IBS Tales Home
Header Image

IBS Tales Home > About IBS > IBS Foods

ibs foods

There is no set diet for IBS sufferers, and many sufferers find that they have their own individual intolerances and food triggers. However, one popular diet is the Heather Van Vorous eating for IBS diet, and on this page Heather explains how her diet works, what foods you should be eating and what foods should be avoided if you wish to try this particular approach.

Good Nutrition and Great Food When You’re Eating for IBS

By Heather Van Vorous

No, this title is not a contradiction in terms. It’s not only possible, but actually very easy to eat a healthy – and delicious - diet that will actively prevent IBS symptoms. There are, in fact, very clear guidelines to follow for how to eat safely for IBS, based on the well-established effects certain categories of foods have on the GI tract. The key word here is categories – if you’re like most people with IBS, the odds are you’ve been going crazy trying to figure which one specific food triggers your attacks.

The problem is, it isn’t a single food that causes attacks. It’s any food that is high in fat, insoluble fiber, caffeine, coffee (even decaf), carbonation, or alcohol. Why? Because all of these food categories are either GI stimulants or irritants, and can cause violent over reactions of the muscles in your colon.

So does this mean you can never again eat any of these foods? No, not at all. It just means you’ll have to recognize them as triggers, and eat them carefully, according to guidelines we’ll cover below. More importantly, you’ll need to focus on what you can and should eat, and the primary food category here is soluble fiber.

Soluble Fiber

You’ve heard of fiber, you’re pretty sure you know what it is, and you’ve probably had it recommended to you as beneficial for IBS. But soluble fiber? Is this something special? Yes, it is. Soluble fiber is the single greatest dietary aid for preventing IBS symptoms in the first place, as well as relieving them once they occur. Here’s the kicker. Soluble fiber is NOT typically found in foods most people think of as fiber, such as bran or raw leafy green vegetables.

Soluble fiber is actually found in foods commonly thought of as starches, though soluble fiber itself differs from starch as the chemical bonds that join its individual sugar units cannot be digested by enzymes in the human GI tract. In other words, soluble fiber has no calories because it passes through the body intact.

Soluble Fiber Foods – the Basis of the IBS Diet

As a general rule, the grain and cereal foods at the top of this list make the safest, easiest, and most versatile soluble fiber foundations for your meals and snacks:

Why is soluble fiber so special? Because unlike any other food category, it soothes and regulates the digestive tract, stabilizes the intestinal contractions resulting from the gastrocolic reflex, and normalizes bowel function from either extreme. That’s right - soluble fiber prevents and relieves both diarrhea and constipation. Nothing else in the world will do this for you.

How is this possible? The 'soluble' in soluble fiber means that it dissolves in water (though it is not digested). This allows it to absorb excess liquid in the colon, preventing diarrhea by forming a thick gel and adding a great deal of bulk as it passes intact through the gut.. This gel (as opposed to a watery liquid) also keeps the GI muscles stretched gently around a full colon, giving those muscles something to easily 'grip' during peristaltic contractions, thus preventing the rapid transit time and explosive bowel movements of diarrhea as well.

By the same token, the full gel-filled colon (as opposed to a colon tightly clenched around dry, hard, impacted stools) provides the same grip during the muscle waves of constipation sufferers, allowing for an easier and faster transit time, and the passage of the thick wet gel also effectively relieves constipation by softening and pushing through impacted fecal matter. If you can mentally picture your colon as a tube that is squeezing through matter via regular waves of contractions, it’s easy to see how a colon filled with soluble fiber gel is beneficial for both sides of the IBS coin.

As a glorious bonus here, normalizing the contractions of the colon (from too fast or too slow speeds) prevents the violent and irregular spasms that result in the lower abdominal cramping pain that cripples so many IBS patients. This single action alone is the reason you shouldn’t eat anything on an empty stomach but soluble fiber. Ever. The only foods you want to trigger your gastrocolic reflex are soluble fiber, as that’s the best way to keep those contractions (and thus your life) normal.

Try to routinely snack on small quantities of sourdough bread, rice cakes, homemade quick breads (pumpkin, zucchini) from IBS safe recipes, bananas, baked corn chips, etc. all day long, every single day. If you don’t have a chance to eat or you’re not that hungry, take a supplement such as psyllium powder, Fibercon tablets, Benefiber, or a glass of Citrucel (these are simply soluble fiber supplements – they are NOT laxatives, even though they’re often marketed as such).

Your goal is continual stability, and a steady ingestion of soluble fiber insures this. In the short run this strategy allows you to prevent problems from snack to snack and meal to meal, but in the end it adds up to long-term stability from day to day, week to week, and even month to month. You’re likely to find that the single best method for completely preventing IBS symptoms is basing your diet on soluble fiber foods. You can keep your colon stabilized each and every day by building all meals and snacks on soluble fiber foods.

Fat – The Bad Guy

Well, you probably knew this one. Most people quickly figure out on their own that greasy foods cause problems. High-fat foods are usually easy to identify, and after getting sick for the third or fourth time in a row after eating French fries or ice cream it becomes painfully obvious that fat is an IBS trigger. Have you been wondering why? Fat is the single greatest digestive tract stimulant. Nothing else will trigger a more powerful gastrocolic reflex.

For those of us already prone to wildly unstable colon contractions, this is bad news indeed. Interestingly, the type of fat doesn’t matter at all – saturated, monounsaturated, polyunsaturated, they’re all equal triggers. It simply makes no difference to your gastrocolic reflex if you’re eating lard or extra virgin olive oil. It will make quite a difference to your heart and your health in general, of course, but in terms of controlling IBS the less fat of all kinds, the better period. This doesn’t mean following a fat-free diet, by the way, but simply a low-fat one.

Danger – High Fat Foods Ahead

Please don’t read this list and assume that you can never again eat any of these foods, so life is no longer worth living. These are all triggers, yes, and some of them you will probably have to completely eliminate from your diet. BUT - others can be eaten in small quantities when you follow the guidelines coming up, many of the items listed have safer substitutes you can use freely, and there are quite a few tips and tricks for cooking with the nutritious foods on the list in a safe manner. So take heart, this isn’t the end of the world - it’s just the beginning of a better diet.

Meat, dairy products, and egg yolks are particularly dangerous for all aspects of IBS. In some people their high fat content causes violent, rapid colon spasms and triggers diarrhea. Alternately, for others their heavy animal proteins, complete lack of fiber, and very low water content can lead to drastically slowed colon contractions and severe constipation. No matter what IBS symptoms you’re prone to, these three categories of foods pose high risks and are really best eliminated from your diet altogether:

Fats are usually fairly obvious foods to identify, but not always. The worst culprits are those at the top of the list and many (particularly meat, dairy, egg yolks, and fried foods) can simply be eliminated from your diet entirely and your whole body will be healthier for it. I know the thought of this can be deeply shocking, but giving up these foods does not equal deprivation. Honestly, it doesn’t.

There are a great many easy substitutions that will let you cook and eat safely while still enjoying many of your traditional favorite foods. There’s also a lot of fun to be had in trying a wide variety of new ones. And when you’re tempted to indulge in a dangerous treat, just remember that everything tastes a lot less delicious when it’s followed by a vicious IBS attack.

There are also some hidden sources of fat to watch out for, cookies, crackers, pancakes, waffles, Frenchtoast, biscuits, scones, pastries, doughnuts, and mashed potatoes can all be sky high in fat (virtually always so at restaurants), so be careful. Give thanks for the recent fat-free craze that has given us supermarket aisles full of safe alternatives.

Insoluble Fiber – Good or Bad?

Both! Here’s the type of fiber everyone is familiar with – bran, whole grains, raw fruits and vegetables (note the exceptions under Soluble Fiber), greens, sprouts, legumes, seeds, and nuts. In short, the healthiest foods in the world, and what everyone should be eating as much of as possible. Right?

Well, right, except for one small problem. Insoluble fiber, like fat, is a very powerful GI tract stimulant, and for those of us with IBS this can spell big trouble. Unlike fat, however, you cannot simply minimize your insoluble fiber intake, as this will leave you with a seriously unhealthy diet. It’s a paradox, but the conflict can be solved fairly easily.

Insoluble Fiber Foods – Eat with Care

Once glance will tell you these are the best (and tastiest) foods around, but your colon simply can’t handle it if you eat them with abandon. You can (and absolutely must) eat them, but within the IBS dietary guidelines. Treat these foods with suitable caution, and you’ll be able to enjoy a wide variety of them, in very healthy quantities, without problem.

In general, if a plant food (no animal products contain fiber) seems rough, stringy, has a tough skin, hull, peel, pod, or seeds, be careful. This is not a comprehensive list by any means but it should give you the general idea. Whole wheat flour, whole wheat bread, whole wheat cereal Bran whole grains, whole grain breads, whole grain cereals (the two big exceptions here are oatmeal and brown rice, both of which are very safe whole grains).

Here's the list:

Never eat insoluble fiber alone or on an empty stomach. Always eat it with a larger quantity of soluble fiber, and you will keep your gastro colic reflex stable. What does this mean in practical terms? Cook some diced vegetables into a low-fat sauce for pasta, stir-fry veggies into a fried rice, or blend fresh fruit into a smoothie to drink after a breakfast bowl of oatmeal. For fruits, vegetables, and legumes in general, peeling, chopping, cooking, and pureeing them will significantly minimize the impact of their insoluble fiber.

Make soups, drinks, sauces, breads, and dips from your veggies and fruits instead of eating them whole and raw. For beans and lentils, cook and blend them into sauces, dips, soups, or spreads their insoluble fiber is found in their outer skins and their insides are actually rich in soluble fiber. For nuts, finely grind and incorporate them into breads or cakes with white flour, which gives a safe soluble fiber base.

For bran and other whole grains, eat them in small quantities following soluble fiber foods – have a little whole wheat dinner roll after a big sourdough one, or mix a small amount of fat-free granola into a large bowl of cream of rice or Corn Chex cereal. For raw fruit and green salads, eat them at the end of a soluble fiber meal instead of at the beginning. For all insoluble fiber foods, start with small quantities and gradually increase your intake, making sure you follow these guidelines.

I’m confused! How can the same food have insoluble and soluble fiber?

Most all grains, cereals, legumes, and tubers have an outer insoluble fiber layer, and a soluble fiber interior (and the same is true for some fruits and vegetables, such as apples and zucchini). It’s very easy to actually see this with your own eyes. If you take a cooked grain of brown rice, wheat berry, kernel of corn, potato, or bean you can separate the tough exterior (the bran, skin, or shell) from the creamy interior. When the bran is removed from wheat berries and they’re milled the result is white flour; when the bran is removed from brown rice the result is white rice.

There aren’t many similar common commercial processes that remove the insoluble fiber exterior from legumes, fruits, or vegetables, but finely blending, pureeing, or peeling these whole foods will greatly minimize their trigger risk. Wheat in particular causes confusion for many, many people with IBS who are unsure about whether or not it is a safe food for them. There is no flat yes or no answer to this concern because, as we’ve just learned, it depends.

Whole wheat, with its outer layer of bran, is high in insoluble fiber. This means that it’s a trigger. That’s why whole wheat bread, whole wheat cereals, and bran can cause such awful problems for people with IBS. However, when you remove the bran from whole wheat you end up with white flour (the regular kind you can buy in any grocery store, that you using in baking cookies, breads, muffins, etc). Though this is still wheat flour, it is not whole wheat flour, and this makes a world of difference.

White flour contains no insoluble fiber but it does have soluble fiber, which is the stabilizing force of the IBS diet (just picture the thick gel that results when you dissolve a piece of white bread in a glass of water). This is why white breads are such great safe staples. When you read the ingredients on packaged foods they might not specify if the wheat flour used is “white” or “whole”, but it’s usually pretty easy to tell.

For breads, a brief glance will tell you if there is whole wheat in it (you’ll see little brown flakes). If the bread is pure white, like French or sourdough, you’re safe. For most crackers, pretzels, muffins, etc. only white flour will be used. The exception is health food store products, which are likely to use whole wheat. However, they will almost always tout this fact so you won’t be left wondering.

The whole wheat (and other insoluble fiber) intolerances so common to IBS are markedly different from true food allergies. If you’re allergic to wheat, it will make no difference if the grain is left whole or refined by removing the bran. In addition, with many allergies even minuscule quantities of the trigger, whether eaten with other foods or alone, can trigger violent reactions. Fortunately, with IBS this is rarely the case, so we just have to be careful with whole wheat and other insoluble fibers.

If we do take care we can easily and frequently eat them in small quantities when they’re combined with high soluble fiber foods. In addition, with wheat, once the bran has been removed so has the risk of an IBS attack, and this gives us great dietary freedom when it comes to white breads and other refined wheat flour foods.

Some fruits and vegetables are particularly troublesome for IBS

Sulfur-containing foods (garlic, onions, leeks, broccoli, cauliflower, cabbage, asparagus, and Brussels sprouts), in addition to their high amounts of insoluble fiber, also produce significant gas in the GI tract and this can trigger attacks. As with all other fruits and veggies, however, these are extremely nutritious foods with significant health benefits, so they need to be treated with caution but definitely not eliminated from your diet.

Acidic foods (citrus fruits and cooked tomatoes) should be treated with extra care as well, as their acidity can cause both upper and lower GI distress. Once again, follow the rules for insoluble fiber and eat these foods in smaller quantities incorporated with soluble fiber – but please do eat them.

Fructose, a fruit sugar, can cause gas, bloating, and diarrhea (this is typically not true for sucrose, or plain table sugar). Fruit juices, particularly apple and grape juice, are often sky high in fructose and even more problematic than whole fresh fruit. It’s simply much easier and faster to drink a large glass of juice (and ingest a great deal of fructose) than to eat an equivalent amount of whole fruit. So treat juices as you would insoluble fiber and drink them carefully, with soluble fiber foods.

Other Pesky Creatures to Avoid

Coffee – both regular and decaf – contains an enzyme that’s an extremely powerful GI tract irritant. Go cold turkey today and drink herbal teas instead. Caffeine is a GI stimulant and should be avoided, especially in higher doses.

Alcohol is a GI irritant and often triggers attacks, especially on an empty stomach (though small amounts of alcohol used in cooking are fine).

Carbonation in soda pop and mineral water can cause bloating and cramps.

Artificial sweeteners, particularly sorbitol, can trigger pain and diarrhea. Artificial fats, namely Olestra, can cause abdominal cramping and diarrhea in people who don’t even have IBS imagine what it can do to you. MSG has acquired lots of ugly anecdotal evidence against it regarding all sorts of digestive upsets. It can simply be avoided, so why take a chance?

Size Matters

No matter how safe any food is for IBS, eating a huge portion of it in one sitting can trigger an attack. Your gastrocolic reflex gains strength in direct correlation to the number of calories you consume in a meal. While this makes it easy to see why high fat foods causes problems (fat is more than twice as calorie-dense as carbohydrates and proteins) it also means that bingeing on anything carries serious risks for those of us with IBS.

So don’t kid yourself that when your friend breaks out a pint of ice cream and a spoon that you can do the same with fat-free sorbet. It’s not just ingredients, but quantity too. Size really does matter. Keeping your portions small has some fringe benefits, particularly in that it should make it easier to eat more frequently, and this is a helpful strategy for maintaining a constant intake of soluble fiber.

Unfortunately, the Western world has gotten used to 'supersizing' just about everything we eat, and this can be a hard habit to break. One thing to try at home is serving yourself on salad plates and soup bowls, so that visually you don’t feel faced with a skimpy meal. Remember too that you can always take a second small portion after you finish the first one, as long as you eat at a slow-to-moderate pace and you still feel hungry.

This is a great way to keep from over-serving yourself initially and then feeling obligated to eat everything on your plate even if you’re full (a “don’t waste food” lesson ingrained in most of us as children). Snacking on small amounts of food throughout the day will keep you from getting ravenous and then over-eating, which can trigger an attack. At restaurants make a point of dividing your plate in half the moment you’re served and take that portion home with you for a later meal.

Once you develop this habit you’ll likely be astonished to realize how oversized most restaurant meals are, and it will be clear why it’s so common to suffer an attack if you eat all that food at one sitting. I have a few favorite restaurants (Ethiopian and Middle Eastern) whose dinner portions are so generous I actually get three complete meals out of them. Even someone without IBS is likely to feel pretty uncomfortable if they down that much food at a one dinner.

There’s another aspect to portion control that has some happy possibilities for IBS. The risk of trigger foods can be tremendously minimized if they’re eaten in tiny quantities following soluble fiber. In this regard, it is as much how you eat as what you eat that will help you manage your symptoms. While this is most important as a tool to allow you to incorporate all those healthy insoluble fiber foods as often as possible, it’s also a means of treating yourself to a “mini splurge” every once in a while.

Let’s say you’re well-stabilized and just dying for a chocolate bar. Eating a full-size candy bar as a snack when your stomach is empty will likely wreak havoc and send you into an immediate downward spiral of attacks (why? because it’s sky high in fat and dairy, and has very little soluble fiber). However, if your symptoms were well under control and you instead decided to treat yourself to a snack-size individual candy bar (a tiny portion equals a tiny quantity of fat/dairy triggers) for dessert, immediately following a nice low-fat, high soluble fiber meal, you’d likely do just fine.

I eat solid chocolate almost every day in this manner. (Of course, this may just be sheer willpower because as God is my witness I will not go through life without chocolate, but I think this is probably the less likely explanation.)

Whatever your favorite trigger food, this strategy gives you a good means of allowing yourself the occasional small indulgence. IBS food intolerances are, fortunately, not like food allergies, where the quantity of a trigger (say, peanuts) may not matter. For this we can thank our lucky stars, as it means that few things are truly forbidden to us as long as we follow some common sense rules and exercise a little self control.

Will eating for IBS make me fat?

You’re not alone if you’re wondering whether eating safely for IBS will lead to excess weight gain. Rest assured, it won’t. The basis of the IBS diet, soluble fiber, has no calories at all as it is indigestible. High soluble fiber foods are virtually always high in complex carbohydrates and low in fat. This is a good thing, as the healthiest diets in the world, associated with the lowest obesity rates, are those highest in complex carbohydrates and lowest in fat and protein (particularly from animal products).

This fact completely contradicts the current and misguided popularity of high protein/low carbohydrate fad diets. Tellingly, the obesity rates for cultures with high carb/low fat and protein diets (primarily in Asia) are a fraction of the obesity rates in the Western world. Americans average only 40-50% of diet from carbohydrates – but most Asian nations average 60-75%. The US national obesity rate is now one of the highest in the world, at 35% for adults and 20% for children. The average Asian country’s obesity rate is just 2-3%. Striking, isn’t it?

It is simply very difficult to eat enough high soluble fiber foods (they’re very filling) to gain weight while still keeping your diet low fat. The high soluble fiber diet necessary for controlling IBS should actually result in weight loss - if you're overweight. If your weight is already normal it won't result in weight gain unless you significantly up your portion sizes, which would likely trigger an attack, or gorge yourself on refined sugar foods that have no soluble fiber to fill you up.

The IBS diet is essentially low-fat vegetarian-based, plus chicken breasts and seafood. Eliminating the meat, dairy, fried foods, and soda pop drastically lowers the calorie count for people who switch from a 'typical' Western diet. Upping your soluble fiber food intake will increase your calories from complex carbohydrates, but these are much less calorie-dense than all the fats you’ve eliminated. It also takes more energy for your body to store excess carbohydrates, versus excess fats, as body fat, so you have to eat more carbohydrate calories than fat calories in order to gain weight.

Carefully incorporating as much insoluble fiber as you can tolerate will not add any significant calories at all. Plus, both types of fiber are very filling, and will help with appetite control. Eating small portions frequently, important for minimizing the risk of attacks, also helps keep you filled without having to eat as much.

Finally, please realize that soluble fiber is extremely beneficial for a lot of health problems besides IBS. It not only regulates and normalizes colonic activity, it also lowers LDL ('bad') blood cholesterol levels and the corresponding risk of heart disease, prevents colon cancer, and improves glycemic (blood sugar) control in diabetics by slowing the digestion of carbohydrates and subsequent release of glucose into the blood.

It also helps prevent blood vessel constriction and the formation of free radicals, both risk factors for heart attacks, by slowing the absorption of fat and carbohydrates into the bloodstream. Best of all, it really and truly does dramatically help prevent IBS attacks. So don't be afraid of it, and don't worry about weight gain or difficult weight loss.

Eating for IBS should safely and easily normalize your weight, helping you lose pounds if you need to. And if you’re looking for a weight gain, finally having the knowledge of how to eat without fear should allow you to up your calorie intake significantly and add on the pounds you need for good health.

Heather Van Vorous is the author of Eating for IBS and The First Year: IBS. She has had IBS since childhood and is the president of Heather and Company, an organization dedicated to meeting the needs of IBS patients through education, products and services.