Healthy gourmet

Hippocrates, the father of medicine, is said to have first suggested the healing power of food, when in 431BC he said: "Let food be thy medicine and medicine be thy food." In the past decade, many studies have shown a relationship between what we eat and brain function.

Flavanols have been associated with a decreased risk of dementia, according to the American Heart Association. Research by the Alzheimer's Association in 2009 showed that eating a "heart healthy" diet and participation in moderate physical activity may help preserve our memory and thinking abilities as we age. It suggested that whole grains, vegetables, low-fat dairy foods and nuts may offer benefits for cognition in later life.

Food - or, more specifically, cooking - can help develop our imagination, which is constantly under threat of being repressed, by the "common sense" of the communities in which we live.

I spent an afternoon with chef Pietro Leemann at Ristorante Joia in Milan, Italy. He believes in the power of ideas: "Most chefs make dishes that are a combination of ingredients. But my food is the outcome of a creative artistic process."

As he speaks, Leemann places a dome-shaped crispy leaf of cabbage to conceal a vegetable terrine. He calls the dish "The Navel of the Planet".

The cabbage dome is a symbol for the world and the need for a green solution to protect it.

Joia was the first vegetarian restaurant in Europe to be awarded a Michelin star. The menu lists dishes such as Wild, Travel Notes, Serendipity in the Garden of My Dreams, and The Phoenix's Dream.