Dr. Mcdougall's elimination diet may help you get the IBS under control.
http://www.drmcdougall.com/med_allergic.htmlIn general, if you cannot identify a definite organic cause for your health problem, then suspect that it might be due to an allergy, especially to one caused by something you're eating. Then search for the culprit. A dietary approach to managing food allergies is the safest and most sensible step you can take for testing and for treatment. Take symptom-controlling drugs only as a last resort.
The next step in identifying a food that might be the cause of your allergy is to follow an elimination diet. This diet allows you to eat the foods that are least likely to cause your allergic reaction. When you begin this diet, allow about one week in order to completely clear the body of foods that were eaten before starting the diet. By the end of this week, if their trouble was indeed due to their foods, most people will be relieved of symptoms. During the elimination period, all foods should be thoroughly cooked, because cooking alters the proteins in them, making them less likely to provoke allergic responses.
Foods to eat on an elimination diet:
Starches (all cooked), including:
brown rice
sweet potatoes
winter squash
taro (or poi)
tapioca rice flour
puffed rice
Most Green, Yellow, or Orange Vegetables (all cooked), including:
beets
beet greens
chard
summer squash
artichokes
celery
string beans
asparagus
spinach
lettuce
Fruits (all cooked), Most non-citrus including:
peaches
cranberries
apricots
papaya
plums
prunes
cherries
Condiments:
Salt only is allowed (if not restricted for other health reasons). (This means no salad dressings, mustard, lemon juice, vinegar, as well as other condiments.)
Beverages:
water
After a week on this kind of fare, your food allergies should have ended and you should be feeling well. If this is the case, then you should begin to add other foods to the diet, but only one at a time, to determine if any of them causes your allergic reactions. For testing purposes, each "new" food should be eaten in large amounts three times a day for two days.
If the food does not cause a reaction, you can conclude that it is nonallergenic. Most reactions occur within a few hours, but some do not show up for several days. Each food must be tested individually; do not introduce two new foods at once. When you do have an allergic reaction to a specific food, you must wait four to seven days before testing the next item. This interval gives you the time you need to clear your system of that allergy-causing food.