Walking past a primary school in my neighbourhood in Paris, I always look to see what pupils are getting for lunch.
On one day, before the end of last term, I noticed that they had tomato salad, chicken curry with pasta shells, creamy tomme blanche cheese and an apple compote. The weekly menus, displayed outside the school doors, are colour-coded to indicate nutritional value - orange for protein, green for fruit and vegetables, brown for starch, blue for dairy.
School dinners follow precise nutritional rules to ensure at least one balanced meal a day for France's children. A nation that prides itself on the quality of its food, it was one of the first European countries to establish a National Programme for Nutritional Health (PNNS).
For the past 20 years, the annual Semaine du gout - "Taste Week" - has taught the young about good eating, with chefs visiting schools or inviting pupils to restaurants, demonstrating skills and introducing children to new foods and flavours.
But despite schools' best efforts, obesity is rocketing - especially among children. And plump children become fat adults.
A survey of 25,000 over-18s, published in November, showed that there were 20 million overweight French adults, of whom 6.5 million were obese - three million more than 12 years ago. And they are getting fat younger.
Nearly one in five children is overweight or obese, and child obesity doubled in the previous decade, according to the 2006 PNNS study. For youngsters from disadvantaged families, the rate soars to 30 per cent.
The French are eating more, but less healthily, says AFPA, the Association Francaise de Pediatrie Ambulatoire. It blames "cars, lifts, television, computers and video games".
France's food safety agency found that just over six out of 10 boys, and fewer than one in four girls, took the recommended hour's daily exercise.
Now the buck has passed to the top. In October, President Sarkozy appointed a commission to investigate the prevention of obesity in all groups.
Perhaps a national regime of fresh tomato salad and chicken curry could help diminish the nation's waistlines.