I was flicking through a couple of cycling books last night and found conflicting advice about when to start eating for an event or long ride. One said you could start refuelling straight away, even have a snack a couple of minutes before the ride (but not earlier as you'd get an insulin reaction); the other advised not to eat anything for the first 45 minutes, but didn't give any back-up reasons. What do you guys think?

Also, if you're taking a mix of energy drink and cereal bars on a ride, which would it be better to consume first? I'm thinking that if I save the cereal bars for last, they might not even digest before the end of the ride - is that right?