The PKU diet has been a medical success story in that, through the work of dedicated, and in many cases absolutely selfless doctors and researchers, it has saved generations of PKU sufferers from acute mental and physical retardation. We are all fully aware that, if left untreated, PKU can have awful consequences. Early diagnosis via the heel prick test followed by a supervised prohibition of practically all normal foodstuffs and sustenance through artificial, laboratory-made supplements has, since the 1960s, saved people born with PKU from drastically reduced lives. We are all in agreement that everybody involved in the development of the diet deserves the heartfelt gratitude of PKU patients, parents and carers. However, things have changed since the arrival of a drug treatment. We consider it unacceptable for the NHS to insist on the diet as the sole treatment for PKU, when a drug has been developed which could lessen its harshness for a presently unknown proportion of the PKU community.
We also believe that descriptions of the diet as “highly effective” and suggestions that there is “no failure of dietary treatment itself” are not borne out by the experience of PKU sufferers and families. We believe the diet “fails”, inasmuch as it entails real unacknowledged costs to the patient and their families. For example, the parental and clinical indoctrination from birth necessary to prevent a child from engaging in an essential human activity – the daily enjoyment of choosing and consuming a wide range of food – produces a reduction in the quality of the patient’s life. PKU children have to be trained from a young age to try and ignore the constant media messages about food (how many celebrity chefs are there on TV, how many food commercials?) Learning about food is an important part of a growing child’s discovery of the world, which has to be made uniquely fraught for PKU children. We believe that the NHS, when reaching its decisions, should be made fully aware of the psychological pressures of living in a world in which practically all mundane, readily available food presents a constant danger to full mental and physical health. They should also be aware of the central role food plays in developing socialising and bonding skills socialising and bonding skills with all the associated life opportunities that these skills bring with them. We also know that the teenage years are when compliance with the diet may start to weaken as a result of the necessary relaxation of parental control. The parental control required to ensure compliance throughout adolescence itself presents a danger to personal and emotional development. The diet can fail in the teenage years because, as brilliant, committed and strong-willed as PKU teenagers are, and however effectively influenced in childhood they have been, they are only human.