General kitchen advice
Buy Local Food : ...but at the same time, figure out what makes sense. It is more energy efficient to raise lambs in New Zealand and ship them to the UK than to raise them in the UK, because New Zealand lamb farming is more energy efficient. It is also more energy efficient to buy produce raised in Spain, than produce that has to be grown in greenhouses in the UK. Baby steps require figuring out which things make sense and which don't.
Making your own lunch instead of buying from a sandwich shop saves on packaging, and could also save you approx £4 a day or £1,000 per year!
Diet types
The Glycaemic Index Diet
The gi (or glycaemic index) diet is reliant on the glycaemic index, a chart showing types of food and a score representing the ease that the glucose in the food gets converted to glucose in the dieters blood stream. The claim is that slow release types of food (ie with a low Glycaemic score), will keep you feeling full for longer and help you to consume fewer food without craving snacks all the time.
It is also extremely efficient for individuals with diabetes, as the low GI foods are helpful in controlling surges in blood sugar secretion.