In Britain, it’s the norm to have three square meals a day, and most of us look forward to eating them. One in four of us snack between our meals, and 10 per cent of people average three snacks a day.

Three years ago, I was that person eating six small meals a day and still feeling exhausted by 3 PM. Then a friend mentioned she was eating just once a day and had more energy than ever. I thought she ...