Sugar tastes good. It’s cheap, sweet and, like many drugs, is highly addictive. I have a close friend who was sent to rehab for drug abuse a decade ago. He is proudly clean and sober and consumes around five litres of cola a day. It makes him feel good and gives him a buzz of energy. His intake is extreme and there's no real indication of whether this addiction is any better or worse than the one he was originally treated for. The difference is, one of them is illegal, the other can be bought by six-year-olds at the corner shop.