An investigation into diet treatment for adults with previously untreated phenylketonuria and severe intellectual disability

There is evidence in the literature which suggests that adults with previou sly untreated phenylketonuria (PKU) benefit from a low phenylalanine diet A prospective study providing a phenylalanine-restricted diet to five subjec ts with severe intellectual disability arising from untreated PKU is report ed. Physical, social and behavioural measures were used to monitor the effe cts of the diet. Four out of the five subjects derived considerable benefit . It is concluded that the restricted diet is worth trying in most individu als with previously untreated PKU, and that possible benefits are in the ar eas of concentration, alertness, mood, irritability and adaptive behaviour.