IBS Diet

While there is no one diet or single food that can resolve or cause all the problems and symptoms of IBS, there are groups of foods that often act as GI stimulants or irritants.  These often include foods high in fat, insoluble fiber, caffeine, coffee (even decaf), carbonation or alcohol.  They can trigger violent reactions of your gastrocolic reflex which causes spasms of the colon and can cause pain, diarrhea, constipation, gas and bloating.

General IBS Diet Rules:
1. Soluble fiber foods are safe and healthy for your bowel (see below).
2. Minimize fat intake to 25% or less of your diet.
3. Avoid high fat foods especially on an empty stomach.
4. Avoid insoluble fiber foods on an empty stomach (see below).
5. Eat slowly!
6. You control your diet and what you put in your mouth.  Think about what you are ingesting, and whether it is good for you at that point in time.
7. Avoid foods that can sometimes trigger IBS attacks like dairy, fried foods, coffee, red meat, soda, alcohol.
8. Consider soy or rice replacements for dairy, egg whites instead of whole eggs, avoid skin on chicken.
9. Use peppermint tea liberally, as needed for quick relief of symptoms of gas, bloating, belching, cramping.

Insoluble Fiber Foods: can be GI stimulants so avoid them when your bowel is acting up even though they are all considered healthy foods.

Apples  CherriesOnions/scallions
Apricots*CornPeaches*
Beans/LentilsCucumber  Pears*
Bell PeppersDatesPineapple
Bok ChoyEggplantPopcorn
BranGarlicRaisins
BroccoliGranolaRaw Fruit
Brussels SproutsGrapefruitRaw Vegetables
CabbageGreensRhubarb
CauliflowerLeeksSprouts
CerealLegumesTomatoes
CeleryNutsWhole Grains
  Whole Wheat Breads

* with skin

Soluble Fiber Foods: easier to digest

ApplesauceMushrooms
AvocadosOatmeal
BananasPapayas
BarleyPasta/noodles
BeetsPotatoes
Breads: Rice
    WhiteRice Cereals
    Fresh bakedSoy
    FrenchSquash
    Sour DoughSweet Potatoes
CarrotsTortillas
Corn mealTurnips
MangoesYams

Foods to Avoid:
Alcohol
Caffeine (coffee, sodas with caffeine)
Fatty Foods, i.e. ice cream
Fried Foods
Gassy Foods: beans, cabbage, bok choy, cauliflower, broccoli, asparagus, brussels sprouts
Large amounts of fructose in honey, apple, grape juice

Final Tips:

Keep a food diary if you think a certain food is causing your symptoms of cramping, gas or bloating.  If symptoms always occur after ingesting one item, then it is likely to be a gastro colic stimulant for you, and you should avoid it until your symptoms resolve. 
By keeping a diary you can identify a specific food, as opposed to a class of food that is a trigger to your gastro colic reflex.  Always remember that stress, and chronically stressful situations are some of the most common triggers for exacerbating your IBS symptoms.  Walk, bicycle, swim, do yoga, mediate or just take some time for yourself.  Sometimes that will be all that is needed to improve your symptoms.