There used to be a subject taught at school called home economics and it did exactly what it describes – taught pupils how to economically manage food. Gordon Brown's comment caused paroxysms of self-righteous indignation amongst many people (the truth hurts) but I've noticed signs that many, including a lot of younger people with sensible heads on them, are learning not to waste food, regarding it as unethical and wrong. It also costs money!

I couldn't help noticing that Lurpak butter had a high profile ad campaign encouraging people to use leftovers (with a dash of Lurpak, of course, but it was an encouraging sign). You can get two or three meals out of some things if you are a bit creative.

Reading Gerald Jarratt's letter on pigswill reminded me of my uncle. He had a smallholding near Ripon and every few weeks he would collect swill from school kitchens (Matthew Murray school and Leeds Girls High). He had to boil it for many hours, burning wood. Thinking back, I can see why it was banned. The natural food of pigs are acorns, not bits of pudding, pink custard and pieces of meat all floating around! If we're going to eat these animals, we have to remember that what we feed them affects the taste!

Today schools teach 'food technology' which includes projects like "design a pizza" (is it any wonder many kids think food doesn't go beyond pizza?). Also, learning about food hygiene is a good thing but there is an obsession with germs which has led to a lot of unnecessary waste – there is an inbuilt inflexibility in many food regulations.

At the end of the day, it is the food standards agency and supermarkets who are behind a lot of waste. The bright spark who came up with 'use by' and 'sell by' dates has a lot to answer for; he didn't think it through! Many foods are not appropriate for 'use by' dates, such as fruit and vegetables where you can tell by common sense if they are still edible. Tinned food has an almost indefinite 'use by' date.

Supermarkets should put sensible advice about 'use by' dates, making people realise they are guidelines only and won't turn to mould the day after the date! A little old fashioned common sense is all it takes, but it isn't too common these days!

JOHN ROBERTS, St Johns Court, St Johns, Wakefield.