The reductionist scientific model of food is that it is merely a complex mixture of nutrients that should be combined in optimal proportions to meet both current needs and to maximise health and longevity in the longer term. Nutritionists classify foods according to the nutrients that they contain and these classifications are used to advise and guide consumers towards a healthy diet. Foods were initially classified into food groups according to their nutrient profiles and consumers advised to eat specified minimum amounts from each food group to ensure that their diet had adequate quantities of all the essential nutrients. Consumers also classify foods but such classification systems have not traditionally had any theoretical basis in scientific nutrition. The traditional main course of a British dinner consists of a meat or other “protein food”, potatoes and one or more extra vegetables with sauce or gravy.