“School lunches with menus that are created by nutritionists are provided to all primary schools and the majority of junior high schools throughout Japan,” Mitsuhiko Hara, a pediatrician and professor at Tokyo Kasei Gakuin University, told AFP.

The lunches are mandatory — no packed lunches allowed — and while they are not free for most, they are heavily subsidised.

Each meal is designed to have around 600-700 calories balanced between carbohydrates, meat or fish and vegetables.

One sample meal served to children in Japan’s Gunma gives a flavour: rice with grilled fish and a spinach and sprout dish, served with miso soup with pork, alongside milk and dry prunes.

“School lunch is designed to provide nutrition that tends to be lacking in meals at home,” education ministry official Mayumi Ueda told AFP.

“I think it contributes to the nutritional balance necessary for children.”