Is this ALL the food you can eat, or just ALL the veggies and starch you can eat? By the way, I thought yams and sweet potatoes were the same thing!
I have a severe case of IBS, but I can eat many more veggies and starches than you list. Please read Heather's website front to back again! She gives great tips on how to prepare some of the trigger foods so that they are safer to eat. I've tried her tips and unbelievably I've been able to add gads of food (real variety!) to my diet!
My latest additions include organic tomatoes (peeled and most seeds removed) and organic mushrooms (peeled). One of the tricks is to not eat too much of the trigger foods. For example, I can tolerate a teaspoonful of organic brocolli every night for dinner without any trouble at all. But anything more than a teaspoonful would be too much.
Another trick is puree some of the trigger foods. For example, I just bought pureed corn in the babyfood section. I'm going to try a little for dinner one of these days.
The trick is also eating the trigger foods with lots of soluble fibre.
Does this help at all? If you have IBS, I highly recommend you stick with Heather's diet. I've had IBS all of my life (46 years) and I know from personal experience Heather's diet is 100 per cent correct.