When does overweight become obesity? The commonly used definitions are either that you are more than 20 % over your ideal weight, or if you have a BMI (Body Mass Index) above 30. Obesity is a growing problem worldwide, and the causes are clear - poor diet, particularly the consumption of junk food, and a sedentary lifestyle.

Fortunately the cure is as clear-cut as the causes - a healthy diet, containing a good mix of lean meats and fish, fresh fruit and veg, and whole grain carbs, combined with regular vigorous exercise.