Eating For IBS: Soluble Fiber

by Gena on July 27, 2010

Hey guys!

Seems like the general consensus is that you’re pleased with my balance of higher fat and lighter recipes – though requests for more calorically dense recipes have been noted!

I got the following email yesterday:

Hi Gena,

Have you heard of the book Eating for IBS? Maggie (The Salad Girl) wrote about it on her blog recently, and since I know you overcame IBS, I wanted your opinion. The book basically suggests that eating soluble fiber at the start of each meal is the key to IBS management. Do you think this is true? What are sources of soluble fiber (as opposed to insoluble)?


Thanks for asking, Cindy! I am indeed familiar with Heather Van Vorous’s book (though the last time I looked at it, I was in college). I tried a number of her suggestions at the time; they were many in a long succession of things I tried.

The main premise of Eating With IBS is that soluble fiber is the key to IBS management. Van Vorous posits that eating too much insoluble fiber and not enough soluble can immediately aggravate IBS symptoms (I think she’s right). She also takes care to emphasize that one must get a balance of soluble and insoluble fiber through diet: insoluble fiber can be an irritant, but it can’t be avoided.

So what exactly are soluble and insoluble fiber, and how are they different? To explain this, I’m afraid I’m going to have to get a little graphic: soluble fiber’s main function is to form a viscous, gel-like substance in the large intestine, which coats waste matter as it passes through the GI tract. This gel prevents emptying that is either too fast (diarrhea) or too slow (constipation). It also adds bulk to your stools, which is important regardless of whether you suffer from diarrhea, constipation, or both. Soluble fiber also prolongs stomach emptying, so that food is digested more slowly (this is part of why oats keep us full for so long!), and it binds to fatty acids (which is why barley and oats are famous for helping to lower bad cholesterol).

Soluble fiber isn’t found in the foods we most readily think of as fibrous (such as raw greens or vegetables). Instead, it’s most predominant in starchy foods, including oats, barley, sweet potatoes, winter squashes, and white breads. Other sources are:

Pasta (white, not whole grain)
Corn meal

Insoluble fiber, by contrast, can’t dissolve in water. It lends bulk to stools, but no viscosity, which means that, eaten in excess, it can slow elimination down. It can also cause elimination to speed up too much (because our bodies can’t handle that much bulk at once). It’s what we find in raw veggies, whole wheat foods, bran, granola, crucifers, and most fruits.

According to Van Vorous, IBS management is contingent upon

(a)    getting soluble fiber at each meal
(b)    eating soluble fiber before insoluble fiber
(c)    avoiding excess insoluble fiber

No doubt this is very helpful for some folks with IBS. I myself tend to find starchy foods pretty easy to digest, and I’ve had clients who agreed. But of course, there’s really no perfect science to managing IBS. While getting increased fiber on the whole seems to work for most people with IBS, it’s hard to say whether soluble fiber intake will be a silver bullet for everyone. In fact, some people with IBS (or other digestive diseases, like IBD) find that starch can be problematic, and thrive on low-starch diets. So, the best I can say about the theory is that it is probably a great answer for some folks with IBS; to find out whether that’s you, you’ll need to listen to your body.

Of course, this whole discussion does present me with a good opportunity to chat about fiber balance on the whole. One of the most common complaints I hear among new raw foods lovers is that they’re bloated and not eliminating well, even though they’re eating a ton of raw veggies. The problem often seems to be that they’re eating tons of insoluble fiber (in the form of raw fruits and veg), without any soluble fiber to balance it (because they’ve fearfully abandoned all starches and grains). Eating just a bit more whole grains, legumes, and starchy foods is often an immediate source of relief. On the other hand, some of my clients who seem to eat a lot of grains, but not quite enough fresh veggies, also seem to benefit from a more balanced approach; in this case, it means eating more insoluble fiber, rather than soluble. As with most things, balance is key.

So, Cindy, my advice is this: eat soluble fiber at the start of your meals, and see if it helps. Be sure to eat insoluble fiber, too, and be mindful of how the ratio affects you. But don’t be afraid to try other things if these methods don’t help you. All books on IBS offer possible courses of action, but none of them offer definitive solutions. What matters is that you educate yourself about options, and keep an open mind until you begin to feel relief!


Print Friendly
Be Sociable, Share!

{ 56 comments… read them below or add one }

Evan Thomas July 27, 2010 at 3:40 pm

I’m all for recommending carbs ;-)
I find it interesting white pasta has soluble fiber while whole grain has insoluble; wouldn’t the whole grain at least have both forms? Because I couldn’t imagine changing or adding a new fiber simply by stripping the grain.


Gena July 27, 2010 at 3:42 pm


I’m not certain, but I would imagine that there is some soluble fiber in whole grain pasta. I think the point is that MOST of the fiber in whole grain is insoluble.



Lisa July 27, 2010 at 3:48 pm

Great post that comes a great time. Even though I’ve been eating high raw since March, yesterday I had a raw veggie chopped salad that was about the size of a small African country…. and was in agony until this morning, and even STILL am having some digestive issues (mostly bloating and discomfort). I couldn’t figure out what was wrong with me for the past 24 hours and have been racking my brain thinking about something I might have “accidentally ate”. Duh, perhaps too much insoluble fiber! Thanks Gena


JL Goes Vegan July 27, 2010 at 3:50 pm

This is a great post. I have a friend who is trying to manage IBS through diet. I’m going to send her a link to the post right now!


Emily July 27, 2010 at 3:58 pm

Gena, thanks so much for this post! I am an IBS sufferer too and bought that book in the past year but haven’t felt like it totally solved my problems. The information was great but I think that what you said makes more sense and fits in better with the eating habits and lifestyle that I have.

thanks again:)


Tamara July 27, 2010 at 4:14 pm

Avoiding Dairy has been my #1 relief from IBS symptoms. #2 relief is limiting SOY. Also, eating consistently (as if you have a bowl of oats every morning, keep doing that) helps. When I travel, or when I shift my diet, I always feel worse. When I do not have a great deal of soluble fiber, I think I feel worse. I will definitely monitor this one now to see how I do either way.


elizabeth July 27, 2010 at 5:58 pm

I’m wondering if the cause of traveller’s constipation is not the shift in routine but the fact that flying is so dehydrating? This was the bane of my existence (to a point where I feared travelling) until I learned to manage it, 1. by not eating on the plane, not matter what, no matter how far I’m travelling, 2. not drinking alcohol before or during a flight, 3. forcing myself to drink tons of water the whole flight, even if I’m not experiencing thirst. If I do this, I find I can still shift my routines a bit, enjoy the local cuisine, and not fret if I don’t find a juice bar. I’m actually appalled when I learn people travel with their Vitamixes and a suitcase full of raw snacks. But that’s me being horribly judgmental.


Gena July 27, 2010 at 9:12 pm

I think it is the dehydration, E, coupled with not enough mobility (so peristalsis gets even slower). I also avoid eating on planes unless I’m REALLY hungry.

And I’m with you on traveling with appliances. I once read the account of a raw foodist who spent eight days in Paris lugging around her portable blender and trying to strain juices. I may not be eating the entrecote and chevre in gay Paris, but my trips there typically involve pounds of baguette, mountains of chocolate, and liters of coffee, and I wouldn’t have it any other way.


Lulu June 29, 2013 at 6:31 am

I love your “pounds of baguette, mountains of chocolate, and liters of coffee” description :) I love that you eat healthy and do not fear unhealthy foods! By the way, that chocolate mountain sounds divine enough for me to find it myself and devour it :P


Ameena July 27, 2010 at 4:52 pm

As a IBS sufferer I can say that starchy foods like potatoes, rice, gluten-free tortillas, corn, etc. work the best for me. I also agree that avoiding dairy and soy have helped 99% of my symptoms.


Kristina July 27, 2010 at 4:58 pm

this is fabulous… I have bookmarked this page to return to as a reference…

thank you for a great amount of important information!


Emma July 27, 2010 at 5:10 pm

Thanks so much for this Gena. I don’t have IBS but have often struggled with poor digestion and constipation (Maybe tmi but whatever :)) I always thought the problem was that I wasn’t eating enough bulk and always considered that fruits and veggies/bran were what I should be looking at, but now thinking about it I was probably doing the completely wrong thing. I need to ensure to eat enough soluble fiber from starches and nuts too.
Thanks again for the info.


Sarah July 27, 2010 at 5:27 pm

Yay, what a great post! I tried this diet for a while too and I am in total agreement that both soluble and insoluble fibre foods are necessary- especially for IBS-C. I do find for me that there is a definite link between slower transit time and a higher intake of insoluble fibres. My GI tract loves sweet potatoes and roasted roots, especially when accompanied by salads.

I’ve just bought a juicer and beginning to experiment with what combos suit my body. But i guess with juicing all the fibre’s been removed so it should be easy on my tract?

I’d like to experiment with smoothies again, so if I try combining them with a soluble fibre like avocado or bananas then, in theory, my system should be ok?

How I wish IBS was straight forward! I get emails from people asking how I manage my IBS but truth me told, I’m still figuring it out. As you can see! It’s a journey and I’m enjoying the ride, for the most part. Especially since it means eating lots of beautiful, vibrant foods! :)

Thanks for your usual informative, balanced post Gena. You’re awesome xxx


Christie {Honoring Health} July 27, 2010 at 5:38 pm

Great post, Gena.

Funny thing is, this was the very topic of school this week and I was just telling my husband about the two types of fiber yesterday!


Anna @ Newlywed, Newly Veg July 27, 2010 at 6:15 pm

My husband has really bad IBS. He’s gotten better about manageing it over the past few years, but it still flares up sometimes…I’m going to show him this! Thanks Gena!


Christine (The Raw Project) July 27, 2010 at 6:29 pm

Great post and it clears up a lot. Increasing insoluble fiber gave me huge improvements, but I also have to be careful not to over-do them and keep balance. And quinoa is one of my favorite ways to do that. :-) Thanks!


bitt July 27, 2010 at 7:50 pm

One of the main reasons I started eating more raw foods was for constipation. It really helped a first. Then after eating this way for a long time it started up again. The solution for me is to eat at least a half cup buckwheaties (soaked and dried) a day. I am not sure what type of fiber that is, but it works. Popcorn is also great for me. But my needs have changed at different times, and so having all the tools and knowledge to make changes is so important.


miss alix July 27, 2010 at 8:03 pm

wow reading this makes me happy. i have dealt with ibs on and off for many years and while i know certain triggers to avoid, i definitely didn’t know the effects of soluble and insoluble fiber! seriously helpful.


Katie July 27, 2010 at 9:00 pm

To throw my two cents in, I have found Breaking the Vicious Cycle by Elaine Gotschall to be an incredible instrument in my healing from IBS. I certainly don’t think the diet it outlines (the Specific Carbohydrate Diet, SCD for short) works for everyone 100% of the time, but honestly I think when people really follow it for a while, it works for most. The improvement I’ve had is so significant — I just can’t recommend it high enough. It seems to me that it is a helpful diet for people with autoimmune disorders, and literally everyone in my family has at least two autoimmune disorders/diseases. I hope that if others have tried some of these options and haven’t yet found success, or even if they want to just begin the process of figuring out their IBS (or other digestive disorder) they give it a try. It takes great commitment, but I’ve never been healthier in my life.

Gena, thanks for offering more options to the many who suffer from IBS. It’s always helpful to hear about others’ journeys.



Gena July 27, 2010 at 9:09 pm


Thanks for weighing in. Just to offer my two cents on the SCD. I think it’s fine if you believe in it, but it’s an extremely hard diet for a vegan to follow, because it excludes grains and legumes. These are often the bedrock of energy density within a vegan or vegetarian life (not to mention rich sources of nutrition); without them, vegans are essentially relegated to a diet of vegetables and nuts. So I think it’s an approach that’s better suited for people who wish to consume meat, fish, and dairy than for vegans.



Katie July 28, 2010 at 1:03 am

Thanks for your thoughts Gena.

I just wanted to add a quick follow-up. I completely agree that it would be a huge challenge for a vegan to follow this diet… but I also have found that though the diet does eliminate grains (which after much trial and error seem to be the root of most of my IBS/autoimmune flare-ups), I have found enough variety in the legume/bean options. Just to clarify, one can eat most legumes on the SCD, but they do have to be soaked overnight. I definitely respect and understand your views, just wanted to share my experience if someone out there is at the end of their rope. I appreciate your thoughts on this and if you have further criticism of course would love to hear it; I’m always eager to learn from those who have a deeper knowledge of nutrition than myself (and of course I want to be sure I am living/eating as ethically and healthfully as possible : )



Gena July 28, 2010 at 7:57 am

You are very respectful, Katie!

I know that exceptions are allowed within the bean group — though as it was described to me, those exceptions were added a little grudgingly, and the real intent is for polysaccharides to be eliminated. It’s just so unbelievably contradictory to my own thinking (which is that starches and complex carbs are really crucial for energy, and that starches can also help in IBS management) that it’s hard for me to comment, but hey, whatever works!



Alex March 8, 2012 at 2:10 am

I have Ulcerative Colitis. I’ve been on the Specific Carbohydrate Diet for a few months now and the results have been amazing. I’m practically symptom-free. It definitely requires very strict following; one wrong food and you’ll be back to the bathroom every 5 seconds… Good luck to everyone, and sorry to those who this diet hasn’t worked for.



Nola @ The Zetetic Gamin July 27, 2010 at 9:31 pm

I just have to chime as one for whom Eating for IBS was super helpful! Definitely helped me transition from months of non-stop pain and bloating to being pretty darn comfortable most of the time.

Over the years I’ve learned that quality, gluten-free insoluble fiber is really important (sweet & white potatoes, green peas, squash, & the like) – I don’t get the same relief over the long haul with anything processed (pasta, tortillas). I also find that the overall quality of my diet (mostly fruits, vegetables with some beans, grains, nuts & seeds) makes a huge difference, as does lightly cooking food & limiting fat (especially when things get rocky).


Maggie July 27, 2010 at 9:49 pm

Great perspective on this (and loved your descriptions)!


Averie (LoveVeggiesAndYoga) July 28, 2010 at 1:22 am

Wow just read all the comments…and I get TONS of poop related emails every week from readers, yes, why? Not sure….I never post about poop on my blog but everyone writes to me about it! I dont have IBS but I have food allergies. Food allergies for me behave in many ways like I’m sure people with IBS that I have to be SUPER careful about what I eat unless I want to throw my digestion for a complete 180.

I’ll be honest, I never really paid much attn to the diff kinds of fiber since I have been living under a rock :) I knew they existed but I never committed them to memory and this was an incredibly helpful post, Gena.

Not to mention, when ppl write to me about going raw and being bloated/sluggish digestion, I now have a much more plausible answer to give them as to what’s happening.

Thanks for this post! :)


Jackie (Peaces of Earth) July 28, 2010 at 2:20 am

Great info, Gena!!! This is extremely helpful and a great reference when people ask questions about raw. I have a friend with IBS and I’m sure this would help her a lot also. I have a distinct memory of her popping IBS pills while eating Taco Bell. I think this is a better route. :)


Anne July 28, 2010 at 4:38 am

Thanks so much for sharing your knowledge and experience – and for having the courage to be a little bit graphic too :-). Poop is so natural – but never easy to talk about, even after having been to many doctors I still find it difficult to talk about “elimination” and patterns of going to the bathroom, haha…Great post :-)


Metta July 28, 2010 at 9:06 am

Very helpful post, and explains a few things for me/my body. I’ve seen soluble vs insoluble fiber broken down before, but it never really stuck like your explaination. It really is a balance of getting just the right amount of what is needed to keep the bowels moving. For me it is eating enough grains, but not too much, along with pleanty of veggies and water, and some nuts/seeds.


fartygirl July 28, 2010 at 10:07 am

I’ve read about this theory from many IBS sources. One of my Crohn’s friends also claims the soluble over insoluble is best for digestion. All I can add is my own experience.

For me, it’s never made a difference whether I eat soluble or insoluble fiber. Many soluble fibers – like oats – really bother me. Meanwhile, a breakfast of sauteed broccoli or raspberry smoothie will go down smoother.

The things that really work for me are chia seeds, beans, and probiotics. They have really made a huge difference in “elimination” and overall bloat and gas.

So thank you for the chia pudding recipes! It’s the perfect IBSser’s brekkie.

Ultimately – everybody’s different! As always, you keep that mantra mindfully in your posts. And ditto on your ability to talk about the gross stuff without going too graphic. You got grace, lady. :)


Gena July 28, 2010 at 2:37 pm

That’s great about chia seeds. Sauteed broccoli at breakfast would probably not be the wisest choice for me, if I wanted any human contact at all during my day :)


B July 28, 2010 at 10:33 am

Gena, Thanks so much for the information… I’m not diagnosed with IBS but do experience many of the symptoms from time to time (especially when traveling.) Question: Do nuts contain more soluble or insoluble fiber?
They are a daily party of my diet but I do notice if I eat too many I have terrible stomach pain. Does this happen to anyone else?


flsseaton July 28, 2010 at 10:45 am

I’m one of the friends referenced above (thanks for the link, JL!). I was recently diagnosed with IBS after about 3 or 4 months of test after test to rule out everything else. I was thrown for a loop at the final diagnosis and none of the doctors I saw had any recommendation other than medication. I found “Eating for IBS” at the library and was utterly confounded. The advice seemed the exact opposite of the South Beach diet which I found extremely successful in shedding 40 unwanted pounds and maintaining a healthy weight for the past 6 years. I did eliminate dairy and red meat and honestly, I don’t miss it. (Yet. I have my doubts about passing up the cheese the next time I’m in Europe.) I had already given up caffeine and cut way back on alcohol and have found some relief. I still have flare ups though. I haven’t found the right combination of foods for me, but I just started the journey this year so the information you provided is much appreciated!


Kenzie (HealthyPurpose) July 28, 2010 at 10:45 am

good info! never really got the difference. I try to have a balance, but am definitely more heavy on the insoluble (veggies, right?) kind.Then again, that’s probably well balances with all my avocados and bananas!


Danielle (Runs on Green) July 28, 2010 at 12:38 pm

I don’t have IBS but I can attest to the fact that fiber helps move things along hah. And thanks for bringing attention to the different kinds of fiber. A lot of people think that by eating those Fiber One bars and other “added fiber” products, then they’re good to go. But most of that stuff has chicory root extract which is alllll soluble fiber…and I won’t even get into the whole “is this healthy because it has added fiber but 200000 chemicals” thing :)


Annie@stronghealthyfit July 28, 2010 at 1:27 pm

Interesting convo! Good stuff to know.


Karen July 28, 2010 at 1:40 pm

Wow, Gena…you’ve outdone yourself with this clear explanation! While I don’t have IBS, I do occasionally suffer from digestive issues, suspecting that an overdose of total fiber may be culprit. I consider myself nutritionally-intelligent, and am aware of the need for both types of fiber, yet your analysis finally puts the issue into perspective for me. BIG thanks for the actionable advice. You are my favorite health educator, Gena!


MaryZ July 28, 2010 at 2:29 pm

This could not have come at a better time! I have been suffering the past few days with bloating and constipation. Could not for the life of me figure it out since I have been eating mostly fruits and veggies. Now I get why this happens to me occassionally…too much insoluble fiber and little or no soluble. Thanks again Gina for an awesome read!


Kat (My Fruity Life) July 28, 2010 at 2:29 pm

Your posts are always so timely! I feel like this could’ve been written for me as my digestion and bathroom trips have been less than stellar. I never need an excuse to eat more quinoa and sweet potatoes!


Mimi (Damn the Freshman 15) July 28, 2010 at 3:31 pm

I don’t have IBS, but I have been really friggin uh…backed up and bloated…lately. I will try this and see if it helps. Your posts are always so timely.


Maria July 28, 2010 at 8:38 pm

Gena, thanks so much for this post. I have suffered from IBS for the last several years and feel like I’ve tried everything. I’m going to explore some of the methods you describe in this post and also try your suggestions. Totally helpful!



Sarah July 29, 2010 at 8:19 am

I eat bran (fiber one cereal) and fiber bars ALOT. Usually the sng flavor and fiber bars or the fiber one brand ones. But thats basically it for fiber, besides broccoli and such.

What are some fruits and veggies that have soluble fiber in them?


callie July 29, 2010 at 9:46 am

Finally – it makes sense to me!

I’ve only read about insoluble/soluble fiber a million gazillion times and yet, I never really understood the difference and importance of both. I’m so glad you mentioned getting backed up, due to a lack of soluble fiber in the diet… It’s all starting to make sense now. Thanks for smartly summing up the difference and importance!


Andrea (Off Her Cork) July 29, 2010 at 3:28 pm

Gena this post was so informative! Even if someone doesn’t suffer from IBS, knowing about different kinds of fibers can only be of benefit. :)


jraw July 30, 2010 at 2:24 am

hi gena,
it’s funny, i don’t suffer from ibs but since i’ve gone raw i’ve started suffering from constipation big time. it’s really weird. i do eat 2 bananas and an avocado a day but maybe it’s time to add some more?
anyways, it’s great to find someone talking about constipation with raw…i’ve totally felt like a freak about it this whole time!


Kelly July 31, 2010 at 7:51 pm

I hardly eat any soluble fiber for my severe IBS . I eat mainly insoluble fiber but I still have severe constipation. I avoid triggers too. What gives?


Gena July 31, 2010 at 8:25 pm


In that case, I think you just proved the point of the post?



Sylvia August 19, 2010 at 9:10 pm

In your opinion, is it okay to combine fruit and oatmeal or nuts and oatmeal?


Gena August 19, 2010 at 10:38 pm

In my opinion, it is.


Kelly August 21, 2010 at 8:56 pm

I tried eating enough soluble and insoluble fiber for my IBS but it didn’t help.


Celene March 16, 2011 at 3:35 pm

I guess everyone really is different. I learned the opposite. Pasta, bread, starchy foods….they send me running for the bathroom. It’s horrible. I lived my life with no control and no idea. As soon as I eliminated processed carbs…no more symptoms (didn’t figure that out until mid life). I read the recommendations for IBS (high carbs) and was shocked! I would think this would cause some people harm….I know it would do some damage to me. I had no idea they could be a cure.


Jasmine Flower November 30, 2011 at 11:18 pm

I am a huge fan of fiber. As an IBS sufferer and a health conscious person, I know fiber does all kinds of good things for me, including keeping me regular which sounds silly but isn’t so funny when a week passes and you feel like you’re about to explode. I was recommend the Lady Soma Fiber Cleanse by my doctor – and this is a fiber like no other. It is amazing. Each dose contains natural, soluble dietary fiber extracted from the seeds of the cluster bean.

It is 100% natural fiber.I had never heard of Lady Soma products, but i am so glad they were recommended. So I am recommending them to you. . .its an excellent choice for maintaining regularity and supplementing you


bitt February 22, 2012 at 1:16 pm

OK I’m on this old post now. Where would you put chia and flax in terms of fiber? What type are they? Thanks.


Chris July 27, 2012 at 7:25 am

Great post,I have had IBS for the last five months and have since contacted two doctors without much assistance.I have therefore taken the option of diet where soluble fiber is a priority,hope will get well.


Maureen Phillips March 14, 2013 at 5:31 pm

A friend of mine suffered from what she thought was IBS for many years and started watching her fibers and felt a little better. Then she heard about the papya seeds & honey cleanse for parasites that can be living in your intestine and cause symptoms like IBS she did the cleanse which consists of chewing the papya seeds and swallowing them with honey for 10 days since then she can eat anything she wants and doesn’t have to worry about the different types of fiber.


Anonymous March 20, 2014 at 1:35 pm

Hi– I ve ibs wit dirhae — kindly recommend foods to eat n treatment— thanks


Leave a Comment

{ 4 trackbacks }

Previous post:

Next post: