Families are feeling the financial pinch right now, and that includes in their weekly shop.

A study by the comparison website Mysupermarket.com found food prices are rising by about 14 per cent annually and families will spend £1,000 more on groceries this year than they did last year.

Unfortunately, it seems some people are turning to cheaper processed foods to save money. A survey by Christians Against Poverty found that nearly a third of adults were eating less healthily than they were a year ago.

But if families want to save money, the last thing they should do is opt for cheap junk food or processed snacks, says the Bristol-based food consultant and cookery teacher Francine Russell.

"People think buying processed and ready meals is cheaper," she says, "but there's nothing much in these foods except a lot of fat and sugar.

"If people went back to basics and cooked proper food they would end up with healthier diets – and it'd be cheaper, too.

"The credit crunch could be an opportunity – it could encourage us all to eat a healthier diet."

The last time British families were seriously restricted in the kitchen was after World War II when rationing was still in force. We were much healthier as a result – but we were also a very different nation back then. For a start, we knew how to cook.

Today, not only has at least one generation – if not two – grown up without learning basic cooking skills, we've also become accustomed to a more affluent world where buying ready meals and bags of washed salad is seen as standard.

Liz Fox, senior health promotion specialist at Bristol Primary Care Trust, says a big part of the problem is that cooking is no longer taught in schools. And because many of today's parents weren't taught cookery either they can't pass on those skills to their children.

"People are also very busy and they buy what they know," she says. "We've had someone chopping an onion with its skin on – it's that basic – and I think a lot of people are scared of trying new things."

In an attempt to address this lack of basic cookery skills, Liz, Francine and Bristol City Council launched the Cooking From Scratch project for teenagers and young parents two years ago.

The project was among a host of healthy eating initiatives which netted Bristol a National Food Champion 2008 award from the Food Standards Agency. The six-week classes have proved enormously successful, and they're now aimed at training key workers to teach others.

It's an approach adopted by celebrity chef Jamie Oliver in his latest Ministry of Food campaign. For his latest TV series, Jamie has been teaching recipes to groups of people so they can to pass on their skills to others. Jamie also wants the Government to set up "cookery hubs" around the country at which people can learn basic cooking skills.

His TV programme was criticised for featuring the worst cases, such as a woman who ate 10 packets of crisps for dinner and didn't know what boiling water looked like. But Francine says she is always amazed by at the lack of cookery skills she encounters among people from all backgrounds. And she says it's far easier – and quicker – to cook a simple meal than people think. "It really doesn't take very long to cook a soup or a casserole," she says, "and once it's in the oven you can get on with other jobs in the house."

Saving money is also about using up what we've bought. We're incredibly wasteful, throwing away 2.1 million tonnes of food to the tune of more than £5 billion every year in the UK, according to the Love Food Hate Waste campaign.

Simply using up our leftovers properly – in packed lunches, for example – could save as much as £100 to spend this Christmas.

Julia Falcon, from Love Food Hate Waste, says: "Most of the time there's a packed lunch waiting in the fridge if only we noticed it – so there really is such a thing as a 'free lunch'."