I am frequently asked the question, "Does eating raw vegetables and salads aggravate IBS?" Not necessarily a question that a PubMed search is going to shed any light on because no one is going to pay money to do a study to see if eating salads makes people with IBS feel worse. The answer that I gave is that over the years I have frequently heard from many IBS patients that they have found that raw vegetables and salads do not agree with their systems.
Why might this be the case? Certainly uncooked vegetables require more work on the part on the digestive system as it has to break down food components and deal with the fiber content of the produce without the benefit of heat to start the process for it. On the other hand, can it just be that when one is eating salads or raw vegetables, one is simply eating a larger volume of produce, thus increasing gas and osmotic "load", along the lines of the FODMAPs diet theory? These are just my guesses and I am open to anyone else who might have a theory.
I hope no one reading this thinks to themselves, "okay, then, no more raw vegetables for me!" Every body is different and IBS is different in every person. Proponents of raw diets discuss the benefits of eating raw foods so as to benefit from the full array of enzymes in food and to reduce immune system reactivity during digestion. I would thus recommend that you be a scientist - do raw vegetables cause a problem for you? Is it just certain vegetables? You may find it helpful to use the FODMAPs list as a starting guide. Click here to learn about foods on the FODMAP diet.
If you would like to reap the benefits of raw vegetables, but are wary about the effects on your body, one option is to consider the use of juicing. Although I am only making an educated guess, juicing may provide a more comfortable way to access the nutritional benefits of raw vegetables:
Of course, there is always the option of just cooking them!