I'm building up to my first 1/2 IM in April and need a bit of help around the food side of things. Here's my situation:

I have exercised recreationally for most of my life but recently stepped it up to some endurance events . I'm not out to win - I simply want to bush the comfort and challenge barrier. I'm out to try a number of different challenges so am not going to go to the expense of kitting out for each speciality. I still run in my boardies and ride my mountain bike in these kind of events.

I'm 35 years old, 1.8m tall, and weigh 78kg. I eat a good balanced diet and my weight is fairly stable. I often wonder what the difference would be if I could drop to about 75kg, but any time I try to reduce the food intake I just end up damn hungry and going back to normal patterns after a few days.

Here's what a typical day's food might look like:
Breakfast: 60g wheat cereal or oats with apple, yoghurt, and light sprinkle of raisins
Morning tea: 2 pieces wholegrain bread with avocado or peanut butter
Lunch: 2 sandwiches (4 pieces wholegrain bread) with salad and a little meat + 1 piece fruit
Afternoon tea: A handful of almonds, pretzels, crackers
Dinner: Pasta with roasted veges, maybe some meat
Late snack: fruit, or fruit toast

If I'm out for a long ride (e.g. 2 - 3 hours) or other exercise there will also be a banana and muesli bar.

That kind and quantity of food is fairly typical, but with lots of variety - it's not the same things day in and day out. I feel like it's a lot of food yet I'm still sometimes low on energy during training and often still feel hungry at various times during the day. The good news is all this exercise makes me want to eat the good food and avoid the junk!

So big question - does this much food seem appropriate for my situation? Any suggestions for changes?

Thanks!