Students at Red Maids School enlisted the help of their catering manager to create a tasty, frugal feast for five.

John Dier helped the girls make a two-course dinner of butternut squash soup and baked fish with rice and vegetables, with a smoothie, for under £6. Here he gives his tips for an economical but healthy diet.

John said: "Although diet fads come and go, there are some fundamental rules you can follow that won't cost any more and will help you to live a long and healthy life."

Look for food that is fresh and natural

Vary your diet – it is more likely to be balanced and enjoyable

Only eat free range meats and eat meat in moderation

Eat plenty of fibre

Lots of water to stave off headaches and fatigue

Minimize intake of salt, sugar and saturated fat

Don't eat... dine – sit down and enjoy your meal

Avoid overeating – stop just before you are full

Listen to your body