London:  Keeping up with the Joneses used to mean owning a faster car or bigger house than your friends.

Now competitive middle-class mothers are engaged in a battle over the contents of their children's lunch boxes.

Parents are advised to feed their offspring aduki beans and "seaweed sachets". The trend is being encouraged by Mumsnet, a social networking website for mothers, and comes at a time of mounting concern over children's eating habits at school.

The site advises: "Don't forget that what you pack is open to scrutiny - not just by other children but by other mums. So if your child is going to a friend's house after school, make sure that's not the day you give in to Fruit Shoots and Gregg's sausage rolls.

"Stick a few stray aduki beans/ arugula [rocket] leaves/seaweed sachets in the lunch box. Your child might be a tad confused but your position as Alpha Mother will be assured."

Mumsnet's other recommendations include trying a themed lunch, such as falafel with hummus and pitta bread. Another suggestion is to involve children in preparing their lunch.

- Evening Standard