The National Diet and Nutrition Survey of Young People aged four to 18, published this summer by the Department of Health and the Food Standards Agency, found that British children are eating far too few vegetables and fruit, and too much salt, saturated fat and sugar, most of which comes from fizzy drinks, chocolate, and sweets. And another recent survey shows that each pupil spends roughly pound;6 a week on junk food (TES, September 15).
My daughter Isabella, 12, who attends a girls' grammar school in Kent, tells of overweight pupils staggering out of the tuck shop clutching handfuls - sometimes boxfuls - of fizzy drinks and confectionery. As far as she knows, there is no limit to the amount the girls are allowed to buy. The tuck shop does not stock any fruit, and the nearest thing to a healthy snack is a small packet of dried raisins.
"Junk food" is an emotive term. Sweets and chocolate provide instant gratification. An occasional packet of crisps makes a perfectly acceptable snack, while a chocolate-coated biscuit is often just what's needed to fill up the corners without permanently damaging teeth or health. It's regular bingeing on sugar which leaves kids physically and mentally starved. Confectionery without the balancing effects of fresh, whole fods impairs concentration and performance, and paves the way for obesity, poor teeth and serious health problems such as heart disease, cancer, high blood pressure and diabetes.
So how can parents keep tuck shop purchases under control? For a start, we can limit the amount of money children are allowed to spend. We can also monitor television viewing as long as witless adverts bully us into paying for high-sugar, high-fat snacks. We can explain this aggressive snack culture to our children, and teach them advanced food skills such as walking to the fruit bowl and consuming some of the contents.
We should provide healthy snacks for our children to take into school - fresh and dried fruit, vegetable sticks, low-salt corn chips, rice cakes, bread sticks, sunflower seeds (some modern research suggests these can help satisfy cravings for sugary and snacky foods) and more exotic snacks such as wholeflour chapatis.
The Guild of Food Writers believes that every school should set up a healthy food policy, and that school food should be covered by Ofsted. Parents should tackle school governors and press for a wider variety of foods to be sold at the tuck shop, including fruit.
But setting an example is best. Dr Andrew Hill, a psychologist at the University of Leeds, who specialises in children's diets, believes that children absorb their parents' attitudes to food. So long as healthy foods are available at home, children will return to them sooner or later.
Fiona Marshall lives in Broadstairs, Kent