten intolerance, but there is a larger prevalence of gluten intolerance in patients with this condition than in individuals without it. If individuals are not sure whether gluten affects them, they should try avoiding it for a few weeks and see if their symptoms improve. Gluten is found in whole grains like wheat, barley, and rye. This protein sometimes causes allergic reactions. If individuals are allergic to gluten, the condition is known as celiac disease. Celiac disease can sometimes present with symptoms similar to those of irritable bowel syndrome with diarrhea predominance. Celiac disease is classified as an autoimmune disorder because it occurs when the immune system attacks healthy tissues. This reaction happens when individuals eat gluten, and the disease can cause changes to intestinal cells over time. In turn, this leads to trouble absorbing nutrients and further intestinal distress.

Reduce Consumption Of Processed Food

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Pretty much everyone can benefit from reducing their consumption of processed foods, but irritable bowel syndrome patients can especially benefit. Not all processed foods are inherently bad. For a food to be processed, it just needs to have been handled in some way before reaching the consumer. But when health professionals talk about processed foods, they tend to mean foods that contain imbalanced nutrient levels and chemical preservatives. Added sugar, salt, and indigestible chemical content can all irritate the intestines and lead to irritable bowel syndrome flare-ups. The nutritional content doesn't always matter either. Sometimes the problem is that a highly processed food has been fried or otherwise had fat content added. Meals cooked at home from fresh ingredients tend to be an ideal alternative to processed food purchases. If individuals don't have the time or inclination to cook, it doesn't mean they're doomed. They just need to be more mindful of the ingredients and the nutrition facts on the packages of food they buy. They should look for ones with few long preservative names and high levels of essential daily vitamins.

Drink Lots Of Water

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It's easy to become dehydrated without realizing it, even if an individual doesn't have irritable bowel syndrome. These patients tend to need to consume more water than the average person. In the past, doctors believed drinking too much water would cause dilution of the digestive juices. But this isn't true at all, and this medical advice led many individuals to become chronically dehydrated for no reason. Nowadays, doctors recommend that an individual with irritable bowel syndrome drink between six and eight glasses of water daily. This should be plain water rather than flavored water or other beverages. Some research indicates sipping water slowly and intermittently during a meal can help food pass through the digestive system. If individuals don't drink enough water, they could make their irritable bowel syndrome symptoms worse, especially if they involve constipation. Lack of water can also lead to nausea, fatigue, and general feelings of unwellness even in individuals who don't have irritable bowel syndrome. If individuals have a flareup that causes a bout of diarrhea, it's also important for them to replenish the liquid they lose.

Reduce Use Of Oil In Cooking

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One important thing individuals with irritable bowel syndrome can do is to reduce the use of oil in cooking. Even if they're making all their meals at home by using fresh ingredients, they might still be triggering flareups by using high quantities of oil or fat. There are also substitutes individuals can use for different types of oil so they don't have to sacrifice the flavor of their meals entirely. If individuals use a lot of butter when they cook, experts recommend switching to olive oil. For every cup of butter in a recipe, individuals can use three-quarters of a cup of olive oil with a quarter cup of butter and get the same effect. However, if this fix leads to using too much olive oil, it can also lead to intestinal distress. Olive oil tends to wreak less havoc on the digestive tract than butter, but it's not always great to have in a diet. Individuals can look up ways to grease their cookware and flavor their food without using the same amount of oil and butter. They can also reduce the amount of fried food they eat.

Try A Low FODMAP Diet

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For irritable bowel syndrome patients, eating often leads to dramatic digestive symptoms. But restricting the consumption of trigger foods has also been shown to reduce the frequency of flareups in many individuals with food sensitivities. For those who have irritable bowel syndrome, the most common diet is called a low FODMAP diet. Doctors use a low FODMAP diet as the first clinical treatment recommendation for irritable bowel syndrome. FODMAP is the short version of a chemical name that describes certain fermentable carbohydrates found in foods all over the food pyramid. Unfortunately, it's not as simple as eliminating just one product or category of food. FODMAPs are divided into four groups. Some of the foods high in these carbohydrates include legumes, rye, wheat, onions, garlic, soft cheese, yogurt, milk, mangoes, fruits, agave nectar, honey, lychee, blackberries, and certain low-calorie sweeteners found in coffee substitutes or sugarless gum. Since many fruits and vegetables are on the list, individuals have to educate themselves and be conscious rather than just avoiding wheat and dairy.

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