According to the official food watchdog in Britain the Food Standards Agency (FSA), many Brits do not understand how to follow a balanced diet despite numerous campaigns highlighting which foods are healthy or unhealthy.

A survey conducted by the FSA shows that there is widespread ignorance about how much starchy food such as rice, bread and pasta should be eaten.

There is also considerable confusion over what can contribute towards the target "five a day" intake of fruit and vegetables.

The FSA believes conflicting messages from different weight-loss diets could be adding to the confusion and creating misconceptions.

The FSA survey of 2,094 people found that only 11% of people correctly said it was important to eat lots of starchy foods, only 45% realised tinned fruit and veg count towards "five a day"; 54% understood frozen fruit and veg can count and 53% realised dried fruit count.

Seventy three percent recognised the importance of eating lots of fresh fruit and vegetables but 19% wrongly thought eating plenty of fruit and veg could "outweigh" eating fatty, sugary foods and 58% realised foods high in fat and sugar should only be eaten occasionally.

Seventeen per cent believed they could limit the damage through exercise - even though burning off calories does not stop saturated fat in unhealthy foods potentially causing heart trouble.

As a result the FSA has re-designed the image it uses to show what makes up a healthy diet with a newly-designed "eatwell plate" which uses photos of different foods and renames some food groups.

Rosemary Hignett, head of nutrition at the FSA says consumers ought to know the proportions of each food group needed for a healthy balanced diet.

Hignett says the advice is not a '10-minute fad' but rather a diet for life which will help reduce the number of diet-related illnesses such as heart disease, stroke, diabetes and some cancers.

Potatoes do not count towards the target "five a day" portions of fruit and vegetables, says the FSA, but baked beans do.

According to the FSA a healthy, balanced diet should be made up of around one third fruit and vegetables, one third bread, rice, potatoes, pasta and other starchy foods, 15% milk and dairy foods, 12% meat, fish, eggs, beans and other non-dairy sources of protein and just 8% food and drink high in fat or sugar and no more than 6gms of salt a day.

The new image will be used by dieticians, nutritionists and the National Institute of Health and Clinical Excellence.