Hi George,if you eat a sensible low fat diet you should be ok.I was worried about the side effects too specially since I have IBS but I only had one bad day really and that was cos I had a takeaway.
Just be careful to follow the guide lines and eat sensible meals and you'll be fine.Theres more you can eat than you first think,I'm never hungry now and rarely snack.To get really bad side effects you'd need to eat really the wrong food like lots of cheese or greasy fry ups.Give it a go at a weekend and see how you go.
I can only say what franky said, stick to the rule of 5g fat per 100g and you will be fine, and will have no side effects!! I also suffer with IBS and i have been fine unless i have eaten something i shouldnt of!!