It's vital that children take healthy packed lunches to school. It is one of their main meals of the day and will affect how they behave, concentrate and learn in the afternoon. But what about grown-ups? Lunch is one of our three main meals too. The days of spending £5 on a sandwich, drink and packet of crisps now feels slightly profligate in these cash-strapped times. Instead, why not knock something up at home for half the price?

First think about what will be easy to make, transport and eat - and still be tasty, nutritious and not bore you to tears if you have it every day. The answer lies in planning. As with children's lunches, break yours down into the five basic essentials too.

Starch A starchy food will provide slow-release energy. Try pitta bread, tortilla wraps, granary or rye bread, or pasta.

Protein Protein will keep you full and maintain concentration. Choose from lean roasted meats, salmon, tuna or mackerel, hard-boiled eggs, peanut butter or pulses, including soups. Easy options include using up roast from a weekend joint, small cans of fish, or small pots of hoummos.

Dairy A dairy food gives you bone-strengthening calcium. You could pack a yoghurt or fromage frais (a calcium-fortified soya version if you are vegetarian), or a small cube of cheese (about 30g).

Fruit and veg Include a couple of servings. This could be a tomato in your sandwich, pepper or carrot crudités, button mushrooms, plus an apple, banana, pear or pot of ready-prepared fresh fruit salad. Small cans or plastic pots of fruit also count.

Drink Don't spend a fortune on smoothies and juices. Stick to water.

Pluck out your favourites and either have similar things each day, such as a pitta, so that you use the whole pack, or freeze a bag of pittas and tortillas. Get one out each night before you go to bed and mix and match over the next few weeks.

It takes a couple of weeks to get into the swing of things, but the more you think and plan and shop, the easier and more interesting the whole process will become. Just remember that your packed lunch is not some kind of inferior stop-gap but a proper main meal that will affect your long-term weight and health from the inside out.

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