How did it all begin? It was one of those things that crept up on us and we still can’t quite believe it happened. Looking back, we’d been in denial for some time. Then a friend who hadn’t seen the family for a while came round and blurted out the bald truth. ‘God, Dodi’s got rather fat. In fact, you know, I think that might count as obese.’ Once said, it had to be admitted. If you looked at Dodi from behind when he was sitting down, you could see a substantial spare tyre around his thirteen-year-old middle. It bulged out from his hips and flopped down like a muffin rising up and out over its baking case. He had become quite lazy too, preferring to lounge in front of the fire rather than play in the garden as he used to. His excess weight was slowing him down. He had been hooked on a particular brand of instant meal for ages. Guaranteed real tuna, the packaging said. Enriched with omega-3 and -6 fats! The small print told another story. What was inside was largely byproducts from other industrial processing: rendered poultry meal mixed with fillers of corn gluten meal,…