"Most Hongkongers don't understand what is in the processed foods they eat," says Alvina Chan, a renowned chef and graduate of Le Cordon Bleu Paris. "Potato flakes are, in fact, unwanted scraps of the root vegetable. They are deep-fried in fat and smothered in salt, flavour enhancers and preservatives. They are proven to be bad for our health and can lead to weight gain."
One in five Hong Kong teenagers is overweight, say health officials. A fast-food culture and sedate lifestyle have made things worse; youngsters tend to be tied up by private tutoring and video games rather than sports and outdoor activities.
That's why the charity Go.Asia teamed up with Chan to bring Jamie Oliver's Food Revolution to Hong Kong. Since 2010, the British chef and food advocate has been urging teenagers to forget fast food and rediscover the joy and benefits of cooking. His television series in the US has won an Emmy Award.
"You don't know what restaurants use to make your meals, but if you cook at home, you know you have control," Chan says. "We should always go for fresh and organic ingredients. Besides, cooking is a survival skill that'll be useful always. Your parents or helper won't be there to cook if you study abroad or move out."
The local revolution kicked off at International Christian School, in Sha Tin, last month, with cooking demonstrations that looked at just how bad processed foods are.
What's the difference, for example, between fresh orange juice and orange soda? Students cut up oranges and extracted the juice using a blender. Others mixed fizzy water, colourings, flavourings, sugar and preservatives the way soft drinks makers do.
"Orange sodas might not contain a drop of juice," Chan says. "Their flavour and colour comes from chemicals. They can last longer than fresh juice because of preservatives. It is no good for your health."
She says we should drink more juice and water. And rather than visiting fast-food chains, we should eat a healthy diet rich in five grains, organic fruits and veggies and omega-3 oils.
"Five grains are good for you: they're high in fibre, vitamins and minerals and can reduce the risk of heart disease, type II diabetes and certain cancers," Chan says.
She showed students how to prepare a lunch of salmon with tomato salsa and brown rice that fits this food philosophy.
The philosophy includes the idea of protecting the planet. "Nothing goes to waste," she says. Water used to wash the rice can be used to water plants, scattering lemon peel in a fridge can eliminate bad smells and avocado stones can be used to massage the shoulders.